Film Making] - Cinematography - Kodak Student Filmmaker's Handbook

WEDNESDAY, JULY 31

Student Filmmaker's Handbook

The Kodak Worldwide Student Program gratefully acknowledges the contributions of Ryerson Polytechnic University's Digital Media Projects Office in association with The Kodak Worldwide Student Program for the publication of The Student Filmmaker's Handbook.

l Introduction l Which Film Should I Use? l Anatomy of a Data Sheet l Sensitometric and Image-Structure Data l Physical Characteristics l Storage of Raw and Exposed Film l How do I know I'm ordering the right film? How to identify the

film's format, emulsion, length, and winding l Cores and Spools l Winding l Perforations l Film Identification l Filtration l Motion Picture Sound Recording l Projection l Dealing with a Motion Picture Laboratory l Laboratory Operations l Marketing a Film l Distribution and Promotion l Glossary of Motion Picture Terms

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Page 1 of 1KODAK: Student Filmmaker's Handbook

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andrés

WEDNESDAY, JULY 31

To The Student Filmmaker

The Student Filmaker's Handbook is a compilation of information available in many different Kodak publications. It is a resource for you to use as you pursue a career in this most exciting of industries.

It will interest you to know that you are entering the film industry at one of its most exciting and dynamic times. Technological innovations recently announced and those just around the corner guarantee that FILM will be a fascinating career far into the next century. Silver halide technology, the bedrock of film manufacturing, is moving ahead each year with new Kodak T-GRAIN® Emulsions and new and improved color dye systems. Our scientists assure us that they will be able to improve the quality of film many times over in the next few years. What that means for you is that you will be recording sharper and more accurate color images than you have ever seen before.

Those images will be manipulated in many new ways. HDTV (High Definition Television) is on the horizon and just beyond that is the whole new world of digital transmission of images over optical fiber networks. Eastman Kodak Company has recently demonstrated a new CCD HDTV-Telecine and a High Resolution Electronic Intermediate System which will bridge the gap between electronic and silver halide technologies. And that is just the beginning. The good news for you is that your productions on film will be recorded on the one worldwide production standard.

Wherever your work takes you, film will be the standard for motion- picture image production. And what's more, you will have recorded your program on the highest resolution, brightest and most accurate color medium in the world. No other technology offers the quality of a film image; and remember, that quality is going to improve in the years ahead.

So, welcome to the motion picture industry. I hope you will find this book useful, and I hope you will look upon Eastman Kodak Company as a source of quality products and technical support now and in the future.



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Which Film Should I Use?

Before selecting a specific film or films, you, the producer, and the director, will have to answer a number of basic technical and aesthetic questions about the entire production. The answers you provide will help greatly in the selection of the films that will best translate your concepts into moving pictures on a screen that convey your intended message accurately, completely, and effectively.

You should consider the following factors because they directly affect your choice:

l Anticipated release format. Will the finished prints be 35 mm or 16 mm? Shooting a 16 mm camera film to produce 35 mm release prints will involve some sacrifice in image quality.

l Number of finished prints needed. If you need only one and you need it fast, a reversal film designed for direct projection will be ideal. If you are producing several prints, the camera film should be selected with an eye toward the economics of the various film printing systems.

l The finished form of the picture. Should the finished film be in color or in black-and-white? The aesthetic impact of black-and-white film is distinctly different from that of color. What feeling should the film convey? The sharp distinctions in hue and density provided by a color film image can convey more information than the same image composed of shades of gray. Filmmakers should not assume, however, that color is always more interesting, or that black and white is always less expensive. Should the film be silent or should it have sound? A sound track can help to focus and direct a viewer's attention to the message. Answers to these questions depend on the purpose and audience for the film.

l Type of lighting and exposure index. Will the subject be filmed indoors or out? Can you control the light? Some films are especially designed for low levels of light or for sensitivity at particular bands of the spectrum. All films are balanced for particular kinds of lighting. Will your film give you an accurate record of the colors in the scene if you make the motion picture only in the light available to you?

l Type of filtration needed. If you have to use several filters to compensate for uncontrolled elements in the scene or in the lighting, will the film be fast (sensitive) enough to record a high-quality image?

l Type of processing and printing facilities available. Few labs process all types of film. If your nearby laboratory processes only color film, you may have to send your black-and-white film to an out-of-town lab. This situation can be especially time-consuming if the film requires editing and must be shuttled back and forth several times. You can avoid much anxiety by getting to know the personnel at the laboratories that process your films and explaining your special needs to them. It may be worthwhile to select films that can be processed by a laboratory directly familiar with your needs.


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Anatomy of a Data Sheet

l Film Types, Names, and Numbers l Film Descriptions l Negative Camera Films l Exposure Information

¡ Exposure Index ¡ Exposure Latitude ¡ Illumination (Incident Light) Table ¡ Lighting Contrast Ratios ¡ Reciprocity Characteristics ¡ Filter Factors ¡ Color Balance ¡ Printing Conditions

Kodak's film data sheets are the best source for technical information about Kodak and Eastman Motion Picture Films. Each data sheet consists of one or more pages of detailed technical information for a particular film. These sheets provide useful information for the careful and knowledgeable reader.

In the discussion of professional motion picture films that follows, we are using that form of a Film Data Sheet as a road map. The next four pages illustrate a data sheet for a hypothetical film that can be used in every stage of motion picture work. A real data sheet would obviously have fewer entries--camera film data sheet, for example, does not contain paragraphs titled "Printing Conditions" because printing conditions are only relevant to laboratory and print films.

The large circles on the hypothetical data sheet illustration that is shown on the next few pages contain page numbers referring you to the beginning of a discussion on that specific topic. For example, the data sheet has a (4) on the section "exposure indexes." If you scroll down and find the (4) and the heading "Exposure Index," you can read about that topic. Each number on the data sheet will refer you to that section in the text.

A single free copy of any film data sheet is available from our website or write: Eastman Kodak Company, Dept. 412-L, Rochester, NY 14650-0532.



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Film Types, Names, and Numbers areas 1 and 2

Film production-from recording motion with a camera to projecting the image on a screen or cathode-ray tube-often involves three different kinds of film.

Camera film is used to record the original scene. Many kinds of camera films are available for the many conditions under which subjects often must be filmed, for the special effects the cinematographer wants to produce, and for the processing and projection requirements of the job.

Once the film has been edited from a workprint, laboratory films used to produce the intermediate stages needed in the lab for special effects, titling, etc. Using intermediates also protects your valuable, original footage from potential damage during the printing process.

Print film , on the other hand, is used to print both the first workprint and as many copies as needed of the final edited version of the project.

People in the photographic industry generally refer to films by number (5248, for example) rather than by name (Eastman Color Negative II Film, in this case). Thus, the four -digit number is more prominently displayed on the film data sheet than the name. The first of the four digits indicates the size or "gauge" of the film. When the first digit is 5, the film is 35 mm or wider; a 7, on the other hand, indicates a 16 mm film or a film that will be slit down to these narrower gauges after processing. When a film is available in both the 16 mm and 35 mm widths, both the 7000 and 5000 series of digits appear on the data sheet.

The name also indicates properties of the film. Kodak EKTACHROME Film indicates a reversal color film. Panchromatic and orthochromatic refer to the light-sensitivity range of the film. Most film names are self- descriptive.

The important thing to remember about the name and number is to use both accurately when ordering film or film data sheets.

Film Descriptions area 3

Under the heading General Properties on a typical data sheet, there will always be a brief description of the overall characteristics of the film. The paragraphs that follow describe each of the Kodak and Eastman Motion Picture Films currently available and are similar in coverage to paragraphs found on each film data sheet.

Negative Camera Films

Camera films are available in two general types: negative and reversal. Negative film produces an image that must be printed on another stock for final viewing. Since at least one intermediate stage is usually produced to protect the original footage, negative camera film is an


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efficient choice when significant editing and special effects are planned. Printing techniques for negative-positive film systems are very sophisticated and highly flexible; hence, negative film is especially appropriate for complex special effects. All negative films can go through several print generations without pronounced contrast buildup.


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WEDNESDAY, JULY 31



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Exposure Information

Film data sheets for camera films give exposure information under these headings: Film Exposure Indexes, Illumination Table, Lighting Contrast Ratios, Reciprocity Characteristics, and Filter Factors (black-and-white film) or Color Balance (color films). Explanations of each of these elements are explained on the following few pages.

Exposure Index area 4

The film Exposure Index (EI) is a measurement of film speed that can be used with an exposure meter to determine the aperture needed for specific lighting condifions. The indexes reported on film data sheets for Eastman and Kodak Motion Picture Films are based on practical picture tests but make allowance for some normal variations in equipment and film that will be used for the production. There are many variables for a single exposure. Individual cameras, lights, and meters are all different (lenses are often calibrated in T-stops). Coatings on lenses affect the amount of light that strikes the emulsion. The actual shutter speeds and f-numbers of a camera and those marked on it sometimes differ. Particular film emulsions have unique properties. Camera techniques can also affect exposure. All of these variables can combine to make a real difference between the recommended exposure and the optimum exposure for specific conditions and equipment. Therefore, you should test several combinations of camera, film, and equipment to find the exposures that produce the best results. Data sheet Exposure Index figures are applicable to meters marked for ISO speeds and are used as a starting point for an exposure series.

When it comes to measuring light, there are three kinds of exposure meters: The averaging reflection meter and the reflection spot meter are most useful for daylight exposures while the incident exposure meter is designed for indoor work with incandescent illuminations. Detailed directions for using all three are given in Kodak Pocket Photoguide, Kodak Publication No. AR-21). The two reflection meters are sometimes used with the Kodak Gray Card. One side of the card has a neutral 18-percent reflection which can be used indoors to aid in measuring the average reflection for a typical subject. You can also use this side of the card outdoors by increasing the exposure 1/2 stop above the calculated exposure. The other side of the card has 90-percent reflection for use at low- light levels. The use of this card and appropriate adjustments for aperture and exposure time is covered in Kodak Gray Cards, Kodak Publication No. R -27.

Exposure Latitude

Exposure latitude is the range between overexposure and underexposure within which a film will still produce usable images. As the luminance ratio (the range from black to white) decreases, the exposure latitude increases. For example, on overcast days the range from darkest to lightest narrows, increases the apparent exposure latitude. On the other hand, the exposure latitude decreases when the film is recording subjects with high-luminance ratios such as black trees against a sunlit, snowy field.


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Illumination (Incident Light) Table area 5

When the illumination is very low or when you cannot make reflected-light measurements conveniently, use an incident-light meter can be used to read the illumination direcdy in footcandies (lux).

Note: Lux is the term used to describe the intensity of the exposing light in the current international standards for determining film speed. Most existing incident-light meter scales are still marked in footcandles. A footcandle is approximately equal to 1/10 metre -candle or lux.

Lighting Contrast Ratios area 6

When using artificial light sources to illuminate a subject, you can determine a ratio between the relative intensity of the key light and the fill lights. First, measure the intensity of light at the subject under both the key and fill lighting. Then measure the intensity of the fill light alone. The ratio of the intensities of the combined key light and fill lights to the fill light alone, measured at the subjects, is known as the lighting ratio.

Except for dramatic or special effects, the generally accepted ratio for color photography is 2 to I or 3 to 1. If duplicate prints of the camera film are needed, the ratio should seldom exceed 3 to 1. For example, if the combined main light and fill light on a scene produce a meter reading of 6000 footcandles at the highlight areas and 1000 footcandles in the shadow areas, the ratio is 6 to 1. The shadow areas should be illuminated to give a reading of at least 2000 and preferably 3000 footcandles to bring the lighting ratio within the permissible range.

Reciprocity Characteristics area 7

Reciprocity refers to the relationship between light intensity (illuminance) and exposure time with respect to the total amount of exposure received by the film. According to "The Reciprocity Law," the amount of exposure (H) received by the film equals the illuminance (E) of the light striking the film multiplied by the exposure time (t). In practice, any film has its maximum sensitivity at a particular exposure (i.e., normal exposure at the film's rated exposure index). This sensitivity varies with the exposure time and illumination level. This variation is called "reciprocity effect." Within a reasonable range of illumination levels and exposure times, the

Lighting contrast ratio 2:1 Lighting contrast ratio 5:1

Figure 1



film produces a good image. At extreme illumination levels or exposure times, the effective sensitivity of the film is lowered, so that predicted increases in exposure time to compensate for low illumination or increases in illumination to compensate for short exposure time fail to produce adequate exposure. This condition is called "Reciprocity Law Failure" because the Reciprocity Law fails to describe the film sensitivity at very fast and very slow exposures. The Reciprocity Law usually applies quite well for exposure times of 1/5 second to 1/000 second for black-and-white films. Above and below these speeds, black-and-white films are subject to reciprocity failure but their wide exposure latitude usually compensates for the effective loss of film speed. When the law does not hold, the symptoms are underexposure and change in contrast. For color films, the photographer must compensate for both film speed and color balance changes because the speed change may be different for each of the three emulsion layers. However, contrast changes cannot be compensated for or contrast mismatch can occur.

Filter Factors area 8

Since a filter absorbs part of the light that would otherwise fall on the film, you must increase the exposure when you use a filter. The filter factor is the multiple by which an exposure is increased for a specific filter with a particular film. This factor depends principally upon the absorption characteristics of the filter, the spectral sensitivity of the film emulsion, and the spectral composition of the light falling on the subject.

Published filter factors apply strictly to the specific lighting conditions under which the measurements were made, so it may be desirable, especially for scientific and technical applications using reversal films, to determine the appropriate filter factor under actual working conditions.

To determine a filter factor, place a subject with a neutral-gray area, a Kodak Gray Card, or a photographic gray scale in the scene to be photographed. Shoot the scene without filtration. Then, with the filter or filter pack in place, shoot a series of exposures at 1/2-stop intervals ranging from 2 stops under to 2 stops over the exposure determined using the published filter factor. Compare the (neutral-gray) density of one frame in the unfiltered scene with the density of one frame in each one of the filter series, either visually or with a densitometer to find the filtered exposure that equals the unfiltered exposure in overall density. The filter factor is the ratio of the filtered exposure to the unfiltered exposure with equal densities.

Conversion of Filter Factors to Exposure Increase in Stops

Filter Factor

+ Stops

Filter Factor

+ Stops

Filter Factor

+ Stops

1.25 +1/3 4 +2 12 +3 2/3

1.5 + 2/3 5 +2 1/3 40 +5 1/3

2 +1 6 +2 2/3 100 +6 2/3

2.5 +1 1/3 8 +3 1000 +10

3 +1 2/3 10 +3 1/3 - -

Filter Factor = Exposure with filter

Exposure eithout filter



Color Balance area 9

Color balance relates to the color of a light source that a color film is designed to record without additional filtration. All laboratory and print films are balanced for the tungsten light sources used in printers, while camera films are nominally balanced for 5500 K daylight, 3200 K tungsten, or 3400 K tungsten exposure.

When filming under light sources different from those recommended, filtration over the carnera lens or over the light source is required. Camera film data sheets contain starting-point filter recommendations for the most common lighting sources: daylight, 3200 K tungsten, 3400 K tungsten, cool-white fluorescent, deluxe cool-white fluorescent, and Mole-Richardson HI Arc lamps (both white-flame and yellow-flame carbons).

Printing Conditions area 10

A representative printer setup is described for each laboratory or print film. These printer setups should be read for comparison purposes and used only as a starting point. The use of the Laboratory Aim Density (LAD) control method is recommended for determining optimum printing exposure.




WEDNESDAY, JULY 31

Sensitometric and Image-Structure Data

l Understanding Sensitometric Information l Characteristic Curves

¡ General Curve Regions ¡ Curve Values ¡ Color Sensitivity and Spectral Sensitivity ¡ Spectral-Dye-Density Curves

l Image Structure ¡ Modulation-Transfer Curve

l Graininess and Granularity ¡ Measuring RMS Granularity ¡ Factors That Affect Graininess ¡ Granularity and Color Materials ¡ Some Practical Effects of Graininess and Granularity

l Resolving Power

Sensitometry is the science of measuring the response of photographic emulsions to light. "Image-structure" refers to the properties that determine how well the film can faithfully record detail. The appearance and utility of a photographic record are closely associated with the sensitometric and image-structure characteristics of the film used to make that record. The ways in which a film is exposed, processed, and viewed affect the degree to which the film's sensitometric and image-structure potential is realized. The age of unexposed film and the conditions under which it was stored also affect the sensitivity of the emulsion. Indeed, measurements of film characteristics made by particular processors using particular equipment and those reported on data sheets may differ slightly. Still, the information on the data sheet provides a useful basis for comparing films. When cinematographers need a high degree of control over the outcome, they should have the laboratory test the film they have chosen under conditions that match as nearly as possible those expected in practice.



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Understanding Sensitometric Information

Transmission density (D) is a rneasure of the light-controlling power of the silver or dye deposit in a film emulsion. In color films, the density of she cyan dye represents its controlling power to red light, that of magenta dye to green light, and that of yellow dye to blue light. Transmission density may be mathematically defined as the common logarithm (Log base 10) of the ratio of the light incident on processed film (Po) to the light transmitted by the film (Pt).

The measured value of the density depends on the spectral distribution of the exposing light, the spectral absorption of the film image, and the special sensitivity of the receptor. When the spectral sensitivity of the receptor approximates that of the human eye, the density is called visual density. When it approximates that of a duplicating or print stock, the condition is called printing density.

For practical purposes, transmission density is measured in two ways:

l Totally diffuse density ( Figure 2) is determined by comparing all of the transmitted light with the incident light perpendicular to the film plane ("normal": incidence). The receptor is placed so that all of the transmitted light is collected and evaluated equally. This setup is analogous to the contact printer except that the receptor in the printer is film.

l Specular density ( Figure 3) is determined by comparing only the transmitted light that is perpendicular ("normal") to the film plane with the "normal" incident light, analogous to optical printing or

D = log 10 Po

Pt

Figure 2

Figure 3


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projection.

To simulate actual conditions of film use, totally diffuse density readings are routinely used when motion-picture films are to be contact printed onto positive print stock. Specular density readings are appropriate when a film is to be optically printed or directly projected. However, totally diffuse density measurements are accepted in the trade for routine control in both contact and optical printing of color films. Totally diffuse density and specular density are almost equivalent for color films because the scattering effect of the dyes is slight, unlike the effect of silver in black-and-white emulsions.


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Characteristic Curves area 11

A characteristic curve is a graph of the relationship between the amount of exposure given a film and its corresponding density after processing. The density values that produce the curve are measured on a film test strip that is exposed in a sensitometer under carefully controlled conditions and processed under equally controlled conditions. When a particular application requires precise information about the reactions of an emulsion to unusual light-filming action in a parking lot illuminated by sodium vapor lights, for example, you can filter the exposing light in the sensitometer can be filtered to simulate that to which the film will actually be exposed. A specially constructed step tablet, consisting of a strip of film or glass containing a graduated series of neutral densities differing by a conslant factor, is placed on the surface of the test strip to control the amount of exposure, the exposure time being held constant. The resulting range of densities in the test strip simulates most picture-taking situations, in which an object modulates the light over a wide range of illuminance, causing a range of exposures (different densities) on the film.

After processing, the graduated densities on die processed test strip are measured with a densitometer. The amount of exposure (measured in lux 1) received by each step on the test strip is multiplied by the exposure time (measured in seconds) to produce exposure values in units of lux-seconds. T'he logarithms (base 10) of the exposure values (log H) are plotted on the horizontal scale of the graph and the corresponding densities are plotted on the vertical scale to produce the characteristic curve. This curve is also known as the sensitometric curve, the D Log H (or E) curve, or the H&D (Hurter and Driffield) curve 2.

In the following table, the lux-sec values are shown below the log exposure values. The equivalent transmittance and opacity values are shown to the left of the density values.

Typical Characteristic Curve

The characteristic curve for a test film exposed and processed as described in the table is an absolute or real characteristic curve of a particular film processed in a particular manner.

Sometimes it is necessary to establish that the values produced by one densitometer are comparable to those produced by another one. Status densitometry is used for this. Status densitometry refers to measurements


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made on a densitometer that conforms to a specified unfiltered spectral response (Dawson and Voglesong, Response Functions for Color Densitometry, PS&E Journal, Volume 17, No. 5 Sept/Oct 1973). When a set of carefully matched filters is used with such a densitometer, the term Status A densitometry is used. The densities of color positive materials (reversal, duplicating, and print) are measured by Status A densitometry. When a different set of carefully matched filters is incorporated in the densitometer, the term Status M densitometry is used. The densities of color preprint films (color negative, intemegative, intermediate, low-contrast reversal original, and reversal intermediate) are measured by Status M densitometry. (DAK Densitometer Filter Sets are purchased directly from the manufacturers of densitometers. For further information, contact the densitometer manufacturer.)

Representative characteristic curves are those that are typical of a product

Figure 4

These illustrations show the relationship between subject luminance, negative density, and the characteristic curve. There is one stop difference in luminance between each of the points 2 to 10. Point 1 is a specular highlight which photographs as if it were about 2 stops brighter than point 2, which is a diffuse highlight. Point 9 is the tone to be reproduced just lighter than black. There are 7 stops difference between points 2 and 9, which is the typical range for normal luminance range subjects. Point 10 is about one stop darker than point 9, and reproduces as black. The graph shows where points of these brightness differences generally fall on a characteristic curve. Point 9 is exposed on the speed point of the film, which develops to a density of about 0.10 above the base plus fog density (the density of the clear film base after developing). The density range from point 9 to point 2 is about 1.05.



and are made by averaging the results from a number of tests made on a number of production batches of film. The curves shown in the data sheets are representative curves.

Relative characteristic curves are formed by plotting the densities of the test film against the densities of a specific uncalibrated sensitometric-step scale used to produce the test film. These are commonly used in laboratories as process control tools.

Black-and-white films usually have one characteristic curve (see Figures 5 and 6). A color film, on the other hand, has three characteristic curves, one each for the red-modulating (cyan-colored) dye layer, the green- modulating (magenta-colored ) dye layer, and the blue-modulating (yellow- colored) dye layer (see Figures 7 and 8). Because reversal films yield a positive image after processing, their characteristic curves are inverse to those of negative films (compare Figures 5 and 6).

Typical Characteristic Curves

Black and White Negative Film Black and White Reversal Film

Figure 5

Figure 6

Color Negative Film Color Reversal Film

Figure 7 Figure 8



WEDNESDAY, JULY 31

General Curve Regions

Regardless of film type, all characteristic curves are composed of five regions: D-min, the toe, the straight-line portion, the shoulder and D-max.

Exposures less than at A on negative film or greater than at A on reversal film will not be recorded as changes in density. This constant density area of a black-and-white film curve is called base plus fog. In a color film, it is termed minimum density or D-min.

The toe (A to B), as shown in Figure 9, is the portion of the characteristic curve where the slope (or gradient) increases gradually with constant changes in exposure (log H).

The straight-line (B to C), Figure 10, is the portion of the curve where the slope does not change; the density change for a given log-exposure change remains constant or linear. For optimum results, all significant picture information is placed on the straight-line portion.

The shoulder (C to D), Figure 11 , is the portion of the curve where the slope decreases. Further changes in exposure (log H) will produce no increase in density because the maximum density (D-max) of the film has been reached.

Base density is the density of fixed-out (all silver removed) negative- positive film that is unexposed and undeveloped. Net densities produced by exposure and development are measured from the base density. For reversal films, the analogous term of D-min describes the area receiving total exposure and complete processing. The resulting density is that of the film base with any residual dyes.

Fog refers to the net density produced during development of negative- positive films in areas that have had no exposure. Fog caused by development may be increased with extended development time or increased developer temperatures. The type of developing agent and the pH value of the developer can also affect the degree of fog. The net fog value for a given development time is obtained by subtracting the base density from the density of the unexposed but processed film. When such values are determined for a series of development times, a time-fog curve ( Figure 12) showing the rate of fog growth with development can be plotted.


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Curve Values

You can derive additional values from the characteristic curve that not only illustrate properties of the film but also aid in predicting results and solving problems that may occur during picture-taking or during the developing and printing processes.

Speed describes the inherent sensitivity of an emulsion to light under specified conditions of exposure and development. The speed of a film is represented by a number derived from the film's characteristic curve.

Contrast refers to the separation of lightness and darkness (called "tones") in a film or print and is broadly represented by the slope of the characteristic curve. Adjectives such as flat or soft and contrasty or hard are often used to describe contrast. In general, the steeper the slope of

Figure 9

Figure 10

Figure 11



the characteristic curve, the higher the contrast. The terms gamma and average gradient refer to numerical means for indicating the contrast of the photographic image.

Gamma is the slope of the straight-line portion of the characteristic curve or the tangent of the angle (a) formed by the straight line with the horizontal. In Figure 5, the tangent of the angle (a) is obtained by dividing the density increase by the log exposure change. The resulting numerical value is referred to as gamma.

Gamma does not describe contrast characteristics of the toe or the shoulder. Camera negative films record some parts of scenes, such as shadow areas, on the top portion of the characteristic curve. Gamma does not account for this aspect of contrast.

Average gradient is the slope of the line connecting two points bordering a specified log-exposure interval on the characteristic curve. The location of the two points includes portions of the curve beyond the straight-line portion. Thus, the average gradient can describe contrast characteristics in areas of the scene not rendered on the straight-line portion of the curve. Measurement of an average gradient extending beyond the straight-line portion is shown in Figure 13.

Curves for a Development-Time Series on a Typical Black and White Negative Film

Figure 12

Average Gradient Determination



The particular gamma or average gradient value to which a specific black-and-white film is developed differs according to the properties and uses of the film. Suggested control gamma values are given on the data sheets for black-and-white negative and positive films.

If characteristic curves for a black-and-white negative or positive film are determined for a series of development times and the gamma or average gradient of each curve is plotted against the time of development, a curve showing the change of gamma or average gradient with increase development is obtained. You can use the time-gamma curve ( Figure 14) to find the optimum developing time to produce the control gamma values recommended in the data sheet (or any other gamma desired).

Black-and-white reversal and all color film processes are not controlled by using gamma values.

Flashing camera films to lower contrast is a technique 3 that involves uniformly exposing film before processing to lower its overall contrast. It's used with some color films. It is actually an intentional light fogging of the film. You can make the flashing exposure before or after the subject exposure, either in a camera or in a printer. The required amount of exposure and the color of the exposing light depends on the effect desired, the point at which the flashing exposure is applied, the subject of the main exposure, and the film processing. Because of potential latent image changes, a flashing exposure just prior to processing is the preferred method.

Figure 13



This fairly common practice is often used to create a closer match of two films' contrast characteristics when they are intercut. The hypothetical characteristic curves in Figure 15 show what occurs when one film is flashed to approximately match another film's characteristic curve. The illustration has been simplified to show an ideal matching of the two films. In practice, results will depend on the tests run using the specific films intended for a production.

Some film productions use flashing (called "creative flashing") to alter the contrast of the original camera negative of a particular scene to create a specific effect-making pastels from more saturated colors, enhancing shadow detail, and the like. Further discussion of this type of flashing is presented in "Creative Post-Flashing Technique for the The Long Goodbye," American Cinematographer Magazine, March 1973.

Figure 14 Figure 15




WEDNESDAY, JULY 31

Color Sensitivity and Spectral Sensitivity area 12

The term color sensitivity is used on data sheets for some black-and-white films to describe the portion of the visual spectrum to which the film is sensitive. All black-and-white camera films are panchromatic (sensitive to the entire visible spectrum). Some laboratory films are also panchromatic: Eastman Fine Grain Duplicating Panchromatic Negative Film, Eastman Panchromatic Separation Film, and Eastman High Contrast Panchromatic Film.

Some films, called orthochromatic, are sensitive mainly to the blue-and- green portions of Lhe visible spectrum. Eastman Direct MP, Eastman Reversal BW Print, and Eastman Sound Recording II Films are all orthochromatic laboratory or print films.

Films used exclusively to receive images from black-and-white materials are blue-sensitive: Eastman Fine Grain Release Positive Film, Eastman High Contrast Positive Film, and Eastman Fine Grain Duplicating Positive Film.

One film is sensitive to blue light and ultraviolet radiation: Eastman Television Recording Film. The extended sensitivity in the ultraviolet region of the spectrum permits the film to respond to the output of cathode- ray tubes.

While color films and panchromatic black-and-white films are sensitive to all wavelengths of visible light, rarely are two films equally sensitive to all wavelengths. Spectral sensitivity describes the relative sensitivity of the emulsion to the spectrum within the film's sensitivity range. The photographic emulsion has inherently the sensitivity of photosensitive silver halide crystals. Itese crystals are sensitive to high-energy radiation, such as X -rays, gamma rays, ultraviolet radiation and blue-light wavelengths (blue- sensitive black-and-white films). In conventional photographic emulsions, sensitivity is limited at the short (ultraviolet) wavelength end to about 250 nanometers (nm) because the gelatin used in the photographic emulsion absorbs much ultraviolet radiation. The sensitivity of an emulsion to the longer wavelengths can be extended by the addition of suitably chosen dyes.

By this means, the emulsion can be made sensitive through the green region (orthochromatic black-and-white films), through the green and red regions (color and panchromatic black-and-white films), and into the near-infrared region of the spectrum (infrared-sensitive film). See Figure 16.

Three spectral sensitivity curves are shown for color films-one each for the red-sensitive (cyan-dye forming), the green-sensitive (magenta-dye forming), and the blue-sensitive (yellow-dye forming) emulsion layers. One curve is shown for black-and-white films. The data are derived by exposing the film to calibrated bands of radiation 10 nanometers wide throughout the spectrum, and the sensitivity is expressed as the reciprocal of the exposure (ergs/cm2) required to produce a specified


Page 1 of 4KODAK: Color Sensitivity and Spectral Sensitivity


density. The radiation expressed in nanometers is plotted on the horizontal axis, and the logarithm of sensitivity is plotted on the vertical axis to produce a spectral-sensitivity curve, as shown in Figure 17.

Equivalent neutral density (END)-When the amounts of the components of an image are expressed in this unit, each of the density figures tells how dense a gray that component can form.

Because each emulsion layer of a color film has its own speed and contrast characteristics, equivalent neutral density (END) is derived as a standard basis for comparison of densities represented by the spectral- sensitivity curve. For color films, the standard density used to specify spectral sensitivity is as follows:

For reversal films, END = 1.0 For negative films, direct duplicating, and print films, END= 1.0 above D -min.

Spectral -Dye-Density Curves area 13

Proessing exposed color film produces cyan, magenta, and yellow dye images in the three separate layers of the film. The spectral-dye-density curves (illustrated in Figure 18) indicate the total absorption by each color dye measured at a particular wavelength of light and the visual neutral density (at 1.0) of the combined layers measured at the same wavelengths.

Spectral-dye-density curves for reversal and print films represent dyes normalized to form a visual neutral density of 1.0 for a specified viewing and measuring illuminant. Films which are generally viewed by projection are measured with light having a color temperature of 5400 K. Color-

Figure 16



masked films have a curve that represents typical dye densities for a mid-scale neutral subject.

The wavelengths of light, expressed in nanometers (nm), are plotted on the horizontal axis, and the corresponding diffuse spectral densities are plotted on the vertical axis. Ideally, a color dye should absorb only in its own region of the spectrum. All color dyes in use absorb some wavelengths in other regions of the spectrum. This unwanted absorption, which could prevent satisfactory color reproduction when the dyes are printed, is corrected in the film's manufacture.

In color negative films, some of the dye-forming couplers incorporated in the emulsion layers at the time of manufacture are colored and are evident in the D-min of the film after development. These residual couplers provide automatic masking to compensate for the effects of unwanted dye absorption when the negative is printed. This explains why negative color films look orange.

Since color reversal films and print films are usually designed for direct projection, the dye-forming couplers must be colorless. In this case, the couplers are selected to produce dyes that will, as closely as possible, absorb in only their respective regions in the spectrum. If these films are printed, they require no printing mask.

Figure 17



Figure 18




WEDNESDAY, JULY 31

Image Structure

The sharpness of image detail that a particular film type can produce cannot be measured by a single test or expressed by one number. For example, resolving-power-test data gives a reasonably good indication of image quality. However, because these values describe the maximum resolving power a photographic system or component is capable of, they do not indicate the capacity of the system (or component) to reproduce detail at other levels. For more complete analyses of detail quality, other evaluating methods, such as the modulation-transfer function and film granularity, are often used. An examination of the modulation-transfer curve, RMS granularity, and both the high- and low-contrast resolving power listings will provide a good basis for comparison of the detail-imaging qualities of different films.

Modulation-Transfer Curve area 14

Modulation transfer relates to the ability of a film to reproduce images of different sizes. The modulation-transfer curve describes a film's capacity to reproduce the complex spatial frequencies of detail in an object. In physical terms, the measurements evaluate the effect on the image of light diffusion within the emulsion. First, film is exposed under carefully controlled conditions to a series of special test pattems, similar to that illustrated in (a) of Figure 19. After development, the image (b) is scanned in a microdensitometer to produce trace (c).

The resulting measurements show the degree of loss in image contrast at increasingly higher frequencies as the detail becomes finer. These losses in contrast are compared mathematically with the contrast of the portion of the image unaffected by detail size. The rate of change or "modulation" (M) of each pattern can be expressed by this formula in which E represents exposure:

Figure 20Image (b) of a sinusoidal test object (a) recorded on a photographic emulsion and a microdensitometer tracing (c) of the image.

M = E max - E min


Page 1 of 2KODAK: Image Structure


When the microdensitometer scans the test film, the densities of the trace are interpreted in terms of exposure, and the effective modulation of the image (Mi) is calculated. The modulation-transfer factor is the ratio of the modulation of the developed image to the modulation of the exposing pattern (Mo), or Mi/Mo. This ratio is plotted on the vertical axis (logarithmic scale) as a percentage of response. The spatial frequency of the patterns is plotted on the horizontal axis as cycles per millimeter. Figure 20 shows two such curves. At lower magnifications, the test film represented by curve A appears sharper than that represented by curve B; at very high magnifications, the test film represented by curve B appears sharper.

All of the photographic modulation-transfer curves in the data sheets were determined using a method similar to that specified by ANSI Standard PH2.39-1977. The films were exposed with the specified illuminant to spatially varying sinusoidal test patterns having an aerial-image modulation of a nominal 35 percent at the image plane, with processing as indicated. In practice, most photographic modulation-transfer values are influenced by development adjacency effects and are not exactly equivalent to the true optical modulation-transfer curve of a particular photographic product.

Modulation-transfer measurements can also be made for the non -film components in a photographic system such as cameras, lenses, printers, etc, to analyze or predict the sharpness of the entire system. By multiplying the responses for each ordinate of the individual curves, you can combine the modulation-transfer curve for a film with similar curves for an optical system to calculate the modulation-transfer characteristics of the entire system.

E max + E min

Figure 20


Page 2 of 2KODAK: Image Structure


WEDNESDAY, JULY 31

Graininess and Granularity area 15

The terms graininess and granularity are often confused or even used as synonyms in discussions of silver or dye-deposit distributions in photographic emulsions. The two terms refer to two distinctly different ways of evaluating the image structure. When a photographic image is viewed with sufficient magnification, the viewer experiences the visual sensation of graininess, a subjective impression of nonuniformity in an image. This nonuniformity in the image structure can also be measured objectively with a rnicrodensitometer. This objective evaluation measures film granularity.

Motion picture films consist of silver halide crystals dispersed in gelatin (the emulsion) which is coated in thin layers on a support (the film base). T'he exposure and development of these crystals forms the photographic image, which is, at some stage, made up of discrete particles of silver. In color processes, where the silver is removed after development the dyes form dye clouds centered on the sites of the developed silver crystals. The crystals vary in size, shape, and sensitivity, and generally are randomly distributed within the emulsion. Within an area of uniform exposure, some of the crystals will be made developable by exposure; others will not.

The location of these crystals is also random. Development usually does not change the position of a grain, so the image of a uniformly exposed area is the result of a random distribution either of opaque silver particles (black- and-white film) or dye clouds (color film), separated by transparent gelatin (Figures 21 and 22).

Although the viewer sees a granular pattern, the eye is not necessarily seeing the individual silver particles, which range from about 0.002 mm down to about a tenth of that size.

At magnifications where the eye cannot distinguish individual particles, it

Figure 21 Figure 22Grains of silver halide are randomly distributed in the emulsion when it is made. This photomicrograph of a raw emulsion shows silver halide crystals.

Silver is developed or clouds of dye formed at the sites occupied by the exposed silver halide. Contrary to widely held opinion, there is little migration or physical joining of individual grains. Compare the distribution of silver particles in this photomicrograph with the undeveloped silver halide in Figure 21.


Page 1 of 6KODAK: Graininess and Granularity


resolves random groupings of these particles into denser and less dense areas. As magnification decreases, the observer progressively associates larger groups of spots as new units of graininess. The size of these compounded groups gets larger as the magnification decreases, but the amplitude (the difference in density between the darker and the lighter areas) decreases. At still lower magnifications, the graininess disappears altogether because no granular structure can be seen ( Figure 23).

Randomness is a necessary condition for the phenomenon. If the particles were arranged in a regu;ar pattern like the halftone dot pattem used in graphic arts, no sensation of graininess would be created. When a halftone is viewed at a magnification sufficient for the dots to be distinguished, the eye notices the pattern and does not group dots into new patterns. Even though the dot pattern can be seen, the eye does not perceive graininess because the pattern is regular, not random (Figure 24). At lower magnifications-at which the dots can no longer be resolved-the awareness of pattern ceases, and the image areas appear uniform.

Figure 23(a) A 2.5X enlargement of a negative shows no apparent graininess. (b) At 20X, some graininess shows. (c) When a segement of the negative is inspected at 60X, the individual silver grains strt to become distinguishable. (d) With 400X magnification, the discrete grains are easily seen. Note that surface grains are in focus while grains deeper in the emulsion are out of focus. The apparent "clumping" of silver grains is actually caused by overlap of grains at different depths when viewed in two-dimensional projection. (e) The makeup of individual grains takes different forms. This filamentary silver, enlarged by an electron microscope, appears as a single opaque grain at low magnification.



When you view a random pattem of small dots magnified enough to resolve the individual dots, you do not perceive an orderly or intelligible pattem. When the magnification is decreased so the dots cannot be resolved, they appear to blend together to form an image whose surface is nonuniform or grainy.

Measuring RMS Granularity

The attributes of the photographic image which cause the human eye to perceive graininess can also be measured (and simulated) by an electro- optical system in a microdensitometer. These measurements are analyzed statstically to provide numerical values that correlate with the visual impression of graininess. The two major advantages of objective measurement are that instruments can be devised to make rapid and precise measurements and that these measurements can be manipulated readily by mathematical means.

Ordinary densitometers measure density over areas much larger than those of individual silver particles. Since there are so many particles in the aperture of an ordinary densitometer, small variations in the number of particles measured will not affect the reading.

Just as higher magnification increases the apparent graininess, a decrease in the aperture produces higher granularity values. When the aperture of the densitometer is considerably reduced, fewer particles are included and a small change in their number is recorded as a variation in density. Analysis of the magnitude of these variations gives a statistical measure of the granularity of a sample.

In practice, an area of apparently uniform density is continuously scanned by the small aperture usually 48 nanometers in diameter (see Figure 25). The transmitted light registers on a photo-sensitive pickup,

Figure 24If the uniform dot pattern of a conventional halftone is used to reproduce a scene, the eye accepts the image as a smooth, continuous-tone rendition (a). This happens because the dots are regularly spaced. However, when the halftone dots are distributed randomly in an area to reproduce a scene (b) the image looks "grainy." Graininess in the image is due, in part, to the random distribution of the individual elements which make up that image.



and the current produced is then fed to a meter calibrated to read the standard deviation of the random-density fluctuations (see Figure 26).

Standard deviation describes the distribution of a group of values (in this case, variations in density) about their average. The square root (R) of the arithmetic mean (M) of the squares (S) of the density variations is calculated-hence, the term RMS granularity. For ease of comparison, this small decimal number is multiplied by a factor of 1,000, yielding a small whole number, typically between 5 and 50.

The RMS granularity instrument used at Kodak is calibrated to measure American National Standard (PH2.19-1976) diffuse visual density. The

Figure 25A large aperture "sees" a vast number of individual silver grains. Therefore, small local fluctuations have practically no effect on the density it records. Small apertures (about one twentieth of the larger aperture diameter) detect random differences in grain distribution when they sample the large "uniform" area.

Figure 26The signal from a continuous density scan of a grainy emulsion appears the same as random electrical noise when displayed on an oscilloscope. The rms voltmeter gives a direct readout of "noise level."



about 0.6 to 0.9). The light tones of the print are on the toe of the characteristic curve where the slope is very much lower than unity. Hence, the contrast with which the graininess is reproduced is very low-decreasing its visibility. In dark tones, the eye is less able to distinguish graininess. The eye easily detects density differences as low as 0.02 in the average highlight density, but can detect density differences only on the order of 0.20 in the average shadow density. In the midtones, where the slope of the curve is constant, the print material has its maximum contrast and the eye can more readily distinguish small density differences; therefore, the granularity can be most easily detected by the eye as graininess.

Another factor in perceiving graininess is the amount of detail in a scene. Graininess is most apparent in large areas with fairly uniform densities and is much less evident in areas full of fine detail or motion.

It is difficult to predict the magnification at which projected print images will be viewed since both the projection magnification and the distance from the observer to the screen can very. Both factors affect the picture magnification, and thus the graininess.

When a motion picture film is seen at great magnification (as from a front-row theater seat), the viewer may be aware of grains "boiling" or "crawling" in uniform areas of the image. This sensation is caused by the frame-to-frame changes of grain positions, which make graininess more noticeable in a motion picture than in a still photograph. Conversely, the moving image tends to distract the viewer's attention away from this sensation, and graininess is, therefore, usually noticed only in static scenes.




WEDNESDAY, JULY 31

Resolving Power area 16

The resolving power of a film emulsion refers to its ability to record fine detail. It is measured by photographing resolution charts or targets under exacting test conditions. The parallel lines on resolution charts are separated from each other by spaces the same width as the lines. The chart contains a series of graduated parallel-line groups, each group differing from the next smaller or next larger by a constant factor. The targets are photographed at a great reduction in size, and the processed image is viewed through a microscope. The resolution is measured by a visual estimate of the number of lines per millimeter that can be recognized as separate lines.

The measured resolving power depends on the exposure, the contrast of the test target, and, to a lesser extent, the development of the film. The resolving power of a film is greatest at an intermediate exposure value, falling off greatly at high- and low-exposure values. Obviously, the loss in resolution that accompanies under- or over-exposure is an important reason for observing the constraints of a particular film when making exposures.

Resolution also depends on the contrast of the image, hence, the contrast of the target. Test exposures are usually made with both a high-contrast (luminance ratio 1000: 1) and a low-contrast (1.6:1) target. A film resolves finer detail when the image contrast is higher. Both high- and low-contrast resolving-power values are determined according to a method sirnilar to the one described in ANSI No. PH2.33-1969 1R1976). "Method for Determining the Resolving Power of Photographic Materials," are given on the data sheets. The resolving power reported is based on film exposed and processed as recommended.

The maximum resolution obtainable in practical photographic work is limited both by the camera lens and by the film. The formula often used to predict the resolution of a camera original is

RS = Resolution of the system (lens + film)

RF = Resolution of the film

RL = Resolution of the lens

In practice, other external factors, such as camera movement, focus, aerial haze, etc, also decrease the resolution from the possible maximum.

1 One lux is the illumination produced by one standard candle from a distance of 1 meter. When a film is exposed for 1 second to a standard candle 1 meter distant, it receives 1 lux-sec of exposure.

2 Zwick, D., "The Meaning of Numbers to Photographic Parameters" Journal of the Society of Photo-Optical Instrumentation Engineers, Volume 4 (1966), pages 205-211.

1 RS2

= 1

RF2 +

1 RL2


Page 1 of 2KODAK: Resolving Power


WEDNESDAY, JULY 31

Physical Characteristics

l Film Base l Antihalation Backing l Edge Numbers l Dimensional Change Characteristics

¡ Temporary Size Change n Moisture n Temperature n Rates of Temporary Change n Swell During Processing

¡ Permanent Size Change n Raw Stock Shrinkage n Processing Shrinkage n Aging Shrinkage

l Other Physical Characteristics ¡ Curl ¡ Buckling and Fluting



Page 1 of 1KODAK: Physical Characteristics

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WEDNESDAY, JULY 31

Film Base area 17

The film base is the plastic support that carries the light-sensitive emulsion. Requirements for a suitable film base include optical transparency, freedom from optical imperfections, chemical stability, photographic inertness, and resistance to moisture and processing chemicals. Mechanical strength, resistance to tearing, flexibility, dimensional stability, and freedom from physical distortion are also important factors in processing, printing, and projection.

Two general types of film base are currently used -cellulose triacetate esters and a synthetic polyester polymer known as ESTAR Base. Cellulose triacetate film base is made by combining the cellulose triacetate with suitable solvents and a plasticizer. Most current Kodak and Eastman Motion Picture Films are coated on a cellulose triacetate base.

ESTAR Base, a polyethylene terephthalate polyester, is used for some Kodak and Eastman Motion Picture Films (mostly intermediate and print films) because of its high strength, chemical stability, toughness, tear resistance, flexibility, and dimensional stability. The greater strength of ESTAR Base permits the manufacture of thinner films that require less room for storage. ESTAR Base films and other polyester base films, cannot be successfully spliced with readily available commercial film cements. You can splice these films with a tape splicer or with a splicer that uses an ultrasonic or an inductive beating current to melt and fuse the film ends.

Antihalation Backing

Light penetrating the emulsion of a film can be reflected from the base- emulsion interface back into the emulsion. As a result, there is a secondary exposure causing an undesirable reduction in the sharpness of the image and some light scattering, called halation, around images of bright objects. See Figure 27. A dark layer coated on or in the film base will absorb and minimize this reflection, hence it is called an antihalation layer. Three methods of minimizing halation are commonly used:

Rem Jet: A black-pigmented, nongelatin layer on the back of the film base serves as an antihalation and antistatic layer. This layer is removed during photographic processing.

Antihalation undercoating: A silver or dyed gelatin layer directly beneath the emulsion is used on some thin emulsion films. Any color in this layer is removed during processing. This type of layer is particularly effective in preventing halation for high-resolution emulsions. An antistatic and/or anticurl layer may be coated on the back of the film base when this type of antihalation layer is used.


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Dyed film base : Film bases, especially polyester, can also transmit or pipe light that strikes the edge of the film. This light can travel inside the base and fog the emulsion (Figure 27). A neutral-density dye is incorporated in some film bases and serves to both reduce halation and prevent light piping. This dye density may vary from a just detectable level to approximately 0.2. The higher level is used primarily for halation protection in black-and-white negative films on cellulosic bases. Unlike fog, the gray dye does not reduce the density range of an image, because it, like a neutral- density filter, adds the same density to all areas. It has, therefore, a negligible effect on picture quality.

Figure 27Light Piping


Page 2 of 2KODAK: Film Base


WEDNESDAY, JULY 31

Edge Numbers

Edge numbers (also called key numbers or footage numbers) are placed at regular intervals along the film edge for convenience in frame-for-frame matching of the camera film to the workprint. The numbers are printed along one edge outside the perforations on 35 mm film and between the perforations on 35 mm film and between the perforations on 16 mm film. The numbers are sequential, usually occurring every 16 frames (every 12 inches) on 35 mm film and every 20 frames (every 6 inches) on 16 mm film. In a few instances, edge numbers on 16 mm films are located every 40 frames (12 inches).

All Kodak camera film is edge numbered at the time of manufacture in one of two ways:

Latent Image: The film edge is exposed by a printer mounted at the perforator to produce an image visible only on processed film. The five or seven digits are sequential and will change every 16 (35 mm) or 20 (16 mm) frames. The cluster of numbers and letters to the left of the sequential numbers are a manufacturer's code for the type of product, the perforator, and the equipment used to produce the product. All Kodak 16 mm and 35 mm camera color film is latent-image edge numbered ( Figure 28).

Visible Ink Image: During manufacturing, the filrn stock is numbered with a visible ink. Again, this process is performed at the perforators. The ink, unaffected by photographic chemicals, is printed on the emulsion surface of the film. The numbers are visible on both the raw stock and the processed film. In Figure 29, the visible ink edge numbering will be more visible after processing. All 35 mm Kodak black-and-white motion picture camera films have ink edge numbers. The letter "C" is a manufacturer's product identification.

A third method of applying edge numbering is very often used by commercial motion picture labs. There the film is numbered on the base side, generally with yellow ink. This numbering does not interfere with the manufacturer's edge numbers because the lab numbers are ordinarily printed on the opposite edge of the film. Normally, both the original camera film and the workprint are edge numbered identically for later ease in matching the two.

Figure 30 is a sample of Eastman EKTACHROME Video News Film 7240 (Tungsten), edge numbered by a laboratory in New York City.

With double-system sound, both the film and the magnetic tape are often edge numbered by the lab for ease of editing.

Figure 28Latent image edge numbering


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In 1990, Eastman Kodak Company introduced a new edge-numbering system that will eventually be included on all Eastman camera negative films, both black-and-white and color. The new system incorporates Eastman KEYKODETM; numbers which are machine readable in bar code. A variety of scanners can read this bar code in the same way that the bar code on most products in supermarkets is read by a scanner in the checkout line. The human-readable key numbers are similar to previous edge numbers, but are easier to read. In this improved format, the key number consists of 12 highly legible characters printed at the familiar one-foot, 64 perforation interval. The KEYKODETM; number incorporates the same human-readable number, but in a bar code. See Figures 31 and 32.

Eastman 16 mm Edgeprint Format

Featuring KEYKODETM Numbers - Figure 31, 32

Figure 29 Figure 30Visible ink edge numbering Laboratory applied edge numbering

Home | Search | Service & Support | Visit shop @ kodak, the online store | Careers Copyright © Eastman Kodak Company, 1994-2002 and Privacy Practices (updated 14-Sep-2001).

Page 2 of 2KODAK: Edge Numbers

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WEDNESDAY, JULY 31

Dimensional Change Characteristics

Motion picture film dimensions are influenced by variations in environmental conditions. The film swells during processing, shrinks during drying, and continues to shrink at a decreasing rate throughout its life. These dimensional changes in film are either temporary (reversible) or permanent (irreversible). Temporary size changes are caused by a modification in the moisture content or the temperature of the film. The extent of both temporary and permanent size alterations is largely dependent upon the film support. However, since the emulsion is considerably more hygroscopic than the base, it also has a marked influence on dimensional variations caused by humidity. Permanent shrinkage of film on cellulose triacetate support is due to loss of residual solvents or plasticizer, and, to a slight extent, the gradual elimination of strains introduced during manufacture or processing. ESTAR Base has no residual solvent or plasticizer and absorbs less moisture than cellulose triacetate; consequently, its size changes are considerably less. Some permanent shrinkage occurs in aging of raw stock processing, and aging of processed film. Values for the dimensions change characteristics of current Kodak and Eastman Motion Picture Films are given in the table below.

Approximate Dimensional Change Characteristics of Current Kodak and Eastman Motion Picture Films

Film Base

Humidity Coefficient of Expansion % per 1% RH

(a)

Thermal Coefficient of Expansion % per 1ºF (b)

Processing Shrinkage %

(c)

Potential Aging

Shrinkage % (d)

Length Width Length Width Length Width Length Width

Black-and-white camera

negative, duplicating

negative, color negative, color internegative,

color intermediate

and EKTACHROME Camera Films

Triacetate 0.007 0.008 0.0025 0.0035 0.03 0.05 0.2 0.25

Black-and-white release positive,

duplicating positive,

variable-density sound recording

and Eastman Color Print

Triacetate 0.005 0.006 0.0025 0.0035 0.03 0.05 0.4 0.5

Eastman Color Print and

Eastman Color Reversal

Intermediate

ESTAR 0.003 0.003 0.001 0.001 0.02 0.02 0.04 0.04

(a) Measured between 15% and 50% RH at 21ºC (70 ºF) (b) Measured between 49ºC (12 ºF) and 21ºC (70 ºF) at 20% RH (c) Tray processing measured at 21ºC (70ºF) and 50% RH after preconditioning at low relative humidity


Page 1 of 2KODAK: Dimensional Change Characteristics


WEDNESDAY, JULY 31

Temporary Size Change

Moisture. Relative Humidity (RH) of the air is the major factor affecting the moisture content of the film, thus governing the temporary expansion or contraction of the film (assuming constant temperature). For camera films, the humidity coefficients are slightly higher than for positive print films. The coefficients given in the table above are averages for the range of 15- to 50-percent RH, where the relationship between film size and relative humidity is approximately linear. For ESTAR Base films, this coefficient is larger at lower humidity ranges, and smaller at higher humidity ranges. When a given relative humidity level is approached from above, the exact dimensions of a piece of film on cellulose triacetate support may be slightly larger than when the level is approached from below. The opposite is true for ESTAR Base films, which will be slightly larger when the film is previously conditioned to a lower humidity than it would be if conditioned to a higher humidity.

Temperature. Photographic film expands with heat and contracts with cold in direct relationship to the film's thermal coefficient. The thermal coefficients for current Kodak and Eastman Motion Picture Films are listed in the previous table.

Rates of Temporary Change. Following a shift in the relative humidity of the air surrounding a single strand of film, humidity size alterations occur rapidly in the first 10 minutes and continue for about an hour. If the film is in a roll, this time will be extended to several weeks because the moisture must follow a longer path. In the case of temperature variations, a single strand of film coming in contact with a hot metal surface, for example, will change almost instantly. A roll of film, on the other hand, requires several hours to alter size.

Swell during Processing. All motion picture films swell during photographic processing and shrink during drying. The swell of triacetate films is initially rapid and depends upon the temperature of the processing solutions, time, and film tension. Acetate films swell more in the widthwise than in the lengthwise direction, and negative films swell more than print films. The change for ESTAR Base films is much smaller. The effects of drying upon the final dimensions are discussed in the section on permanent size change.

Swell During Processing

Swell %

Film Type Base Length WidthNegative Triacetate 0.4 0.6

Positive - Black-and-White and Color

Triacetate 0.3 0.5

Reversal-ColorAcetate-

Propionate0.6 0.8

Positive-Color ESTAR 0.05 0.05


Page 1 of 3KODAK: Temporary Size Change


Permanent Size Change Permanent size change is the summation of the shrinkage of the raw film, the size change due to processing, and the shrinkage of the processed film.

Raw Stock Shrinkage. Immediately after slitting and processing, the unexposed motion-picture film is placed in cans that are sealed with tape. Until the film is removed from the can, solvent loss from triacetate film is extremely low. The lengthwise shrinkage will rarely exceed 0.5 percent during the first 6 months in a 1000-foot can of 35 mm film. ESTAR Base films will not shrink more than 0.2 percent while in a taped can.

Processing Shrinkage. The net effect of processing triacetate base film is normally slight shrinkage (see table ) unless the film has been stretched. Some commercial processing machines have sufficiently high tension to stretch the wet film (particularly 16 mm film); consequently, a lower net processing shrinkage or even a slight permanent stretch may result. Because of its greater strength and resistance to moisture, the overall size change of ESTAR Base films is much less.

Aging shrinkage. It is important that motion picture negatives, internegatives, and color originals have low aging shrinkage so that you can make satisfactory prints or duplicates even after many years of storage. With motion picture positive film intended for projection only, shrinkage is not especially critical because it has little effect on projection.

The rate at which aging shrinkage occurs depends upon the conditions of storage and use. Shrinkage is hastened by high temperature and, in the case of triacetate films, by high relative humidity which aids the diffusion of solvents from the film base.

The potential aging shrinkage of current motion-picture films is given in this table. In the case of processed negatives made on stock manufactured since June 1954, the potential lengthwise shrinkage of about 0.2 percent is generally reached within the first two years and almost no further shrinkage occurs thereafter. This very small net change is a considerable improvement over the shrinkage characteristics of negative materials available before 1954 and permits good printing even after long periods of keeping.

The lengthwise shrinkage of release prints made on triacetate supports is



about 0.1 to 0.3 percent for 35 mm film and 0.1 to 0.4 percent for 16 mm film during the first two years. Higher shrinkage can occur over a longer period, as indicated in this table. Shrinkage of films on ESTAR Base is unlikely to exceed 0.04 percent.

Although aging shrinking of motion picture films is a permanent size change, humidity and thermal size changes can either increase or decrease the observed size change.




WEDNESDAY, JULY 31

Other Physical Characteristics

Aside from image quality considerations, other factors can affect the satisfactory performance of motion picture film.

Curl

Photographic-film curl is defined as the departure from flatness of photographic film. Curl toward the emulsion is called positive while curl away from the emulsion is termed negative. Although the curl level is established during manufacture, it is influenced by the relative humidity during use or storage, processing and drying temperatures, and the winding configuration.

At low relative humidities, the emulsion layer contracts more than the base generally producing positive curl. As the relative humidity increases, the contractive force of the emulsion layer decreases and the inherent curl of the support becomes dominant.

Film wound in rolls tends to assume the lengthwise curl conforming to the curve of the roll. When a strip of this curled film is pulled into a flat configuration, the lengthwise curl is transformed into a widthwise curl.

Buckling and Fluting

Very high or low relative humidity can also cause abnormal distortions of film in rolls. Buckling, caused by the differential shrinkage of the outside edges of the film, occurs if a tightly wound roll of film is kept in a very dry atmosphere. Fluting, the opposite effect, is caused by the differential swelling of the outside edges of the film; it occurs if the roll of film is kept in a very moist atmosphere. To avoid these changes, do not expose the film rolls to extreme fluctuations in relative humidity.

Aditional reading on "Physical Characteristics of film."

Adelstein, P. Z. and Calhoun, J. M., "Interpretation of Dimensional Changes in Cellulose Ester Base Motion Picture Films," Journal of the SMPTE , 69:157-63, March 1960.

Adelstein, P. Z. Graham, C. L., and West, L. E., "Preservation of Motion Picture Color Films Having Permanent Value," Journal of the SMPTE , 79:1011-1018, November 1970.

Figure 33


Page 1 of 2KODAK: Other Physical Characteristics


Calhoun, J. M "The Physical Properties and Dimensional Behavior of Modon Picture Films," Journal of the SMPTE , 43:227-66, October 1944.

Fordyce, C. R., "Improved Safety Motion Picture Film Support," Journal of the SMPTE , 51:331 -50, October 1948.

Fordyce, C. R., Calhoun, J. M., and Moyer, E. E., "Shrinkage Behavior of Motion Picture Film," Journal of the SMPTE , 64:62 -66, February 1955.

Miller, A. J. and Robertson, A. C., "Motion Picture Film-Its Size and Dimensional Characteristics," Journal of the SMPTE, 74:3-1 1, January 1965.

Neblette, C. B., "Photography-Its Materials and Process," Chapter 11, D. VanNostrand Co., Inc., 1962


Page 2 of 2KODAK: Other Physical Characteristics


WEDNESDAY, JULY 31

Storage of Raw and Exposed Film

l Raw Stock in Original Package ¡ Temperature ¡ Radiation ¡ Gases and Vapors ¡ Relative Humidity ¡ Handling

l Unprocessed Film before and after Exposure ¡ General Concerns ¡ Temperature ¡ Gases and Radiation ¡ Relative Humidity ¡ Handling

Storage of Raw and Exposed Film (18)

The sensitometric characteristics of virtually all unprocessed photographic materials gradually change with time, causing loss in sensitivity, a change in contrast, a growth in fog level, or possibly all three. In color films, the rates at which the various color-sensitive layers respond are not necessarily the same, thus the color balance of the material can also change. Improper storage usually causes much larger changes in color quality and film speed than do variations in manufacturing. Scrupulous control of temperature and humidity, thorough protection from harmful radiation and gases, and careful handling are important to long, useful film life.

This section explains how to store raw film stock and exposed but unprocessed film. This chart summarizes optimum storage conditions.

Raw Stock in Original Package

Temperature In general, the lower the temperature at which a film is stored, the slower will be its rate of sensitometric change during aging. For periods up to six months, motion picture raw stock should be stored at a temperature of 13ºC (55ºF) or lower during the entire storage period if optimum film properties are to be retained.

Raw stock should be stored at -18º to -23ºC (0º to -IOºF) if it must be kept longer than six months or if the film is intended for a critical use that requires uniforrn results. Sensitometric change cannot be prevented by such storage, but it will be minimized.

IMPORTANT: After removing a package of raw stock from cold storage, allow it to warm up to room temperature (70ºF +/- 5ºF) before opening the can. This will prevent telescoping of the roll during handling because of cold-induced looseness between the layers and will prevent moisture condensation and spotting of the film.

Type of Kodak Film

Warm-Up Times (Hours)

For 14ºC For 55ºC


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Radiation Do not store or ship raw stock near X-ray sources or other radioactive materials. Some scanning devices used by postal authorities and airlines may fog raw stock. Take special storage precautions in hospitals, industrial plants, and laboratories where radioactive materials are in use. Label packages of unprocessed films that must be mailed across international borders: "Contents: Unprocessed photographic film. Please do not X-ray."

Gases and Vapors Gases (such as formaldehyde, hydrogen sulfide, sulfur dioxide, ammonia, illuminating gas, engine exhaust) and vapors (from solvents, mothballs, cleaners, turpentine, mildew and fungus preventives, and mercury) can change the sensitivity of photographic emulsions. The cans in which motion picture film is packaged provide protection against some gases, but others can slowly penetrate the adhesive tape seal. Keep film away from any such contamination-for example, closets or drawers that contain mothballs-otherwise, desensitization of the silver halide grains or chemical fogging can occur.

Relative Humidity Since a small amount of vapor leakage through the closure of a taped can is unavoidable, give motion picture films additional water-vapor protection if they are to be kept longer than a month in an area having high relative humidity (70 percent or higher), such as home refrigerators or damp basements. Protect unopened rolls by tightly sealing them in a second plastic container or can.

NOTE: It is the relative humidity, not the absolute humidity, that determines the moisture content of film. Relative humidity is best measured with a sling psychrometer. In a small storage chamber, a humidity indicator, such as those sold for home use, is satisfactory.

Handling Storage rooms for motion-picture raw stock should be designed so that accidental flooding from storms, water pipes, or sewers cannot damage the product. Store all film at least 15 cm(6in.)off the floor.

Package (25ºF) Rise (100ºF) Rise

8 mm super 8 16 mm 35 mm

1 1 1 3

1 1/2 1 1/2 1 1/2

5

Short-Term (less than 6 months)

Long-Term (more than 6 months)

Temperature%

Relative Humidity

Temperature%

Relative Humidity

Raw Stock (in original

sealed cans)13ºC (55ºF) below 70

-18º to -23ºC (0º 10ºF)

-

Exposed Unprocessed

-18º to -23ºC (0º 10ºF)*

-Not Recommended (see text

below)

After removal from storage, keep sealed (in original cans) until temperature is above the dew point of outside air. (See table of warm up times.) * Exposed film should be processed as soon as possible after exposure.



Construct and insulate rooms that are artificially cooled so that moisture does not condense on the walls. If the building itself is not fireproof, install sprinklers. As indicated, control of relative humidity below 70 percent is not critical as long as the film cans remain sealed. Maintain the temperature as uniform as possible throughout the storage room by means of adequate air circulation so that sensitometric properties remain consistent, roll to roll.

Do not store film near heating pipes or in the line of sunlight coming through a window, regardless of whether the room is cool or not.

Unprocessed Film before and after Exposure

General Concerns Once you open the original package, the film is no longer protected from high relative humidities that can cause undesirable changes. Exposed footage is even more vulnerable to the effects of humidity and temperature. Therefore, process film as soon as possible after exposure.

Temperature Protect film in original packages or loaded in cameras, cartridges, magazines, on reels, and in carrying cases from direct sunlight and never leave film in closed spaces that may trap heat. The temperatures in closed automobiles, parked airplanes, or the holds of ships, for example, can easily reach 60ºC (140ºF) or more. A few hours under these conditions, either before or afer exposure, can severely affect the quality of the film. If processing facilities are not immediately available, store exposed films at -18ºC (OºF).

Gases and Radiation Keep films away from the harmful gases and radiation mentioned earlier.

Relative Humidity When handling motion-picture film in high relative humidities, it is much easier to prevent excessive moisture take-up than it is to remove it. If there are delays of a day or more in shooting, remove the magazine containing partially used film from the camera and place it in a moisture-tight dry chamber. This prevents any absorption of moisture by the film during the holding period. Immediately after exposure, return the film to its can and retape it to prevent any increase in moisture content over that picked up during actual exposure. Moisture leakage into a taped can is more serious when the can contains only a small quantity of film. When these circumstances exist, seal as many rolls as possible in a second moisture- resistant container.

Handling Handle the film strand only by the edges to avoid localized changes in film sensitivity caused by fingerprints. Folding and crimping the film also introduces local changes in sensitivity. Keep the surfaces that the film travels over clean to prevent scratching of the film's base or emulsion.

A more detailed discussion of long-term storage may be found in The Book of Film Care, Kodak Publication No. H-23.




WEDNESDAY, JULY 31

How do I know I'm ordering the right film?

How to identify the film's format, emulsion, length, and winding

Motion picture film emulsions are coated on a 54-inch-wide continuous web of film base. These 54-inch rolls constitute the master stock rolls that are slit into strips during the finishing process. Each master roll is assigned a number, and each strip also has a reference number. After slitting, the strips are perforated and cut to the designated lengths.

Kodak and Eastman Motion Picture Camera Films are then wound on cores or spools, the ends are taped, and the wound film is wrapped in black, plastic bags before being packaged in taped metal cans or box bins. The plastic bags protect the film from exposure to light, provide a high degree of cleanliness, and make the film fit snugly inside the can.

The tape used on the outside of a film can serves as a seal between the cover and body of the can. This tape is designed to resist the flow of air and moisture so that the newly manufactured film retains its original moisture content. The tape and can are both marked to identify the contents. A description of the identifying codes on tape, can label, and film appears under Film Identification.

The "rolls available" block on the data sheet describes forms in which a particular film type is available.

The first column gives the catalog number (CAT No.), perhaps the most important piece of information to know when ordering film from Kodak. The catalog number identifies a particular kind of emulsion, film format, and length to our Customer Relations Representatives. For example, CAT No. 124 6636 describes only one film package: 100 feet of Eastman Color Negative Film 5247 (35 mm), EI Winding, one row of perfs (1866 pitch), with a film identification number of ECN718.

The second column gives the film identification number, a combination of a three-letter film emulsion designation (ECN, in the example above) and a three-digit specification number (718, in this case). The number designates film width; perforation type and format; type of core, spool, or magazine; and winding. This code does not generally refer to the film length.

The last two or three columns-Description, Format (applicable only to films available in multi rank), and Perforation Type-provide the film length and the information abstracted from the specification number.

A single free copy of any film data sheet is available from this website or write: Eastman Kodak Company, Dept. 412-L, Rochester, NY 14650-0532.



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WEDNESDAY, JULY 31

Cores and Spools

KODAK and EASTMAN Motion Picture Films are available on several types of cores and spools, each appropriate to the design of the equipment in which the films are to be exposed. The films are connected to the core, or spool, in one of the following ways: (1) wound on the core indicates the film is initially started by tightly lapping several convolutions of film around the core. When the film is wound on the core, the core cannot be removed from the film except by unwinding the film; (2) core inserted indicates that the film is initially wound on a collapsible mandrel that is later removed and the core inserted in the cavity of the roll. Thus, the film is not attached to the core.

The standard core and spool types for KODAK and EASTMAN Motion Picture Films are shown and described below:

Type T Core-16 mm. Figure 34 illustrates a plastic core with a 2-inch (51 mm) outside diameter and a 1-inch (25.4 mm) diameter center hole with keyway and film slot. Normally used with 16 mm films up to 400 feet (122 m) in length, except 100 -foot (30.5 m) and 200-foot (61 m) lengths of camera negative and reversal materials, which generally come on camera spools with integral leaders and trailers for loading under subdued light.

Type Z Core-16 mm. A plastic core with a 3 -inch (76 mm) outside diameter. Contains a 1-inch (25.4 mm) diameter center hole with keyway and a film slot. Used with camera and print films in roll sizes longer than 400 feet (122 m). See Figure 35.

Type U Core-35 mm. A plastic core with a 2 -inch (51 mm) outside diameter. Contains a 1 -inch (25.4 mm) diameter center hole with keyway and a film slot. Customarily used with camera negative, sound, print, and television recording films, and positive films that are used in title cameras. Supplied in a variety of lengths. See Figure 36.

Type K Core-35 mm. A plastic core with a 3 -inch (76 mm) outside diameter. Contains a

Figure 34

Figure 35

Figure 36

Figure 37


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1-inch (25.4 mm) diameter center hole with keyway and a film slot. Used with 2000-foot (610 m), 3000-foot (914 m), 4000-foot (1219 m), and some 1000-foot (305 m) lengths of negative, sound, print, and television recording films. See Figure 37.

Type Y Core-35 mm. A plastic core with the same dimensions as the Type K Core but made of a stronger material to hold 6000-foot (1829 m) rolls of color print film. See Figure 38.

R-90 Spool -16 mm. A metal camera spool with a 3.615-inch (92 mm) flange diameter and a 1 1/4 -inch (32 mm) core diameter. Square hole with single keyway in both flanges. Center hole configuration is aligned on both flanges. The standard sales lengths for this spool are 100 feet (30.5 m) of acetate base film. Used in cameras such as the Canon and Elmo for double super 8 film and in 16 mm spool-loading cameras. See Figure 39.

R-190 Spool-16 mm. A metal camera spool with a 4.940-inch (125 mm) flange diameter and a 1 1/4 -inch (32 mm) core diameter. Square hole with single keyway, two offset round drive holes, and one elliptical hole in both flanges. Side 1 and Side 2 markings. Will accept 200 feet (61 m) of acetate base film. See Figure 40.

S-83 Spool-35 mm. A metal camera spool with a 3.657-inch (93 mm) flange diameter and a 31/32 -inch (25 mm) core diameter. Square holes with single keyway in both flanges. Center hole configuration is aligned on both flanges. Intended for 100 feet (30.5 m) of acetate base film. Used with camera negative materials. See Figure 41.

Figure 38

Figure 39

Figure 40

Figure 41


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WEDNESDAY, JULY 31

Winding

When a 16 mm roll of raw stock, perforated along one edge, is held so that the end of the film leaves the roll at the top and to the right, it is designated Winding A if the perforations are toward the observer, Winding B if the perforations are away from the observer, as shown in Figure below. Winding A films are used to make contact prints and are not intended for use in the camera. Winding B is used for camera film, to make optical prints, and on bidirectional printers.

NOTE: When requesting single-perforated film on a spool or core that has nonsymmetrical flanges (i.e., a different hole or keyway on either side), you must indicate the hole or keyway closest to the perforations and specify whether the emulsion should be wound in or out.

Film for use in 16 mm single -system sound cameras is regularlyg furnished in Winding B on 100-foot (30.5 m) and 200 -foot (61 m) spools. It is also furnished in Winding B on 400-foot (122 m) Type T cores and, occasionally, on spools.

Winding A Emulsion Side in

Winding B Emulsion Side in



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WEDNESDAY, JULY 31

Perforations

l Sizes and Shapes l Perforation Types

¡ 35 mm and 60 mm End Use ¡ 16 mm End Use

l Optimum Pitch for Printing l Projection Print Aspect Ratios



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WEDNESDAY, JULY 31

Sizes and Shapes

In the early days of 35 mm motion pictures, film perforations were round. Because these perforations were more subject to wear, the shape was changed to that now known as the Bell & Howell (BH) or 'negative' perforation. See Figure 43. This modification improved positioning accuracy and was the standard for many years. During this time, 35 mm professional motion picture cameras and optical printers were designed with registration pins that conformed to negative (BH) perforation and are still so designed to this day. Thus, camera films and many laboratory films use the negative (BH) perforations. The high shrinkage of older films on nitrate base made the negative perforation a problem on projection films because of the excessive wear and noise during projection as the sprocket teeth ticked the hold-back side of the perforations as they left the sprocket. The sharp corners also were weak points and projection life of the film was shortened. To compensate for this, a new perforation was designed with increased height and rounded corners to provide added strength. This perforation, commonly known as the KS or "positive" perforation, has since become the world standard for 35 mm projection print films.

During the period when the production of color prints involved the multiple printing of separation negatives onto a common print film, a third design, known as the Dubray-Howell perforation, was introduced. It had the same height as the negative (BH) perforation to maintain the necessary registration but had rounded corners to improve projection life. This perforation is still available for special applications and on certain films (Eastman Color Intermediate II Film 5243, for example). Because shrinkage in current films is low, the shorter perforation height poses no projection wear problems. In 1953, the introduction of CinemaScope produced a fourth type of perforation. This wide-screen projection system incorporated 35 mm film with perforations that were nearly square and smaller than the positive (KS) perforation. The design provided space on the film to carry four magnetic-sound stripes for stereophonic and surround sound. Although not widely used now, this perforation is still available on 35 mm Eastman Color Print Film.

Except for early experimentation, perforation dimensions on 16 mm and 8 mm films have remained unchanged since their introduction.

Each type of perforation is referred to by a letter identifying its shape and by a number indicating the perforation pitch dimension. Perforation pitch is the distance from the bottom edge of one perforation to the bottom edge of the next perforation. The letters BH indicate negative perforations, which are generally used on camera films, on intermediate films, and on films used in special-effect processes. The letters KS indicate positive perforations, which are used on most positive sound recording films and color print films The letters CS designate the smaller perforations used for projection prints on which additional space must be provided for multiple sound tracks in the CinemaScope process.

The designation BH 1866, for example, indicates a film having negative - type perforations with a pitch dimension of O.1866 inch (4.740 mm).

Camera films may be perforated along both edges (double perforated) or


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along only one edge (single perforated). All 35 mm camera films are double perforated. Films for single-pass 16 mm and 8 mm camera use may be single or double perforated. Single-perforated 16 mm films are often magnetically striped for single-system sound or post process sound addition. Double -perforated super 8 and regular 8 film is always suppled in 16 mm width to allow two-pass camera operation. Films used in laboratories for intermediate and release prints are supplied in a variety of perforation formats. The letter R preceded by a number designates the number of rows of perforations in a strip (1R-one row, 2R-two rows, etc.).

Some flexibility is possible in selecting double- or single-perforated film. You can use double -perforated film in cameras having a single pull-down claw. Also, you can duplicate or print footage exposed on double-perforated film on single-perforation stock if a photographic (optical) or magnetic sound track is to be added to the film. (NOTE: Do not use single- perforated film in equipment designed for double-perforated film.)

Figure 43

Perforation Type

Bell & Howell Kodak Standard 16 Tolerance +/-

Dimensions Inches mm Inches mm Inches mm Inches mm

C 0.1100 2.794 0.1100 2.794 0.0720 1.829 0.0004 0.010

D 0.0730 1.854 0.0780 1.981 0.0500 1.270 0.0004 0.010

H* 0.0820 2.08

R 0.020 0.51 0.010 0.25 0.001 0.03

* Dimension H is a calculated value



Figure 44

Perforation Type and ANSI Number

1R-2994 (PH22.109)

1R-3000 (PH22.12)

2R-2994 (PH22.110)

2R-3000 (PH22.5)

Tolerance +/-

Dimensions Inches mm Inches mm Inches mm Inches mm Inches mm

A* 0.628 15.95 0.628 15.95 0.628 15.95 0.628 15.95 0.001 0.03

B 0.2994 7.605 0.3000 7.620 0.2994 7.605 0.3000 7.620 0.0005 0.013

E 0.0355 0.902 0.0355 0.902 0.0355 0.902 0.0355 0.0355 0.0020 0.051

F 0.413 10.49 0.413 10.49 0.001 0.03

G (max) 0.001 0.03 0.001 0.03 - -

L** 29.94 760.5 30.00 762.0 29.94 760.5 30.00 762.0 0.03 0.8

* This dimension also represents the unperforated width. ** This dimension represents the length of any 100 consecutive perforation intervals

Figure 45

Perforation Type and ANSI Number

BH-1866

(PH22.93)BH-1870

(PH22.34)KS-1866

(PH22.139)KS-1870

(PH22.36)Tolerance

+/-

Dimensions Inches mm Inches mm Inches mm Inches mm Inches mm

A* 1.377 34.975 1.377 34.975 1.377 34.975 1.377 34.975 0.001 0.025

B 0.1866 4.74 0.1870 4.75 0.1866 4.740 0.1870 4.750 0.0005 0.013

E 0.079 2.01 0.079 2.01 0.079 2.01 0.079 2.01 0.002 0.05

F 0.999 25.37 0.999 25.37 0.999 25.37 0.999 25.37 0.002 0.05

G (max) 0.001 0.03 0.001 0.03 0.001 0.03 0.001 0.03 - -

L** 18.66 474.00 18.70 474.98 18.66 474.00 18.70 474.98 0.015 0.38




WEDNESDAY, JULY 31

Perforation Types

35 mm and 65 mm End Use

1. BH- 1870-35 mm Bell-Howell negative perforations with a pitch measurement of 0.1870" (long pitch), ANSI PH22.93-1980

2. BH-1866-35 mm Bell-Howell negative perforations with a pitch measurement of 0.1866" (short pitch), ANSI PH22.93-1980

3. KS-1870-35 mm and 65 mm Kodak Standard Positive perforations with a pitch measurement of 0.l870" (long pitch), ANSI PH22.139- 1980; PH22.145-1981

4. KS-1866-35 mm and 65 mm Kodak Standard Positive perforations with a pitch measurement of 0.1866" (short pitch), ANSI PH22.139-1980; PH22.145-1981

5. DH-1870-35mm Dubray-Howell perforations with a pitch measurement of 0.1870" (long pitch), ANSI PH22.102-1980

6. CS-1870-35 mm CinemaScope perforations with a pitch measurement of 0.1870" (long pitch), ANSI PH22.102-1980

7. KS-1870-70 mm film perforated 65 mm Kodak Standard Positive perforations with a pitch measurement of 0.1870" (long pitch), ANSI PH22.119-1981

16 mm End Use

8. 2R-2994-16 mm film perforated two edges with a perforation pitch of 0.2994" (short pitch), ANSI PH22.110-1980

9. 2R-3000-16 mm film perforated two edges with a perforation pitch of 0.3000" (long pitch), ANSI PH22.110-1980

10. IR-2994-Same as No. 8 except perforated one edge, ANSI PH22.109-1980

11. 3R-2994-35mm film perforated 16 mm with perforation pitch of 0.2994" (short pitch), ANSI PH22.171-1980

12. IR-3000-Same as No. 11 except with a perforation pitch of 0.3000" (long pitch), ANSI PH22.171-1980

13. 3R-3000-Same as No.11 except with a perforation pitch of 0.3000" (long pitch) ANSI PH22.171-1980

Optimum Pitch for Printing

Confinuous printers used for motion-picture film are designed so that the original film and the print raw stock are in contact (emulsion-to-emulsion) with each other as they pass around the printing sprocket, with the raw stock on the outside. To prevent slippage between the two films during printing (which would produce an unsharp or unsteady image on the screen), the original film must be slightly shorter in pitch than the print stock. In most continuous printers, the diameter of the printing sprocket, Figure 46, is such that the pitch of the original must be 0.2 to 0.4 percent (theoretically, 0.3 percent) shorter than that of the print stock. With nitrate film and early safety film, this condition was achieved by natural shrinkage of the original during processing and early aging. However, the substantially lower shrinkage of present safety films makes such a natural adjustment impossible; therefore, film used as printing originals is now manufactured with the pitch slightly shorter than the pitch of the print film. For 35 mm film, the pitch dimensions are


Page 1 of 3KODAK: Perforation Types


0.1870 inch (4.750 mm) on print film and 0.1866 inch (4.740 mm) on original film; for 16 mm film, they are 0.3000 inch (7.620 mm) on print film, 0.2994 inch (7.605 mm) on original film. For intermediate and print films used to make super 8 prints, the pitch dimensions are 0.1667 inch (4.234 mm) on print film, 0.1664 inch (4.227 mm) on intermediate film. This difference in pitch accounts for about 0.2 percent of the theoretical 0.3 percent; processing and aging shrinkage of the original film before printing usually provides the balance. See the first perforation type reference for additional information.

Projection Print Aspect Ratios

The aspect ratio is the relationship between the width and height of an image. While the image dimensions may vary in size according to projection requirements, the aspect ratio should comply with the cinematographic intent. The industry standard for theatrical motion pictures remained a constant 1.37:1 between the introduction of sound and the introduction of CinemaScope in 1953 when wide screen presentations were developed. While the original stereophonic (four -track magnetic) CinemaScope presentation had an aspect ratio of 2.55: 1, the flat, or nonanamorphic systems, designed to simulate wide screen images, provided several aspect ratios from 1.66:1 all the way up to and including 2:1. During this uncertain period, release prints were often printed with wider frame lines to emphasize that increased ratios were intended. During printing, the frame lines could be varied by printing the lines in to cover some of the original film image. At the same time, television's demands for feature films increased. However, because the typical television display provides a fixed ratio of 1.33:1, many of the films shown on television, after adjustment to fill the video screen height, lost a substantial part of the image at the edges. See Figure 47. Several approaches to rectifying this incompatibility were tried with various levels of success until the industry came to the current "consensus" that 1.85:1 would be the "normal" theatrical projection ratio but that the print would have an image of greater height so that it could fill a television screen without creating

Figure 46A printing sprocket

Figure 47Potential image lossed when changing aspect ratios



borders. Today, the usual procedure when filming productions for theatrical release and eventual TV showing is to "matte" the camera viewfinder to clearly indicate 1:85:1 and to keep all pertinent action within this area. Nevertheless, the entire 1.37:1 frame is exposed. The cinematographer must make certain no scene rigging, mike books, cables, or lighls are included in the expanded area. Subsequent release prints, therefore, contain a sufficient frame height to provide normal telecine transmission. In the theater, the projectionist must use a 1:85:1 aperture plate and exercise some judgment in adjusting the projector framing. This can be done conveniently during the showing of the titles.




WEDNESDAY, JULY 31

Film Identification

l Unprocessed Film l How to Read a Film Can Label l Processed Film l Know Your Films

¡ Test Exposures ¡ To Provide a Reference Point ¡ For Locations with Unfamiliar Lighting ¡ To Establish a Reference with You and Your Laboratory ¡ To Evaluate Specific End-Use Appearance ¡ To Determine the "Look" of the Finished Job ¡ To Check Specific Color Reproduction



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WEDNESDAY, JULY 31

Unprocessed Film

The eleven-digit code on the label in Figure 49 (5247-123-4567) identifies the film type (5247), the emulsion batch number (123), and the number of the roll (4567) from which this strip of Eastman Color Negative Film was cut. The emulsion batch number and roll number also appear on the tape sealing the can.

The Film Identification code (ECN 718 in this case) gives the emulsion type (ECN or Eastman Color Negative Film) and film specification number (718), a code describing width, perforation type and format, winding, and type of core, spool, or magazine.

The film width, perforation pitch, and emulsion position and winding type are identified on the label.

The film-strip reference number identifies the location of a particular strip of film cut from the master roll. This number (1 through 38 for 35 mm and 1 through 83 for 16 mm) appears on a sticker affixed to most cans holding 400 or more feet of film. Figure 48 shows such a sticker.

Figure 48

How to read a film can label


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Processed Film

The film strip reference number affixed to the can of raw stock film also appears as a latent image on the film itself. It is visible on the processed film between "Eastman" and "SAFETY FILM" on the edge print.

On 35 mm films having multiple -row perforations (used only by processing laboratories to print multiple copies of a film simultaneously), a lowercase letter or letters (a, b, c, etc) appear between "SAFETY" and "FILM" to identify the perforation format of the parent strip and the location of the sub strip within it.

The combinations of manufacturer's code (an uppercase letter for 35 mm or a trailer-end marking for 16 mm), film base data, and edge-print medium (ink or latent image) are helpful in identifying processed film. If a film data sheet carries a "Film Identification" heading, the uppercase letter of the manufacturer's code will be listed.

Film Sizes

Figure 49

Page 2 of 3KODAK: Unprocessed Film


WEDNESDAY, JULY 31

Know Your Films

Design, manufacture, actual shooting, projection, and storage conditions all influence film performance and selection. First we'll discuss why an on-site test is a good idea. Suppose your test shows that the film stock being considered produces unattractive results under the lights you plan to use to illuminate a few scenes. Will a filter correct the situation? Can you change the lighting? Will another film stock work better for those scenes?

Our second topic, filtration, covers the wide range of uses for filters to fill the needs of your unique circumstances.

The third section covers the process by which the sound you recorded is combined with your images in the final print.

The last two sections explain how to care for the finished films you have carefully created.

Test Exposures

Every production presents a unique set of conditions and demands. A full understanding of the job at hand and careful evaluation of the information in the data sheets should give the filmmaker a good idea of how a chosen film stock will respond to most filming situations. Testing reduces any remaining uncertainties and establishes the reaction of a particular film to a unique situation. Tle variations that make test exposures worthwhile and the technique of interpreting such exposures are the subjects of this section. Testing is one aspect of professional work too often overlooked in practice. When seeking the best possible results, filmmakers should run tests to provide reference points during production and to confirm choices based on previous experience and data sheet information.

Here, listed in the order of the time they may occur, are the principle causes of real or apparent changes in speed in all films, and contrast and color balance in color films. Failure to understand these causes can lead to misunderstanding or misinterpretation of photographic results:

l Slight manufacturing variations among different emulsion batches l Adverse storage conditions before exposure l Scene illumination of incorrect or mixed color quality l Differences in film sensitivity with changes in illumination level and

exposure time l Variations in equipment (lenses, shutters, exposure meters, etc) l Adverse storage conditions between film exposure and processing l Nonstandard processing conditions l Nonstandard viewing conditions l Differences in personal judgment

All except the first are beyond the scope of manufacturing control and cannot be predicted accurately from the data sheets. Furthermore, the variations encountered in practical use are apt to be a great deal larger


Page 1 of 3KODAK: Know Your Films


than those permitted by manufacturing tolerances. These are the basic reasons why you should make a test exposure whenever speed and color-balance are important. Test exposures are necessary for reversal materials that will be projected directly after processing more so than for negative or printed reversal materials because density and color-balance adjustments cannot be made during printing.

Most professionals realize the perishable nature of sensitized materials and are careful to avoid subjecting films (especially color) to extreme heat and humidity, either before or after exposure. The other factors listed are equally important, however, even if not equally familiar. None should ever be overlooked when choosing a film or attempting to explain an unexpected result.

Two or more causes of variation may influence results at the same time. Often the effects are additive, and minor single variations will, when combined, produce noticeable results unless proper compensation is made in advance. Only a test exposure under the practical conditions of use will furnish this information.

To Provide a Reference Point

A speed variation of 1/3 stop, and sometimes more, usually passes unnoticed when black-and-white film is projected. In a color film, where the performance of each emulsion layer is evaluated in terms of the other two, a much smaller variation in the relative speed of any one layer is evident to the user. Coating thickness is a manufacturing variable that provides an excellent illustration of the technical accuracy maintained in making color films. Tests have shown that the thickness of each emulsion layer must be controlled within 4 or 5 percent; any larger variation would by itself use up the entire color-balance tolerance available.

Since a typical color emulsion is only 3 ten thousandths of an inch thick, so only 15 millionths of an inch variation is allowable. And this kind of accuracy is maintained in making successive coatings on a thin, flexible base in the dark!

Every effort is made to achieve the greatest possible uniformity in the manufacture of Kodak films, but within such close tolerances minor variations are unavoidable. Of course, variations are smallest among films of the same emulsion number. In any case, test data obtained under actual production conditions is recommended to supplement the manufacturer's data.

At Kodak, the standardization of manufacturing operations is supplemented by an extensive testing and quality-control program. Only film produced within narrow tolerances of the production aim point is shipped from the manufacturing plant.

The actual sensitometric tolerances tested include speed, fog, contrast, color-contrast match, and maximum density. Production tests are made at normal room temperature with illuminants equivalent in color quality to tungsten (3200 or 3400 K) lamps for tungsten films and to average sunlight plus skylight (5500 K) for daylight films. They are exposed at times considered representative of the major applications for the films. In all cases, films are processed in accordance with process specifications. Physical characteristics such as curl, perforation pitch,



weave, tensile strength, freedom from scratches, etc., are also carefully controlled.

With Eastman and Kodak EKTACHROME Films, the permitted color-balance variations, tested under normal recommended use, fall approximately within the range correctable by a CC10 filter in the camera exposure. In the case of negative films, normal color-balance variations fall within a range for which adjustment can easily be made in the printing process.

The careful cinematographer should make practical picture tests on new film batches with the exposure and filtration to be used for the rest of the production. These tests will help to determine if any additional filtration and exposure adjustments are needed.

For Locations with Unfamiliar Lighting

Filmmakers are well aware that color films are balanced in manufacture for exposure to light of a certain color quality. Color negative film offers considerable latitude because some adjustments for color balance you can make during printing. Even reversal materials that will be printed offer some latitude because of the printing step. However, when a reversal material isn't going to be printed, you must make compensation if the light source differs in color quality from that for which the film is balanced. Even the "correct" light may be changed appreciably in color quality as it passes from source to subject to film. Discolored or dirty reflectors and camera lenses with a color tint can change color quality. Furthermore, the color quality of tungsten and fluorescent lamps can change with age and voltage fluctuations. Lighting from mixed sources will also change color renderings.




WEDNESDAY, JULY 31

Film Identification

To Establish a Reference with You and Your Laboratory

Different laboratories can produce noticeable variations in image quality and effective film speed, and from time to time variations can be noted at a single laboratory. Typical processing can result in speed variations of plus or minus 1/2-stop and color-balance variations on the order of +/-CC10 filter. Tests processed by your chosen laboratory serve as a base in all future discussions with the laboratory.

To Evaluate Specific End-Use Appearance

The conditions under which film is viewed have a marked effect on the apparent color quality of the picture. For critical applications, test film should be projected and evaluated under the specific conditions in which it will be used. The locations of the projector, the viewer, and the screen can affect the image quality dramatically.

To Determine the "Look" of the Finished Job

Because the viewers' reactions to a projected image involve their psychological responses, a projected image can never be "perfect" in any simple sense.

Like all photographic and electronic imaging systems, Kodak color films exhibit small color differences between the image and the subject itself when they are critically compared. Usually these differences are insignificant, but cinematographers have to judge whether the "look" of the film is consistent with their intentions and with the nature of the subject.

Since the manufacturer's evaluation of color balance is determined from picture tests judged by a number of observers, it is obvious that an individual cinematographer, producer, or laboratory may prefer a color balance different from one judged desirable by the manufacturer.

Because the manufacturer can never judge color balance appropriately for all tastes and all extremes of working conditions, critical work should be preceded by tests made as closely as possible to the conditions of final use, if possible, on the actual subject. You should always make the test on film of the same emulsion number as that to be used for the final exposure and kept under similar conditions before and after exposure. The exposure time, light source, and processing conditions should also be identical with those planned for the final work.

To Check Specific Color Reproduction

With only three dyes, color films are, able to produce a pleasing rendering of most colors. Occasionally, though, some colors present special difficulties in accurate reproduction, even though the film has been manufactured, stored, exposed, and processed correctly. Fortunately, the conditions that produce these effects are not common.




Since a large majority of all photographs include people, the reproduction of flesh tones is a primary consideration in the design of a color film. Also important are the reproduction of neutrals (whites, grays, and blacks) and the reproduction of common "memory" colors, such as blue sky, green grass, etc. Because films are designed to reproduce these colors properly under a variety of conditions, some other colors -such as shades of chartreuse, lime, pink, and orange-may reproduce less well. (It is possible to design a film that would improve the reproduction of these other colors, but only at the expense of generally more important flesh tones, sky, grass, etc.) More noticeable difficulties can be encountered because color films do not have exactly the same color sensitivities as the human eye. For most subjects, the three light-sensitive layers of the film do not have to "see" the subject exactly the same way the human eye does. In most cases, the differences are scarcely noticeable.

Sometimes, though, the differences between film sensitivity and visual sensitivity produce unwelcome results. Since color films are sensitive to ultraviolet radiation, a substance reflecting ultraviolet energy will reproduce bluer on film than it looks to the eye. If it is blue to begin with, this effect is of little or no consequence. With other colors, however, the additional blueness may neutralize the original color or even make it appear blue. Neutral and near-neutral colors are more apt to be affected by such a shift, because their saturation is low. For example, a black tuxedo made of synthetic material may appear blue. An ultraviolet absorbing filter, such as a Kodak WRATTEN Gelatin Filter No. 2B, over the lens or over the light source when practical can reduce this effect.

Closely related is the effect of ultraviolet fluorescence. Some fabrics absorb ultraviolet radiation and remit it in the near-blue (shortest wavelength) portion of the visible spectrum. Since the eye is not very sensitive in this part of the spectrum, the effect may not be readily apparent until a photograph of the subject is viewed. An analogous visual effect is created by black light which makes special paints, some fabrics, etc, glow in the dark.

Under an ultraviolet lamp, any fabric containing brighteners will fluoresce, but many white fabrics contain brighteners introduced during manufacture or laundering to give them a whiter appearance. Examination of any suspect fabrics under an ultraviolet source will generally indicate whether there will be a fluorescence problem. In this case, a filter over the lens does not help; however, an ultraviolet absorber over the light source may prove helpful. A photographic test is the best way to determine whether problems with reproduction in the ultraviolet range should be anticipated.

Perhaps most troublesome are the color reproduction problems sometimes called anomalous reflectance. They arise from high reflectance at the far red and infrared end of the spectrum, where the eye has little or no sensitivity. The heavenly blue moming glory and ageratum flowers are examples of colors occurring in nature that reproduce poorly because color films are much more sensitive to the far red than the eye. Among artificial materials, some classes of organic dye are notable examples of high reflectance in the far red. These dyes are currently very popular with fabric manufacturers because they are relatively inexpensive and work well with synthetic materials. While the high reflectance of these dyes in the far red and infrared can be found in all colors, its effect is most noticeable in medium to dark green fabrics,



where the photographic effect of the far red reflectance is to neutralize the green, making it appear browner.

You can identify high reflectance at the far end of the spectrum can be identified by use of a deep red filter such as a Kodak WRATTEN Gelatin Filter No. 70. If the materials are examined under a tungsten light, a green natural-fiber material will appear black, whereas a synthetic material with high reflectance in the far red will appear much lighter. Because the judgment is quantitative, a sample of a green fabric known to reproduce well should be compared with the test fabric under the filter. If the test fabric appears distinctly light in a side-by-side comparison through the No. 70 filter, you should expect a reproduction problern. Even then, confirmation by means of a photographic test under actual working conditions is advisable if circumstances permit.




KODAK

Gives You

The Edge

That Counts.

16mm

EASTMAN 16 mm KEYKODE NumbersUSERS’ GUIDE

Film Identification CodeLetter which identifies film type:

Strip Number

Current Films

D. . . 7234 Q. . . 7277E. . . 7222 R. . . 7289H. . . 7231 S. . . 7272I . . . 7246 U. . . 7279K. . . 7245 V. . . 7244L. . . 7293 Y. . . 7620M. . . 7248 Z. . . 7274

Discontinued Films

A. . . 7243 O . . . 7249C. . . 7297 T . . . 7298J. . . 7296 W. . . 7287N. . . 7292

EASTMAN KEYKODE NumbersKodak's machine-readable key numbers.Includes the 10-digit key number,manufacturer identification code, filmtype, and offset in perforations.(barcode detail next page)

Zero-Frame ReferenceMarkDot which identifies theframe directly below as thezero-frame specified by boththe human-readable keynumber and the machine-readable bar code.

ManufacturerIdentification Code(Below the Zero-FrameReference Mark) Letterwhich identifies filmmanufacturer. K=EastmanKodak Company.

Key Number:Prefix — Six digits that identify

film roll.

Count — Four digits that incrementevery six inches(20 perforations).

Tails Base Up

EASTMAN KEYKODE Numbers Information

Encoded in USS-128Barcode

Start Character is toward head of film

Manufacturer’s Information

Repeats every two feet (80 perforations).

Density PatchRepeats every ten feet(400 perforations).

Matching Check SymbolsFour randomly selected andplaced symbols designed as anextra matching check.

To Use: After matching keynumber and checking picture,verify that the same symbols arelocated in the same position onboth the workprint and thenegative.

Heads

KODAK

Gives You

The Edge

That Counts.

35mm

EASTMAN 35 mm KEYKODE Numbers USERS’ GUIDE

EASTMAN KEYKODE NumbersKodak's machine-readable keynumbers. Includes the 10-digit keynumber, manufacturer identificationcode, film type, and offset inperforations.(barcode detail next page)

Zero-Frame Reference MarkDot which identifies the framedirectly above as the zero-framespecified by both the human-readable key number and themachine-readable bar code.

ManufacturerIdentification CodeLetter which identifies filmmanufacturer. K=EastmanKodak Company.

Key Number:Count — Four digits thatincrement once per foot(64 perforations).

Prefix — Six digits that identifyfilm roll.

Base Up

Heads


Strip Number

Current Films

D. . . 5234 R. . . 5289E. . . 5222 S. . . 5272H. . . 5231 T. . . 5298 I . . . 5246 U. . . 5279K. . . 5245 V. . . 5244L. . . 5293 2244M. . . 5248 X. . . SFX 200TQ. . . 5277 Y. . . 5620

Z. . . 5274

Discontinued Films

A. . . 5243 J . . . 5296B. . . 5247 O . . . 5249C. . . 5297 P . . . 5600F. . . 5295 W. . . 5287G. . . 5294

Matching Check SymbolsTwo randomly selected andplaced symbols designed as anextra matching check.

To Use: After matching keynumbers and picture, verify thatthe same symbols are located inthe same position on both theworkprint and the negative.

Tails


EASTMAN KEYKODE Numbers Information

Encoded in USS-128 Barcode

Mid-Foot Key NumberPositioned halfway (+32 perforations) betweeneach main key and Keykode number, these mid-foot numbers identify short scenes that may notinclude a main key or Keykode number. Mid-footkey numbers are printed in smaller type todistinguish them from the main key numbers.

Frame-Index MarkerA hyphen every fourperforations helps locate theframe lines for dark scenes.

To Use: Locate one frameline. Determine its offsetfrom index marker (0, +1, +2,or +3 perforations). Use thisoffset for frame-linereference.Note: The frame-indexmarker is not printed whenit interferes with any otheredgeprint information.

Note: The solid squares alsoserve as density patches.

KODAK

Gives You

The Edge

That Counts.

65mm

EASTMAN KEYKODE NumbersKodak's machine-readable key numbers.Includes the 10-digit key number,manufacturer identification code, film type,and offset in perforations.(barcode detail next page)

Zero-Frame Reference MarkDot which identifies the framedirectly above as the zero-framespecified by both the human-readable key number and themachine-readable bar code.

Manufacturer Identification CodeLetter which identifies film manufacturer.K= Eastman Kodak Company.


Key NumberCount — Four digits that increment

every 120 perforations.

Prefix — Six digits that identify film roll.

Discontinued Films

A. . . 5243 J . . . 5296B. . . 5247 W. . . 5287C. . . 5297

Current Films

I . . . 5246 R. . . 5289K. . . 5245 T. . . 5298L. . . 5293 U. . . 5279M. . . 5248 V. . . 5244Q. . . 5277 Z. . . 5274


Heads Base Up

EASTMAN 65 mm KEYKODE NumbersUSERS’ GUIDE

This edgeprint format pertains to all Eastman 65mm negative and intermediate films.

EASTMAN KODAK Numbers Information

Encoded in USS - 128 Barcode

Matching Check SymbolsTwo randomly selected symbols for additionalmatching checks.

To Use: After matching key numbers andchecking picture, verify that same symbols arelocated in same position on both the workprintand the negative. Check symbols are anotheraid in matching very short scenes. The solidsquares also serve as density patches toevaluate edgeprint exposure.

One-third Key NumberThe key number +40, with bar codeand frame-reference dot, is offset 40perforations from the main key number.Use to identify short scenes which maynot include the main key number.

Two-thirds Key NumberLike the one-third key number,but +80 perforations followingthe main key number.

Frame-Reference MarkersA Dash, Key and Plus are printed atregular intervals to help locate framelines, especially for scenes shot inlow light.

– Dash: Frame reference mark for5- and 10-perf formats.

Key: Frame reference mark for8-perf format.

+ Plus: Frame reference mark for15-perf format.(Every third dash is a plus)

To Use: Locate one frame line andnearest reference marker for thegiven film format. Count the numberof perforations between the frameline and the marker. Use this perfoffset to identify the location offrame lines throughout the scene.

Note: Frame-reference markers arenot printed when they interfere withother edgeprint information.

Tails

ImprovedEdgeprintFormat forKODAK65mm Film

Interval between main Keykode numbers increased from80- to 120-perforations

Facilitates the development of software programs for accurateelectronic editing in all 65mm formats.

Two intermediate Keykode numbers offset 40- and 80-perforations from the main Keykode number

An aid in matching short scenes which may not include the mainkey number.

Larger (full-size) human-readable intermediate key numbersEasier to read on original and intermediate films. More legibleon 35mm printdown workprint. Along with +40 and +80 perfdesignators, the two alpha-characters preceding the keynumber are half size to further indicate these are intermediatekey numbers.

Frame-reference marker (key) added for 8-perf formatA new reference symbol for quickly locating the frame lines ofdark scenes shot in the 8-perf format. (An addition to the dashand plus symbols currently used to reference frame lines on5-, 10- and 15- perf formats.)

New manufacturer identification code-22Allows readers and software to automatically recognize thenew edgeprint format and accurately record Kodak Keykodenumbers from the new and previous formats, even whenintercut. Note: The identification code was 02 for the previous65mm format.

New printer number sequence -91 and -92Printer numbers (first two digits of the key number) are 91 or92. Printer numbers for previous Kodak 65mm films were 01or 02. On a negative cut list, the different numbers quicklyidentify the edgeprint format of the film.

Strip number added to the manufacturer's informationProvides further identification for any roll of 65mm film.

WEDNESDAY, JULY 31

Filtration

l Filters Useful with All Camera Films ¡ Polarizing Filters ¡ Neutral Density Filters ¡ Filters for Black-and-White Films ¡ Correction Filters ¡ Contrast Filters ¡ Haze Filters

l Filters for Color Films l Selecting Filters for Correcting Color Temperature l Light Source Conversion with Filters l Light Balancing Filters l Conversion Filters l Limits to Color Temperature Measurement l Ultraviolet-Absorbing and Haze-Cutting Filters l Color Compensating Filters for Color Correction

¡ Combining Color Compensating Filters ¡ Exposure Allowance for Filters ¡ Filters for Color Printing

White light is the sum of all the colors of the rainbow; black is the absence of all these colors. For practical purposes, we can consider white light as composed of equal amounts of three primary light colors-red, green, and blue. For example, if green and red are subtracted, we see blue. We, see many more colors in nature than these three because absorption and reflection of the primaries are rarely complete.

Our perception of a color is influenced by the surrounding colors and brightness level, the surface gloss of an object, and any personal defects in our color vision. Different films also see colors differently due to differences in spectral sensitivity. Filtration used with black-and-white films can control the shades of gray to obtain a technically correct rendition or to exaggerate or suppress the tonal differences for visibility, emphasis, or other effects. Filtration with color films can change the color quality of the light source to produce proper color rendition or to create special effects.

Colors as Seen in White Light

Colors of Light Absorbed

Red Blue and green

Blue Red and green

Green Red and blue

Yellow (red-green) Blue

Magenta (red-blue) Green

Cyan (blue-green) Red

Black Red, green, and blue

White None

GrayEqual portions of red, green, and blue


Page 1 of 2KODAK: Filtration

31/07/2002http://www.kodak.com/US/en/motion/students/handbook/filtration.jhtml

Filters always subtract some of the light reflected from a scene before it reaches the film plane in the camera. A red filter then is not "red" but rather a filter that absorbs blue and green. Similarly, a yellow filter is one that absorbs blue light. A yellow sunflower absorbs blue light and reflects the other parts of white light-red and green, which we see as yellow (lack of blue).


Page 2 of 2KODAK: Filtration

31/07/2002http://www.kodak.com/US/en/motion/students/handbook/filtration.jhtml

WEDNESDAY, JULY 31

Filters Useful with All Camera Films

Polarizing Filters

Polarizing filters (also called polarizing screens) are used to subdue reflections from surfaces such as glass, water, and polished wood, and for controlling the brightness of the sky. By reducing glare, polarizing filters also increase color saturation. Using a polarizing filter to control the brightness of the sky has several advantages over color filters: (1) The color rendering of foreground objects is not altered. (2) It is easy to determine the effect produced by the polarizing filter by checking the appearance of the image in the viewfinder (for cameras equipped with reflex-type viewfinders), or by looking through the filter when it is held at the same angle as used on the camera. (3) Other filters can be used with a polarizing filter to control the color rendering of objects in the foreground, while the polarizer independently controls the brightness of the sky.

The amount of polarized light from a particular area of the sky varies according to the position of the area with respect to the sun, the maximum occurring at an angle of 90º from the sun. Panning the camera, therefore, should be avoided with a polarizing because the sky will become darker or lighter as the camera position changes.

The sky may appear lighter than you would expect for these reasons:

l A misty sky does not photograph as dark as a clear blue sky. You can't darken an overcast sky by using a polarizing filter.

l The sky is frequently almost white at the horizon and shades to a more intense blue at the zenith. Therefore, the effect of the filter at the horizon is small, but it becomes greater as you aim the camera upward.

l The sky near the sun is less blue than the surrounding sky and, therefore, is less affected by a filter.

When you begin making exposures with a polarizing filter, be sure to remember that this filter has a minimum filter factor of 2.5 (increase exposure by 1 1/3 stops). This factor applies regardless of how the polarizing screen is rotated. In addition to this exposure increase, you must make any exposure increases required by the nature of the lighting. For example, for the dark-sky effect, the scene must be sidelighted or toplighted, so it will be necessary to add approximately 1/2-stop exposure to the 1 1/3- stop increase required by the polarizing filter factor.

Give an additional 1/2-stop exposure when you use a polarizing filter to eliminate reflections from subjects; reflections often make objects look brighter than they really are. See Figure 50.


Page 1 of 4KODAK: Filters Useful with All Camera Films

31/07/2002http://www.kodak.com/US/en/motion/students/handbook/filtration1.jhtml

Neutral Density Filters

Neutral density filters, such as the Kodak WRATTEN Neutral Density Filter No. 96, reduce the intensity of light reaching the film without affecting the tonal rendition of colors in the scene. Neutral density filters make it possible to film in bright sunlight using high-speed films without having to use very small lens openings. In black-and-white motion -picture photography, Kodak WRATTEN Gelatin Filters No. 03N5 and 8N5 permit the use of a larger lens opening for depth-of-field reduction. These filters combine a neutral density of 0.5 with the blue and ultraviolet correction capability of WRATTEN Gelatin Filters No. 3 and No. 8, respectively. In color motion picture photography, you can use combination filters, such as Kodak WRATTEN Gelatin Filters No. 85BN3 and 85BN6, to convert the color temperature from 5500 K (daylight) to 3200 K (professional tungsten lighting), and at the same time, obtain neutral densities of 0.3 and 0.6. Since a 0.3ND filter causes a one-stop reduction in exposure, these filters require, respectively, one and two stops of additional exposure.

Figure 50 A polarizer can eliminate reflectionson non-metallic surfaces.

Kodak WRATTEN Neutral Density Filter No. 96

Neutral Density

Percent Transmittance

Filter Factor

Increase in Exposure (Stops)

0.1 80 1 1/4 1/3

0.2 63 1 1/2 2/3

0.3 50 2 1

0.4 40 2 1/2 1 1/3

0.5 32 3 1 2/3

0.6 25 4 2

0.7 20 5 2 1/3

0.8 16 6 2 2/3

0.9 13 8 3

1.0 10 10 3 1/3

2.0 1 100 6 2/3

3.0 0.1 1,000 10

4.0 0.01 10,000 13 1/3



Filters for Black-and-White Films

Kodak WRATTEN Gelatin Filters are used with a wide range of black-and- white films for many purposes. They can emphasize clouds, reduce the brightness of blue sky and water, penetrate haze in distant landscapes, increase tonal contrast between colored objects, and produce special effects such as simulated night scenes.

The filters used in black-and-white work fall into three main types: (1) Correction filters change the color quality of the exposing light so that the film records all colors at approximately the relative brightness values seen by the eye. (2) Contrast filters change the relative brightness values so that two colors that would otherwise record as nearly the same shade of gray will have decidedly different brightness in the picture. (3) Haze filters reduce the effects of aerial haze.

Correction Filters

Most panchromatic emulsions have a high sensitivity to both ultraviolet and blue radiation. Because this sensitivity is dissimilar to the spectral sensitivity of the eye, blue or violet subjects are often overexposed and rendered too light on the final print. For example in location work, correction filters are often used to overcome an apparent lack of contrast between blue sky and white clouds. At the red end of the spectrum, certain higher speed panchromatic films possess a marked red sensitivity that, unless compensated for, tends to distort the rendering of red subject matter. Deliberate overcorrection is sometimes done to achieve special effects.

Foliage looks slightly darker than we expect when it is photographed on black-and-white film without a filter. By using a yellow or yellow-green filter to absorb some of the unwanted blue and red light, you can record foliage in its proper gray tone.

This may seem to imply a contradiction: If a filter subtracts light, there will be less density on the negative and the print will be darker, so how does the filter make foliage lighter? Actually, the filter darkens the rendering on the print of the color it absorbs, thus making the colors it transmits lighter by comparison.

This becomes apparent when the negative is correctly printed.

Contrast Filters

Used with black-and-white films contrast filters change the relative contrasts between two objects that would normally photograph as nearly the same shade of gray. The following guideline will help you choose contrast filters: A filter transmits its own color, making that color lighter in a black-and- white print. To make a color darker, use a filter that will absorb that color. If you use a No. 25 red filter, which transmits the red of the geranium blossoms and absorbs the green of the grass, the geraniums will be light and the grass dark in your print. Since you probably think of the flowers as being brighter than the grass, this print may look natural to you. But if you use a No. 58 green filter, which absorbs the red of the geraniums and transmits the green of the grass, you'll get the opposite result: dark flowers and light grass. You can also underexpose the film when using a contrast filter to simulate a night effect under daylight conditions; use orange and red filters, such as



Kodak WRATTEN Filter Nos. 23A, 25, 29, or 72B.

The color filter circle, Figure 51 , will help you decide what filters to use to lighten or darken the gray-tone rendering of most colors. The No. 58 filter is green, for example, which lightens the gray-tone rendering of green, yellow, and blue-green, and darkens the rendering of orange, magenta, and red. The filter factors given are often different for tungsten and for daylight because tungsten light contains relatively more red light while daylight contains more blue.

Haze Filters

The effects of haze can be reduced by filtering out some of the blue and ultraviolet lighy. Yellow filters, commonly used for haze peneration and darkening of the sky, are Kodak WRATTEN Filters No. 3, 8, 12, and 15, in order of increasing absorption. For further darkening of the sky and increased haze penetration, use filters ranging from light orange to deep red, such as filters No. 21, 23A, 25 and 29. These filters absorb varying degrees of blue light and green light.

Figure 51Note: If conditions require long time exposures, corrections for reciprocity effect in addition to the corrections for the filter factor may be necessary. * For a gray-tone rendering of colors approximating their visual brightness.




WEDNESDAY, JULY 31

Filters for Color Films

In exposing color films and in making prints and intermediates, there are a number of conditions under which you can obtain good color rendition through the use of correcting filters. Daylight and artificial light differ from one another in spectral quality and are individually subject to considerable variation. When the actual light is different from that specified for a particular film, correction filters can adjust the color quality of the illumination to that for which the film is balanced.

Data sheet tables are usually a reliable guide to the right filters for obtaining optimum color balance and are especially useful as a starting point from which to run tests. However, they cannot cover all such variables as high or low voltage, aging of lamps, or color contribution of diffusers. Color-temperature meters measuring the three primary colors provide an accurate method of determining the spectral-energy distribution of light sources as they relate to the sensitivities of the three layers in color films. Such meters as the Spectral-tricolor meter and the Minolta 3 color meter, while costly, provide the user an excellent means of finding the actual spectral distribution. Two-color meters (much less costly) show the balance between the red and blue light, and are adequate to indicate the spectral distribution of light sources having a continuous energy distribution across the spectrum (such as an incandescent light). They are not satisfactory for sources (such as fluorescent lights) having a skewed or discontinuous distribution.

Some meters give a choice of correcting the balance either wilh color balancing and conversion filters or with color compensating filters. In most instances, making the main correction with color compensating filters requires many filters, whole correcting with light balancing and conversion filters requires two at the most. Because the addition of many filters over a camera lens increase flare and decreases sharpness, color temperature (red- blue) correction is best made with light balancing and conversion filters and green-magenta adjustment is best made with color conipensating filters.

Selecting Filters for Correcting Color Temperature

The color quality of some illuminants can be expressed in terms of color temperature-a measure of the light irradiated by an idea-radiator, that is, a black body heated to incandescence. When the visual color of the illuminant is the same, or nearly the same, as that of the ideal radiator at a given temperature, the illuminant color is described in terms of the corresponding temperature of the ideal radiator, which is expressed in degrees Kelvin (K).

NOTE: Do not confuse sunlight with daylight. Sunlight is the light of the sun only. Daylight is a combination of sunlight plus skylight. The values given are approximate because many factors affect color temperature. Outdoors, the sun angle and the conditions of sky, clouds, haze, or dust particles will raise or lower the color temperature. Indoors, tungsten bulbs are affected by age (and blackening), voltage,type of reflectors and diffusers -all of which can influence the actual color temperature of the light. Usually, a change of 1 volt equals 10K. But this is true only


Page 1 of 2KODAK: Filters for Color Films


within a limited voltage range and does not always apply to booster voltage operation since certain bulbs will not exceed a certain color temperature regardless of the increase in voltage.

Color Temperature for Various Light Sources

Artificial Light

SourceDegrees Kelvin

Match Flame 1,700

Candle Flame 1,850

40-Watt Incandescent Tungsten Lamp 2,650





3200 K Tungsten Lamp 3,200

Molard "Brute" with Yellow Flame Carbons and YF-101 Filter (approx)

3,350

"C.P." (Color Photography) Studio Tungsten Lamp

3,350

Photoflood and Reflector Flood Lamp 3,400

Daylight Blue Photoflood Lamp 4,800

White Flame Carbon Arc Lamp 5,000

High-Intensity Sun Arc Lamp 5,500

Xenon Arc Lamp 6,420

DaylightSource Degrees Kelvin

Sunlight: Sunrise or Sunset 2,000

Sunlight: 1 Hour after Sunrise 3,500

Sunlight: Early Morning 4,300

Sunlight: Late Afternoon 4,300

Average Summer Sunlight at Noon (Washington, DC)

5,400

Direct Midsummer Sunlight 5,800

Overcast sky 6,000

Average Summer Sunlight (plus blue skylight)

6,500

Light Summer Shade 7,100

Average Summer Shade 8,000

Summer Skylight Will Vary from 9,500 to 30,000


Page 2 of 2KODAK: Filters for Color Films


WEDNESDAY, JULY 31

Light Source Conversion with Filters

To evaluate filter requirements for the conversion of light sources, it is helpful to use the reciprocal of the color temperature. The concept of expressing color temperature in reciprocal form is useful because a given sum of reciprocal units corresponds approximately to the same color difference for most visibly emitting sources (in the range from 1000 K to 10,000 K). The reciprocal color temperature is commonly multiplied by 1,000,000 to give numbers of convenient size. The values obtained by this operation have, in the past, been called micro -reciprocal degrees or "mireds."

Recently, the term reciprocal megakelvins (MK-1) has been used to replace mireds. The reciprocal color temperature expressed in reciprocal megakelvins has the same numerical value as with mireds, but the value is arrived at by first expressing the color temperature in megakelvins (1 MK = 1,000,000 K) and taking the reciprocal. For example, the reciprocal color temperature for a 6000 K source is

1/0.006 MK = 167 MK-1

Filters such as Kodak Light Balancing Filters and Kodak WRATTEN Photometric Filters modify the effective color temperature, hence the reciprocal color temperature, of any light source by a definite amount. Each filter can be given a visual shift value that is defined by the expression

where T1 is the color temperature of the light through the filter (both

values expressed in megakelvins). Remember that the concept of color temperature relates to the response of the visual system. To match the actual response of films as opposed to the response of the eye, some filters are designed empirically to fit existing photographic requirements. These filters may or may not provide a visual shift that relates to the measured photographic effect. This list give filters that provide the desired photographic result when used for the conversion indicated. The shift value given is a nominal value defined by the equation

and is not a measure of the visual shift that might actually be computed for the filter. A new concept termed photographic color temperature is being developed. If this method proves viable, reporting additional filter data in terms of photographic effect should provide greater assistance in the choice of appropriate filters for photography under a wide range of illuminants.

1,000,000 x1 Tk

1 T2

- 1 T1

1 T2

- 1 T1


Page 1 of 3KODAK: Light Source Conversion with Filters


The light source conversion nomograph shown in Figure 52 is designed to simplify the problem of selecting the proper conversion filter. The original light source, T 1, is listed in the left column and covers the

practical range of color temperatures from 2000 to 10,000 K. The right-hand column lists the color temperature of the light through the filter-that is, the converted source, T 2. The center column shows the scale of reciprocal megakelvin (MK -1) shift values. To find the shift value and consequently the filter required for a particular conversion, it is only necessary to place a straightedge on the points corresponding to the color temperature of the available source, T1, and the desired color

temperature of the filtered source, T2, respectively. The straightedge

crosses the center column and indicates the reciprocal megakelvin shift value of the required filter. The zero point on this column indicates that no filter is required, values above zero point (+) require yellowish filters, and those below the zero point (-) require bluish filters.

Filters can also be combined, the desired combination being calculated by adding the (MK- 1) shift values of the filters, with due regard to the sign. If you use more than one filter, remember that the illumination loss and flare due to reflection of the multiple surfaces may become considerable.

* Values in reciprocal megakelvins (MK -1) are equal numerically to values in "mireds."

Light Balancing Filters

Color motion picture films are balanced in manufacture for use either with tungsten light sources (3200 K, type B, or 3400 K, type A) or with illumination of daylight quality (5500 K). Kodak Light Balancing Filters are used over the camera lens to enable the photographer to make minor adjustments to the light reaching the film. If the required color-balance adjustment is small, a single bluish filter of the No.82 series, or a single yellowish filter of the No. 81 series, will be adequate. Kodak Light Balancing Filter No. 82 is intended, in effect, to raise color temperature by 100 K, the 82A by 200 K, the 82B by 300K, and the 82C by 400 K. Those of the No. 81 series (91, 81A, 81B, 81C 81D) are intended to reduce color temperature by 100 K steps. For greater color correction, combine two filters in the same series.

Conversion Filters

If still greater corrections in color are required, you can use light balancing filters and conversion filters. Use conversion filters over the camera lens to make significant changes in the color temperature of

Reciprocal Color Temperature (MK-1)for Color Temperatures from 2000K to 6900 K*

K 0 100 200 300 400 500 600 700 800 900

2000 500 476 455 435 417 400 385 370 357 345

3000 333 323 312 303 294 286 278 270 263 256

4000 250 244 238 233 227 222 217 213 208 204

5000 200 196 192 189 185 182 179 175 172 169

6000 167 164 161 159 156 154 152 149 147 145



illumination (e.g., daylight to artificial light).

Limits to Color Temperature Measurement

Color temperature refers only to the visual appearance of a light source and does not necessarily describe its photographic effect. Although some light sources emit strongly in the ultraviolet region of the spectrum, the color temperature of such a source does not measure this portion of the emission because the eye is not sensitive to radiation below 400 nm. Since a film is usually sensitive to ultraviolet radiation, a scene can record overly blue unless special corrective means are used to filter out the ultraviolet.

Also, color temperature does not take into account the spectral distribution of a light source. Unless the light source has a similar spectral distribution to that of a black body radiator (e.g. various types of tungsten- filament lamps), its effective color temperature alone may not be reliable as a means of selecting a suitable filter for adapting the source for color photography. Fluorescent lamps, for example, do not have the continuous, smooth spectral-distribution curve that is characteristic of a tungsten- filament source.

Although two different light sources may be described as having the same color temperature, the photographic results obtained with each may be quite different.




WEDNESDAY, JULY 31

Ultraviolet-Absorbing and Haze-Cutting Filters

Photographs of distant landscapes, mountain views, snow scenes, scenes over water, and sometimes aerial photographs in open shade made on color films balanced for daylight are frequently rendered with a bluish cast. This is caused by the scattering of ultraviolet radiation to which the film is more sensitive than the human eye. Kodak WRATTEN Filter No. 1A (skylight filter) absorbs ultraviolet light. By placing this filter over the lens, you can reduce the bluish cast and slightly penetrate the haze.

Kodak Light Balancing and Conversion Filters for Color Films

Kodak Light Balancing Filters

Filter Color

Filter Number

Exposure Increase in Stops*

To Obtain 3200 K from

To Obtain 3400 K from

Nominal Shift Value

(MK-1)*

Bluish

82C + 82C 82C + 82B 82C + 82A 82C + 82

82C 82B 82A 82

1 1/3 1 1/3

1 1

2/3 2/3 1/3 1/3

2490 K 2570 K 2650 K 2720 K 2800 K 2900 K 3000 K 3100 K

2610 K 2700 K 2780 K 2870 K 2950 K 3060 K 3180 K 3290 K

-89 -77 -65 -55 -45 -32 -21 -10

No Filter Necessary 3200 K 3400 K -

Yellowish

81 81A 81B 81C 81D 81EF

1/3 1/3 1/3 1/3 2/3 2/3

3300 K 3400 K 3500 K 3600 K 3700 K 3850 K

3510 K 3630 K 3740 K 3850 K 3970 K 4140 K

9 18 27 35 42 52

Conversion Filters

Filter Color

Filter Number


Conversion in Degrees K

Nominal Shift Value

(MK-1)*

Blue

80A 80B 80C 80D

2 1 2/3

1 1/3

3200 to 5500 3400 to 5500 3800 to 5500 4200 to 5500

-131 -112 -81 -56

Amber

85D 85

85N3 85N6 85N9 85B

85BN3 85BN6

1/3 2/3

1 2/3 2 2/3 3 2/3 2/3

1 2/3 2 2/3

5500 to 3800 5500 to 3400 5500 to 3400 5500 to 3400 5500 to 3400 5500 to 3200 5500 to 3200 5500 to 3200

81 112 112 112 112 131 131 131

*These values are approximate. For critical work, they should be checked by practical


Page 1 of 5KODAK: Ultraviolet-Absorbing and Haze-Cutting Filters


Color Compensating Filters for Color Correction

A color compensating (CC) filter controls light by attenuating principally one or two of the red, blue, or green parts of the spectrum. You can use, them singly or in combination to introduce almost any desired color correction. Use CC filters to make changes in the overall color balance of pictures made with color films, or to compensate for deficiencies in the spectral quality of the light to which color films must sometimes be exposed. Such corrections are often required, for example, in making color prints or in photography with unusual light sources. If the color balance of a test is not satisfactory, the extent of filtering required to correct it can be estimated by viewing the test print through color compensating filters.

Kodak Color Compensating Filters have excellent optical quality and are suitable for image-forming optical systems-over the camera lens, for example. However, because they are gelatin filters, they are very

test, especially if more than one filter is used.

The nomograph can be used to find the shift value for a particular conversion by placing a staightedge from an original source (T

1) to a second source (T

2). The shift value

can be read on the center line. Use of the nominal shift values for filters shown on the previous tables will allow choice of filters that approximate the necessary correction. Shift values are algebraically additive; filters can be combined to acheive the required shift.

Figure 52



susceptible to scratches and fingerprints, both of which can affect optical quality to a serious degree. Color compensating filters are available in several density values for each of the following colors: cyan, magenta, yellow, red, green, and blue.

The density of each color compensating filter is indicated by the numbers in the filter designation, and the color is indicated by the final letter. In a typical filter designation, CC20Y represents a "Color Compensating Filter with a density of 0.20 that is Yellow."

The densities of color compensating filters are measured at the wavelength of maximum absorbtion (i.e., the density of a yellow filter is given for blue light). That's the reason the term peak density is used in the table. The density values do not include the density of the gelatin on which the filter dye is coated, nor do they include the density of the glass in which a filter may be mounted.

The standardized density spacing of these filter series (5, 10, 20, 30, 40, 50 in each color) helps predict the photographic effects of filter combinations. The red, green, and blue filters each absorb two thirds of the visible spectrum; the cyan, magenta, and yellow filters each absorb one third of the spectrum. In the red, green, and blue series, each filter contains the same dyes in approximately the same amounts as the two corresponding yellow and magenta, yellow and cyan, or magenta and cyan filters.

Combining Color Compensating Filters

The determination of filter combinations can usually be simplified by thinking of all the filters in terms of the subtractive colors:

Red (absorbs blue and green) = yellow (absorbs blue) + magenta (absorbs green) Green (absorbs blue and red) = yellow (absorbs blue) + cyan (absorbs red) Blue (absorbs green and red) = magenta (absorbs green) + cyan (absorbs red)

The following method of calculation is recommended:

1. Convert the filters to their equivalents in the subtractive colors -cyan, magenta, and yellow-if they are not already of these colors. For example,

20R = 20M + 20Y.

2. Add like filters together. For example,

20M + 10M = 30M.

3. If the resulting filter combination contains all three subtractive colors, cancel out the neutral density by removing an equal amount of each. For example,

10C + 20M + 20Y = 10M + 10Y + 0.10ND (neutral density, which can be eliminated).



4. If the filter combination contains two different filters of equal density, substitute the equivalent single red, green, or blue filter. For example,

10M + 10C = 10B.

Exposure Allowance for Filters

You must make filters absorb light. You must increase exposure for this loss of light. The published exposure increases for Kodak Color Compensating Filters (see below) provide a rough guide to the exposure adjustments required for a single filter. To determine the exposure increase for two or more filters of different colors run practical tests using initially the sum of the suggested increases for the individual filters.

Filters for Color Printing

Motion picture printers used for printing color films are generally equipped with high-wattage lamps, making it necessary to insert a heat-absorbing glass to protect the mirrors and filters in the printer optical system from damage. Use a dichroic heat-reflecting glass or a heat-absorbing filter. The Heat Absorbing Filter No. 2043 (4 mm) now used in many laboratories is satisfactory. It is available from Kodak. An ultraviolet-absorbing filter may also be required, as specified on the data sheets.

Kodak Color Printing Filters, listed in the table below, are made on an acetate film base and are used singly or in combination for color correction of light sources in subtractive color printing. Color printing (CP) filters are similar to color compensating (CC) filters in that they control principally the red, green, or blue parts of the visible spectrum; unlike CC filters, CP filters cannot be used in the image-forming beam if optimum quality is desired.

Kodak Color Compensationg Filters

Peak Density

Yellow (Absorbs

Blue)


Magenta (Absorbs Green)


Cyan (Absorbs

Red)


0.025 0.05 0.10 0.20 0.30 0.40 0.50

CC025Y CC05Y** CC10Y** CC20Y** CC30Y CC40Y** CC50Y

- -

1/3 1/3 1/3 1/3 2/3

CC025M CC05M** CC10M** CC20M** CC30M CC40M** CC50M

- 1/3 1/3 1/3 2/3 2/3 2/3

CC025C CC05C** CC10C** CC20C** CC30C CC40C** CC50C

- 1/3 1/3 1/3 2/3 2/3 1

Peak Density

Red (Abosrbs Blue and Green)


Green (Absorbs Blue and

Red


Blue (Absorbs Red and Green)


0.025 0.05 0.10 0.20 0.30 0.40 0.50

CC025R CC05R** CC10R** CC20R** CC30R CC40R CC50R

- 1/3 1/3 1/3 2/3 2/3 1

CC05G CC10G CC20G CC30G CC40G CC50G

- 1/3 1/3 1/3 2/3 2/3 1

CC05B CC10B CC20B CC30B CC40B CC50B

> - 1/3 1/3 2/3 2/3 1

1 1/3* These values are approximate. For critical work, they should be checked by practical tests, especially if more than one filter is used. **Similar Kodak Color Printing Filters (Acetate) are available.



See Kodak Publication No. B-3, Handbook of Kodak Photographic Filters, for more technical information concerning the filters discussed in this section.

Kodak Color Printing FiltersCyan Magenta Red Yellow

CP05C CP10C CP20C CP40C

CP05M CP10M CP20M CP40M

CP05R CP10R CP20R CP40R

CP05Y CP10Y CP20Y CP40Y




WEDNESDAY, JULY 31

Motion Picture Sound Recording

l A Brief History of Sound l Magnetic and Photographic Sound

¡ Photographic Tracks ¡ Basics of Photographic Sound ¡ Photographic Sound-Track Reproduction



Page 1 of 1KODAK: Motion Picture Sound Recording

31/07/2002http://www.kodak.com/US/en/motion/students/handbook/recording.jhtml

WEDNESDAY, JULY 31

A Brief History of Sound

Sound was introduced to the movies in 1927 with Al Jolson's The Jazz Singer. In 1977, the motion picture industry celebrated the 50th anniversary of the talkies.

1920's

The very first sound was produced in the early 1900's from a phonograph disk running in mechanical synchronism with the picture at 33 1/3 RPM. Obvious synchronization problems requiring the constant attention of the projectionist led to a system which allowed the picture and sound track to be printed together on the same piece of film.

1930's

Two photographic-sound recording systems evolved-variable-density and variable-area. Variable-density meant that the density of the sound track varied in accordance with the audio signal. Variable-area meant that the width of the clear area of the track varied with the signal.

Also, there were several different types of variable-area tracks-the earliest unilateral, the improved bilateral and dual-bilateral and the special push-pull tracks. Because of the complexities of push-pull tracks, they were used for in-house operations, not released. Only on picture, the 1941 version of Walt Disney's Fantasia , was released with push-pull tracks, and then only as a special road show performance where Disney technicians had complete control.

1940's

The primary shortcoming of photographic sound tracks was (and still is) noise. Early in their use, schemes were devised for noise reduction. Over the years, many variations of both variable density and variable-area tracks were developed to increase their dynamic range. This need for greater sound level led to the abandonment of variable density in favor of the higher output variable -area recording.

The added realism of stereophonic sound challenged engineers. In the late 1930's, Bell Labs developed a stereo system with four variable -area tracks on 35 mm film and in 1941, Fantasia was released as the first commercial stereo release.

1950's

The 1950's brought wide-screen pictures-most using multiple magnetic tracks for stereo sound. The driving force was more realistic and exciting theater entertainment to counter the home TV threat to their business. In late 1952, a three-camera, three-projector, ultra-wide screen format was introduced. Its seven sound tracks were on a separate film run synchronously with the picture. In 1953, Fox released The Robe in CinemaScope,--a 2.35:1 wide screen picture from a standard 35 mm print with four magnetic tracks, three for wide-band audio and a narrow


Page 1 of 4KODAK: A Brief History of Sound

31/07/2002http://www.kodak.com/US/en/motion/students/handbook/recording1.jhtml

track for surround sound. Todd-AO, the company which invented 70 mm 6-track magnetic sound tracks, revolutionized the industry with its 70 mm release of Oklahoma in 1955. This double -width film not only gave the very best wide-screen picture, but its six magnetic-sound tracks produced stereo sound of superb quality. Many other wide-screen contenders offering improved quality or lower cost came and went-CinemaScope 55, MGM Camera 65, Cinemiracle, Technirama, and VistaVision.

1960's and 1970's

In the 1960's and early 1970,s, 70 mm 6-track magnetic sound and 35 mm CinemaScope fared the best. However, the laws of economics did catch up with CinemaScope. Ninety percent of these prints were released with no magnetic tracks, only a monaural optical track. Of the remaining 10 percent that had magnetic tracks for stereo, nearly all also had a 1/2 width optical sound track nudged in so that the print could be played in theaters without magnetic stereo capability. The reason was simple. The addition of magnetic stripes and recording four tracks on each print increased their cost from 50 to 75 percent. Also, superior magnetic sound required scrupulous and costly maintenance of the magnetic sound reproducers.

These cost pressures caused engineers to take a close look at optical sound. If they could substantially improve the frequency response and signal-to-noise ratio of an optical track, several tracks could be recorded in the space used for one. They could produce stereo sound without the added print costs of magnetic tracks.

In mid-1965, Ray Dolby from Oregon, then living and working in England, developed a noise reduction system for magnetic reduction in magnetic recording that was adopted immediately in the music industry. In 1972, Dolby noise reduction was introduced into motion-picture sound- recording, but for monaural sound, not stereo sound.

Dolby Laboratories, spurred by a Kodak employee, Ron Uhlig's success with 2-track, 2-channel stereo sound for 16 mm film, developed a 2 -track stereo variable-area system with complete compatibility. Theaters converted to decode Dolby tracks could enjoy the low noise, relatively wide-frequency range stereo reproduction and also get acceptable monaural sound when playing a standard Academy mono print.

Also, Dolby-encoded stereo prints would yield acceptable monaural reproduction on unconverted projectors on theaters not equipped for stereo. In 1974, two pictures were released with Dolby Stereo Variable -Area (SVA) tracks; in 1976, four pictures; and by 1978, 25 pictures. Over 900 theaters worldwide were equipped to reproduce Dolby-encoded SVA tracks by 1979.

At that time, it cost between $10,000 and $15,000 to add Dolby SVA to theaters already equipped to play stereo from 4-track CinemaScope or from 6-track 70 mm prints. For theaters only able to play monaural tracks, these costs increased to between $15,000 and $25,000. All for the attraction of Dolby Stereo on the marquee, but that's proved to be a substantial attraction to the many theaters who invested in Dolby.

Other contenders for this marketplace were Colortek, Todd-AO/Nuoptix, Universal with its Sensurround, 20th Century -Fox with their Fox Sound



360, and Pacific Theaters with their drive-in bilingual presentation of Star Wars .

1980's

Through it all, three formats have withstood the test of time:

l 35 mm Monophonic Photographic Sound Tracks or Academy Tracks-a standard format since 1927. These are bilateral or dual-bilateral variable- area tracks. The term Academy was coined because of standardization efforts made in the late 1930's by a group at the Academy of Motion Picture Arts and Sciences.

l 35 mm Stereophonic Photographic Sound Tracks with Dolby Noise Reduction-the most common 35 mm format today. Dolby calls them SVA or Stereo Variable -Area Tracks.

l 70 mm Magnetic Sound Tracks-a format used in specialized theaters who promote a wide-screen image and high-quality sound. The picture is shot on either 65 mm or 35 mm negative film and the final print is released on 70 mm print film. The only difference between 65 mm and 70 mm film is the added width of 2.5 mm outside the perforation area on each edge of 70 mm film for the magnetic stripes.

By the mid-1980's, considerable interest had developed in digital sound on motion picture film. This interest was spurred to no small degree by the availability to the consumer of compact audio discs. This digital recording medium is quickly supplanting tape and long-play phonograph records for home sound systems because of its virtually flawless audio quality.

1990's and Beyond

In 1990, Cinema Digital Sound (CDS) for film became a reality. The Cinema Digital Sound System was co -developed by Optical Radiation Corporation and the Motion Picture and Television Products Division of Eastman Kodak Company. CDS features six discrete channels of pure digital sound optically encoded on the print film. CDS debuted in 1990 at selected theaters featuring Dick Tracy in the 70 mm format in New York City and Los Angeles.

CDS provides filmmakers with a precise ability to control the direction and movement of sound to create a more compelling illusion of reality. Five discrete channels reproduce the full tonal and frequency ranges the human ear is capable of hearing. A separate sub-woofer channel reproduces the lowest bass tones.

CDS is designed to provide consistent audio quality for the life of the print. Wear and tear can reduce the audio quality of conventional 35 mm optical and 70 mm magnetic sound tracks. To provide this durability of the digital sound track, CDS features a sophisticated error collection system to ensure that every audience will hear opening night sound quality, even months later.



The separation of sound into six discrete channels ensures that audiences will not only hear all of the subtleties of dialogue, effects, and music, the way it is meant to be heard, but from the special location where it originated.

The ability to encode digital sound optically on film required a major technological breakthrough providing the key to affordability and reliability of CDS.

Theatres equipped with single channel surround speakers can easily retrofit for the dual channel surround of CDS. All it requires is installation of a digital decoder on the projector and a digital-to-analog processor in the projection booth equipment-rack. Some theaters may consider the option to upgrade speaker systems to realize the full potential that CDS offers.

CDS technology for 70 mm and 35 mm release prints is virtually the same. A decision was made to debut CDS in 70 mm format so the new audio system could be introduced in road show theaters.

Motion pictures can be released in CDS format by simply remixing the audio made for conventional prints to six discrete channels of digital optical sound.

Eventually recording and mixing techniques will evolve to take full advantage of CDS features. More original sound will be recorded and mixed digitally now that there is a way to release movies in digital sound format.

Figure 53




WEDNESDAY, JULY 31

Magnetic and Photographic Sound

Sound is recorded on a motion picture print in one of two ways, either magnetically on a metallic oxide strip coated on the film or photographically by an optically modulated light system.

A magnetic sound track consists of a strip of metallic oxide coated along the edge of a motion picture film. Sound is recorded on this stripe by running it past a magnetic recording head that selectively magnetizes the metallic particles in the coating. Since coating formulations have been developed that are not affected by the processing chemicals, they can be applied to the film before (prestripe) or after (poststripe) processing. Seventy-millimeter and some 35 mm prints may have multiple stripes for stereophonic sound and special sound effects.

A second, much narrower stripe of the same thickness and, usually the same material is coated near the edge of the film support that is used for the sound stripe (between the perforations and the nearest edge) on 16 mm and super 8. This stripe is normally not used for magnetic recording; it balances the film mechanically to keep it from telescoping or binding against the reel flanges during projection and rewinding.

A photographic sound track is a record of sound (voice, music, etc.) printed near the edge of a motion picture film. Photographic sound tracks are usually printed on the film at the same time as the photographic image. Thus, the two can also be duplicated simultaneously, unlike magnetic sound tracks which must be recorded on each print in a separate nonphotographic operation.

A film producer who wants photographic sound sends the rough-edited workprint, the original film, the script, and the final magnetic recording to a laboratory where conforming, editing, and addition of the sound track are accomplished. The original film, or a printing master with photographic sound track, is then printed for release.

Photographic sound prints can be made from original films with magnetic sound stripes or from original films and separate magnetic tracks. A photographic sound track will last the life of the film and cannot be easily damaged through cleaning or other maintenance of the film. There is also no danger of accidentally erasing the track. However, the reproduction fidelity of photographic sound tracks can be degraded by dust particles and scratches. Also, changes cannot be made in a photographic sound track after it has been printed on the film.

Magnetic tracks, on the other hand, are less susceptible to dust and dirt distortion and are degraded very little by scratches. The magnetic stripe offers other advantages. The additional height of the magnetic stripe raises the emulsion (image) off the base side of the next convolution of film on a reel, protecting the picture area from frictional damage, emulsion-to-base sticking, etc. The stripe may also have higher fidelity sound (greater frequency response and better signal-to-noise ratio).

Photographic Tracks


Page 1 of 4KODAK: Magnetic and Photographic Sound


A photographic sound-track negative consists of an exposed area whose width and area vary with the volume and frequency of sound recorded. The track looks like one or more narrow, jagged, black-and-white patterns along the edge of the film. For optimum quality on a variable-area sound track, the clear portions should be as transparent as possible, and the dark portions should have a density at wavelengths from 800 to 1000 mm between 1.0 and 1.8. Consequently, emulsions and processes that produce high contrast are generally used to record variable-area sound-track negatives.

Basics of Photographic Sound

The reproduction of sound requires that the sound waves be converted into electrical signals which are then recorded. The record can then be played back, generating electrical signals, which can be converted back to sound waves by the speakers. In photographic sound reproduction, the actual sound record on the print is a silver, dye, or dye-plus-silver image along the edge of the film.

Figures 54A, B, and C show the components which convert the photographic sound track into electrical sound signals. The light energy from the lamp is formed into a narrow beam by a lens and aperture. The beam is transmitted through the sound-track area of the film and then strikes a photocell.

Figure 54aSchematic of optical sound reproduction.

Figure 54b Figure 54cLight attenuation by a sound track. Response of a photocell.



As the film moves, the sound track itself varies, or modulates, the amount of light that reaches the photocell from the sound lamp.

The photocell then converts the light energy into electrical energy. The electrical current produced by the photocell is directly proportional to the intensity of the light that reaches it.

Photocells are made out of various photosensitive materials, each having a different spectral sensitivity. Virtually all 16 mm and 35 mm projectors have S-1 or silicon-type photocells, sensitive primarily in the infrared area. Therefore all 16 mm and 35 mm sound tracks must be able to modulate infrared radiation, which silver and to a lesser extent, silver sulfide are capable of doing. A sound track made of dye alone will not modulate the infrared radiation as effectively, reducing the signal-to-noise ratio significantly.

As the film moves past the sound aperture, the variation in the width of the track determines the amplitude of the signal generated, and the speed of the variation detertmines the frequency of the signal.

There are several types of variable -area recordings. A unilateral track consists of modulations that are generated perpendicularly to the longitudinal dividing edge between the opaque and clear portions of the track. A bilateral track, Figure 56 , uses modulations that are symmetrical about the longitudinal center line of the track. A dual bilateral track, Figure 56, has two bilateral images laid side by side; a multilateral track employs several bilateral images. The dual bilateral track is the most widely used because it minimizes distortion or signal loss resulting from any uneven illumination of the optical slit at the reproduction heads.

Photographic Sound-Track Reproduction

The effectiveness with which a photographic sound track is reproduced is a function of the spectral energy distribution of the illuminant, the spectral absorption of the soundtrack image, and the spectral response of the photoreceptor. The illuminant is usually a tungsten lamp having a comparatively low color temperature that provides relatively more energy in the red and infrared regions of the spectrum.

Due to the multilayer construction of most color films, the color of the light that exposes the sound-track image influences the trace

Figure 55 Figure 56A sound track as seen through the aperture.



characteristics and, therefore, is generally specified for the particular film concerned. Silver and silver-plus-dye sound-track images are normally suitable for use with any projector and are printed from a negative sound track. Silver sulfide sound-track images have somewhat lower quality. They are produced on reversal color films only and are themselves reversal images that are printed from a positive sound-track original.




WEDNESDAY, JULY 31

Projection

l Handling and Inspection of Motion-Picture Prints ¡ Common Causes of Abrasion and Wear

n Excessive Tension n Misalignment of Film in the Projector n Creased Edges n Run-Offs and Roping n Abrasions and Dirt

l Cleaning Motion-Picture Prints

The success or failure of any finished film lies in the viewing. Once a print is made, the final responsibility for the quality of the screen image rests with the projection equipment and the people who handle the print. This section covers the steps in inspecting a newly received print for flaws, the most common causes of film damage and abrasion, techniques for lubricating new prints, and techniques for cleaning film.

Handling and Inspection of Motion-Picture Prints

It is important to establish that the print meets your standards. When you receive a print, inspect it, following the recommendations below:

l Maintain constant tension while rewinding to provide a smooth, tight reel.

l Hold the film by the edges and wear clean, lint-free gloves while inspecting for damage or bad splices.

l Remake faulty splices correctly, whether cement or tape. l Insist on a replacement reel if major cuts and damage are noted

during your inspection. l Provide some means to maintain adequate relative humidity (60

percent is ideal) to help eliminate static electricity buildup in film transport systems.

Common Causes of Abrasion and Wear

To promote long life for your print, you should be alert to the causes of damage that can occur during projection. The five most common causes are discussed below:

Excessive Tension.

Too much tension in the film projection transport system usually results in objectionable projection noise and in perforation damage. If the film was properly lubricated at the laboratory, the source of the tension can be in the gate or at the feed and holdback sprockets.

l Check for deposits on the trap rails and check the gate tension. Adjust gate tension just tight enough to provide a steady screen image.

l Adjust tension on the projector reel spindles, if possible, to prevent singing sprockets.

l If all of these points check out satisfactorily, check the 35 mm


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prints for proper lubrication of the edges on the emulsion side. The first step is to vary the gate tension over the entire range. If no improvement is obtained, inadequate edge lubrication should be suspected. Sixteen-millimeter films should have an overall lubricant. The coefficient of friction of the emulsion side of the unsatisfactory film should be compared to a satisfactory film by the test described in ANSI PH1.A7 Methods for Detecting the Degree of Lubrication on Processed Photographic Film by the Paper Clip Friction Test. A coefficient of 0.2 or lower usually indicates a satisfactory level of lubrication.

Misalignment of Film in the Projector.

This problem can cause damage at the corners of the perforations and lead to splitting and breaking at the perforation edge.

l Check alignment of the film as it enters the feed sprocket or leaves the holdback sprocket.

l Check alignment of film in the projector gate. l Examine the print for damaged perforations before using it. (Order

a new reel or print, if necessary.)

Creased Edges. Film edges can become creased if:

l the projector is improperly threaded so that the pad roller creases the film over the sprocket.

l the film is under high tension and binds against some component or one of the roller flanges.

Run-Offs and Roping. This type of damage, often reported as sprocket marked, is caused when the film partially leaves the sprocket and rides over the sprocket teeth while under tension.

l Check for misaligned splices and remake them. l Check for fold-over damaged film sections; repair or replace the

section (or reel), if necessary. l Check to see if any unperforated tape covers perforations and

make necessary repairs. l Check the projector for proper threading and adjusunent.

Abrasions and Dirt. Primarily caused by careless handling, improper threading, and poorly maintained equipment this kind of film damage is readily seen by the viewer. If you can answer yes to the following questions, you are well on your way to minimizing the problems of dirt and abrasion.

l Is the projection area clean? Especially the floor and rewind bench? l Is the film riding correctly between roller flanges? l Is the print free of oil and grimy dirt? l Are smoking and eating (notorious dirt sources) prohibited in film

handling areas? l Is there enough tension during rewinding so that the film does not

slip on itself during fast starts and stops? (Much abrasion damage is caused by film slippage.)

l Do you use clean, lint-free gloves and hold the film correctly during rewinding and inspection?

l Do you avoid tightening a loose reel by pulling the film end until it snugs up? (This is another cause of abrasion damage.)



Cleaning Motion-Picture Prints

Clean and lubricate prints by drawing them between soft lintless cloths moistened with a preparation such as Kodak Movie Film Cleaner (with Lubricant). If a film is unsteady and noisy during the first projection, it may not have been lubricated at the processing laboratory. In this case, the film should be lubricated, not only to reduce noise but also to minimize film damage.

Cleaning cloths of the following types are usually satisfactory: a good grade of Canton flannel, a short- or medium-pile rayon or nylon plush, or a soft cotton batiste. These should be white, undyed, and free of fabric fillers and additives for stiffening. If in doubt the cloths should be laundered before use.

Place the film to be cleaned is placed on a rewind and thread the ladder stripe onto a take -up reel. As you rewind the film, draw it between two cloths moistened with the cleaner and lubricant. Constant light pressure provides continual contact between the film surface and the cloth. Do this slowly enough to permit the cleaner to evaporate completely before the film reaches the take-up reel.

Frequent moistening of the cloths is recommended because the solvent evaporates rapidly.* To avoid scratching the film with accumulated dirt particles, refold the cloths often so that only clean areas will be in contact with the film. If streaks are noticed on the film after lubrication, you can remove them by buffing with a soft cloth before projection.

Cleaning and lubrication should be accomplished with continuous, smooth rewinding of the whole reel. When you must stop to refold the cloth and apply more cleaner, back up the film about 1 foot (30.5 cm) before resuming the cleaning operation.

* Kodak Movie Film Cleaner (with Lubricant) does not contain carbon tetrachloride. Even so, you should use the cleaner with adequate ventilation. Forced-air ventilation should be provided. No matter what type of cleaner you are using, follow the instructions on the container.




WEDNESDAY, JULY 31

Dealing with a Motion Picture Laboratory

l Tips on Selecting a Laboratory l Laboratory Services: A Walk -Through

During post production, you will be spending quite a bit of time and money with a film laboratory. Locating the right lab is extremely important. Ideally, you should have some feeling for a lead early in the production phase, before you have many hours worth of exposed film on your hands and are wondering what to do with it. How do you find that lab? The purpose of this section is to explain how laboratory operations fit into your total production. First come some tips on selecting a lab. Next is a walk-through of laboratory operations during a typical production. The next section deals with processing and printing operations and equipment so that you can appreciate what can be done with your film once you've exposed it.



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WEDNESDAY, JULY 31

Tips on Selecting a Laboratory

Generally, the laboratory that gets your business will be the one whose capabilities best match the requirements for your particularjob. Laboratories differ in terms of the technical services they offer, personnel, track record on similar projects, size and location, prices, and so on. Weight all of these factors in selecting the right laboratory for the job at hand.

Every production has different requirements. The laboratory selected to do a production filmed in 35 mm for television distribution will probably be different from the one chosen to handle a job shot in 16 mm for reduction to super 8 to be used in point-of-purchase advertising. The challenge is to find the lab that can satisfy the greatest number of your needs on schedule and within budget. There are a number of trade-offs.

Consider the question of size. The big lab can usually offer lower prices due to their large-volume operation, more complete in-house services, and excellent quality control. The small laboratory usually offers custom handling and easy access to the right people for advice and counsel. But they may have to charge more to support their custom operation or subcontract more of the job.

Consider the location. If a laboratory is a significant distance from your place of business, you will be faced with the potential hazards and increased costs of shipping valuable footage to and from the lab. Daily communications with the lab may also be more difficult.

Consider your confidence in the laboratory. The selected laboratory should be looked upon as a silent partner in the production of a motion picture. The laboratory should be taken into the producer's confidence, kept informed about the films and photographic techniques being used, advised of the specific objectives, and alerted to any problems that might develop. Given this relationship, the laboratory can assist and simplify your endeavors. You should select a laboratory you feel takes your interests seriously.

These important steps in your production can be smoothed considerably if adequate communications are established right from the start. Both you and your laboratory should know what is expected-and when to expect it.

l Know your needs. Have a good idea of what you want from a laboratory and then talk about those needs with several laboratories before you make a choice. In your discussions, be sure to relay your ideas about such things as editing, dubbing, special effects, animation, etc, so the lab can help you accomplish these tasks in the best way possible.

l Get acquainted. Once you have made your choice of laboratories, get to know, as well as possible, the people who will do your work. Tell them as much as you can about yourself, your needs, and your style. The more you communicate with them about yourself and your production, the better they can serve you.

l Get it in writing. Face-to-face discussions and telephone calls are


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necessary for efficient work flow; but when it comes to specifying what you want, when you want it, and how much it will cost, a carefully written document-the purchase order-is a must.

Listed below are some of the principal services offered by commercial motion picture laboratories. Few laboratories will offer all the services listed but most of them will provide a major portion.

l Processing camera film. (Special overnight pickup and delivery, or weekend service is available in some places by prearrangement) Find out what processes are available, including special techniques (e.g. flashing or force processing).

l Furnishing advice to help with technical or even aesthetic problems.

l Printing and duplicating from camera films for workprints or releaseprints. Most laboratories will print or duplicate the camera film after it is processed. They may also hold the original in their vault and forward the print for use as a workprint. Thus the original is protected from damage in handling until it is needed for final conforming.

l Black-and-white printing from a color original to produce a workprint for sound editing.

l Edge numbering of originals and workprints to facilitate editing. l Editing, cutting, splicing, and assembling as directed by the

producer. l Conforming by matching the original camera film to the workprint

as edited by the producer. l Optical effects which these include dissolves, wipes, fades, freeze

frames, etc.


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WEDNESDAY, JULY 31

Laboratory Services: A Walk-Through

To help you visualize the way a laboratory's operations interact with you and your production, this walk-through gives you three views of scheduling. First is a flowchart of operations from preproduction through various laboratory operations to delivery of the edited, printed film. The chart shows a graphic description of the close communication between lab and cinematographer that produces a satisfactory final print. Next is a narrative about the production of a film for television that demonstrates the behind the scenes laboratory work that keeps a production on schedule. Last is a day- to-day schedule, from shooting to release print, of this production.

Now, let's describe our show. This weekly one-hour series is produced by a major studio that has a network contract requiring the production of 24 episodes. The show routinely includes practical location photography (day and night). Six to seven days of filming are common for each show.

Here's how the laboratory fits into the production. On most days, the production company's exposed 35 mm negative is at the studio's camera department by 7:00 p.m. A truck from the laboratory picks up the negative along with those of several other production. Often, the truck makes several trips throughout the evening.

The first batch of negatives arrives by lab truck, is sorted by the directions on the film cans (flashing, forcing, priorities, etc.), and prepared for processing. The rolls are processed and sent to negative


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assembly where the out-take negative is removed and stored for safekeeping. Rolls (approximately 1,000 ft) of print-take negative are assembled and spliced. The roll is ultrasonically cleaned and printed at exposure values that had been derived through a "fine-tuning" of timing information obtained early in the production season on the laboratory's electronic color analyzer. The daily print is developed and screened by the laboratory customer representative usually between 6:00 and 9:00 a.m. The print is projected full aperture at approximately 120 ft/min (32 frames per second) so any film, camera, or laboratory problems can be seen. The daily prints are delivered to the production company's editors by 9:00 am. for syncing with the sound track that has been transfered from 1/4-inch magnetic tape to 35 mm magnetic film. At 1:00 p.m. the director and other production personnel screen the synced dailies on double-system projectors.

The laboratory won't be involved in this particular episode in the series for about two weeks (in some cases for two months, depending on the activities of the production company). During this time, the studio is editing, dubbing and mixing sound, and preparing optical effects.

The laboratory's next job is to assemble these elements and generate the final composite prints for this episode. The network usually requires two 35 mm prints (for New York and Los Angeles) and three to fifteen 16 mm prints. Two of the 16 mm prints are backup prints for the 35's, one is for Canadian television (which usually is broadcast 3 to 4 days before the U.S. air date), and the remainder are split regionally within the network system.

This phase begins with close communications between the production company's negative cutter and the laboratory. As reels near completion, the negative cutter delivers the cut negative with instructions to the lab. The reel may be only 90 percent complete, but the lab can begin to splice and notch the negative, leaving leader in the areas that are not firm or are awaiting inclusion of laboratory -created segments (dissolves, fades, and titles) primarily on color reversal intermediate (CRI) or color intermediate film stock. The optical effects elements are usually created by an independent optical house rather than the laboratory.

When the negative has been spliced and notched, it is timed on an electronic analyzer to determine the exposure values to be used in the printer. The timing information is used on a proof printer which prints only a few frames of each scene. This proof print is screened (single -frame projection) to identify any further color or density corrections required. A complete composite print (answer print) is then made and evaluated on the analyzer. Once the answer print has been accepted by the producer, a second 35 mm print is made. A 16 mm wet-gate reduction CRI is made, using the final timing derived for the 35 mm answer print. From this 16 mm reduction, the required 16 mm prints are contact printed.

On the fourth day after the laboratory received the cut negative, the answer print is screened at the laboratory for representatives of the production company and the network, and the print is approved.

Day-to-day Schedule of the Production

Starting on Hay

Event Huration



Preproduction 1-6 weeks. Depends on how many locations to be scouted and/or how many sets to be constructed.

Days 0-6 Production Photography-6 days.

Day 2 Postproduction 2-8 weeks Laboratory opertations begin during shooting and include processing the negative, daily workprint printing, cutting the workprint into sequences, making optical effects, adding stock footage and sound effects, making titles, and dubbing (voice, sound effects, and music). Optical effects are scheduled whenever the individual scene elements are available. Several labs may be involved in some phase of these operations.

Day 12 1. First Cut Includes action and voice only, in rough sequences. No opticals, titles, sound effects, although some opticals and titles are being made.

Day 24 2. Final Cut Workprint. More precisely edited into final form. Some opticals but no titles or sound effects.

Days 25-31

3. Negative Cut Music composed and scored, sound effects made, opticals and titles prepared, editing finished. Camera negative physically cut to conform to final cut of the workprint. Dupe negatives spliced in where there are opticals and title negative footage added. Actual splicing is done at the laboratory.

Day 32 4. Dubbing 1-3 days. All sound materials (live music, recorded music, voice, sound effects such as gunshots, footsteps, etc) combined into a composite magnetic sound track. Magnetic track transferred to optical track.

Days 34, 35 & 36

5. First Trial Film shows aesthetic defects in some areas. Needs tightening up and polishing, slight recutting. Some elements missing in titles.

Day 37 6. First Answer Print 35 mm

Contains everything; becomes New York air print.

Day 38 Second Answer Print

Slight color corrections; becomes Los Angeles air print.

Day 39 7. 16 mm Prints

Reduction CRI and ten 16 mm prints.




WEDNESDAY, JULY 31

Motion Picture Laboratory Operations

l Processing Equipment l Construction of Containers l Transport Design l Access Time l Time and Temperature l Agitation l Mechanical Specifications l Process Control

One important consideration when selecting film-one too often overlooked-is the processing requirements for a given film and the printing needs for the whole production. One way to better appreciate the sophisticated technology that turns your exposed camera film into good projection film is to understand the processes and equipment in the modern film laboratory. In this section, we will describe the operations and equipment involved in processing and printing your film.

Processing Equipment

The modern motion-picture laboratory uses the continuous processor, a machine that provides the most efficient way of handling long lengths of film. Other kinds of equipment can be built or purchased for development of small amounts of black-and-white footage, but the continuous processor meets the quantity and quality demands of professional processing. In essence, the continuous processor moves film through the appropriate sequences of developers, fixers (or stop baths), washes, and dryer at a carefully controlled speed. The processor also controls solution temperature and agitation to produce optimum results for the particldar kind of film being processed.

Construction of Containers

Glass, hard rubber, polyethylene, 316 stainless steel, and titanium are the materials most commonly used in the construction of containers for mixing, storing, and using photographic solutions.

Not all metals are suitable. Tin, copper, and their alloys may cause serious chemical fog or rapid oxidation when used with developers. Do not use aluminum, zinc, or galvanized iron with either developers or fixing baths.

Transport Design

The film follows a helical path by moving on partially or totally submerged banks of rollers through the various solutions ( Figure 57). Squeegees (Figure 58) or wipers located between the different tanks remove most of the liquid from the film surface. The most common method of moving film through a processor is by friction between the rotating spools and the base side of the film. The other major method is by sprockets incorporated on the spools which engage the film perforations.


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The film path through the processor wet sections permits only the base side of the film to contact the rollers. In this way, the emulsion is protected from possible physical damage that might occur if the soft, wet emulsion came in contact with the plastic spool surfaces. However, in the dry sections (feed-on and take-off) of some processing machines, there may be emulsion- side rollers. These are usually under cut in the image area and are designed to contact only the edges or perforation area of the film. Some rollers have ridges that touch only edges of the film, or the rollers can be flat and covered with soft-touch tires for uniform film support across the roller width and to prevent scratching of the support in the image area. See Figure 59.

Access Time

Two of the most widely discussed and perhaps the most misunderstood items relating to any processor are speed and access time. Speed refers to the time required for a specific point on a film to travel a specific distance and is measured in feet or meters per minute. Access time refers to the time it takes a particular length of film to be completely processed. Regardless of machine transport speed, which can range from 15 to hundreds of feet per minute, film cannot be processed faster than the total of the times required in each solution. For example, when a machine running Process VNF-1 is loaded and processing film, it will be 15 minutes 15 seconds before the first foot of film enters the drying cabinet no matter what the speed of the machine. However, the time for completing various lengths of film once the process times are met is in direct relation to the machine speed. If the machine speed is 15 fpm, then a 15-foot -long film will take 14 minutes 15 seconds plus 1 minute to complete the process. With a 150-foot roll, access time will be 14 minutes 15 seconds plus 10 minutes.

Time and Temperature

In black-and-white processing, time and temperature may vary widely among motion picture laboratories. Each laboratory selects the appropriate development times and temperatures for the films being processed in a particular machine and with a particular formula. This is accomplished by producing a time-gamma curve, as discussed in an earlier chapter. (Some modifications in the control-gamma aim may be

Figure 57 Figure 58 Figure 59Helical path of film through a single rack and tank assembly

This type of wiper-blade squeegee assembly is used on many processors.

Roller undercut in image area.



necessary depending upon the type of sensitometer or densitometer being used.)

For color films, specified temperature tolerances, particularly those for the developers, are critical. Developer tolerances of +/- 0.3ºC (+/- 0.5ºF) are typical. Appreciable deviation from these limits results in speed and color- balance changes. Many commercial motion picture laboratories have found it feasible and profitable, in terms of consistent quality, to control the developer temperature to within +/- 0.15ºC (+/- 0.25ºF), or even less. Process ECN-2 requires that the developer temperature be held within +/- 0.1ºC (+/- 0.2ºF).

Controlling processing time is also more critical with color films than with black-and-white films because any changes that occur in color emulsions may not be equal in all layers. Improper color reproduction can result from speed shifts, contrast changes, increased fog, etc., in any of the layers. Therefore, a good lab adheres closely to the exact processing specifications for the particular equipment and materials.

Agitation

If exposed photographic materials are placed in a developer and allowed to develop without movement, the action slows down because the developing chemicals in contact with the film surface become exhausted. If the film or the solution is agitated, however, fresh solution is continually brought to the emulsion surface, and the development continues. An equally important effect of agitation is prevention of uneven development that may result in mottle, a nonuniform density in the print that makes it look blotchy. If there is no agitation, the exhausted solution, loaded with development by- products, may flow slowly across the emulsion from dense areas to less dense areas and produce uneven streaks. Agitation keeps the solution uniform throughout and avoids uneven development. In color processing, proper agitation is especially critical during the initial development step. The recommended agitation techniques will vary, depending upon the process and equipment being used. The film movement, as it passes through the developer solution is not always sufficient to create adequate agitation.

Mechanical Specifications

If film is to be processed satisfactorily as it moves through the machine, it must be immersed in solutions of the correct temperature for the proper length of time. In addition, processing solutions must be adequately replenished and filtered, and sufficiendy agitated. These requirements are commonly called the mechanical specifications.

The only valid processing change-made for the purpose of force processing (for more camera speed under low-light conditions)-involves increasing the developer (camera negative) or first developer (reversal camera film) time and/or temperature.

The time that film is immersed in a particular solution depends upon the length of the film path in each tank and the machine speed. Generally, time is fixed by the number of rollers per rack and the number of racks threaded in a tank. Usually, individual rack times can be changed by rethreading the rack or using a rack equipped with an adjustable lower-shaft assembly.



Temperatures on most processors are controlled automatically, often to within +/- 0.1ºC but can usually be adjusted manually to accommodate any desired temperature changes. The laboratory also keeps a highly accurate thermometer available to double check the processor temperature gauges.

Process Control

The degree of development in a negative-positive process or first development in a reversal process is the most important factor in determining the final image quality. Careful control is critical at this point. Development is affected by the temperatures and chemical composition of the developer (or first developer), the time of contact between the film and the solution, and the degree of agitation. The other processing steps are also affected by the same factors.

When all is well with the process, the output from the continuous processor will be good pictures. While these pictures can be evaluated subjectively by simply looking at them, the most accurate evaluation is an objective measurement Sensitometric control strip density values, when plotted in graphic form, give an operator that objective information about the condition of the process. These measurements are made before, during, and after a processing run for maximum control of quality.

The operator also checks the physical operation of the machine periodically to ensure good results. A good lab observes the following practices in the physical control of a process:

l Use of correct processing temperatures, which are checked often. Thermometers and temperature -controlling devices are calibrated periodically to insure that the instruments are operating properly. The temperatures of all solutions are kept within specification to minimize dimensional changes in the emulsion.

l Use of recommended processing times. Machine speed is checked by carefully measuring the time it takes for a given length of film to pass a specific point. Knowing it is possible to use an incorrect processing time when a machine uses different thread-ups for different film stocks, the careful laboratory checks the solution times every time there is a threading change. Consider that, for black-and-white negative or positive process, one might run up to seven films having nine possible development times through Developer D-96 in the course of a few hours.

l Use of the recommended replenishment rates. Accurate replenishment increases the useful life of solutions to a great extent by replacing ingredients that are depleted and maintains the process at a constant, efficient level. To prevent serious out-of-control situations and chemical waste, laboratories routinely check the accuracy of their replenisher delivery systems.

l An accurate daily record is kept of conditions affecting the process, including developer temperature, amount of film processed, volume of replenisher added, and identification numbers of control stops processed at particular times.




WEDNESDAY, JULY 31

Marketing a Film

l FiIm as a Business Tool l Potential Clients l Client's Communication Requirements l Reaching Agreement on Need for Film

"People don't buy goods and services; they buy solutions to problems. People are accustomed to learning through film."

l Filmmakers who learn how to market and how to communicate with clients are the ones who make films.

l You have nothing to sell, of course, except yourself-and the promise that you can deliver a film that meets your client's needs.

l Don't try for a film that will win prizes. If you try for a film that will best serve your client's needs, you will find yourself with a prizewinner . . . and a recommendation for another job.

l Your reputation is as good as your last film. You build a reputation by taking care of business every day as though your reputation were at stake, because it is.



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WEDNESDAY, JULY 31

Film as a Business Tool

"Corporations are closer to the film medium, because they make commercials and they're more exposed to film; the educational foundations are not the best source of funds for films."

Knowing how to make a film-kowing how to use the medium to communicate a message-is not enough if you are to become successful. You must also know how to communicate with people who need the films so that you can get a chance to use your creative talents. In business, that's known as marketing.

Your marketing should begin with a sensible look at what you have to offer. In reality, film is not what you have to offer. What you have to offer are solutions to problems, using film as the medium for communication. That's what nontheatrical filmmaking is all about.

There are several areas open to the nontheatrical filmmaker-business, education, special interest groups, vacation resorts, governmental agencies. All have a use for sponsored nontheatrical films-films that teach, films that promote, films that pass along information.

Basically, there are three types ofcommunication problems: Those related to skill and knowledge, motivational problems, and problems of information; and, of course, some communication problems are a combination of the three.

Problems in the skill-knowledge area usually involve situations where someone lacks the understanding necessary to perform a job. People have to be trained to make products. People have to be instructed in safety procedures. People have to be coached in selling the product. The idea is this: People who know more are more effective. That's a good investment.

In the motivational area, the problem is that someone may not want to do a job. Most recognize that people who want to work are more productive and will work harder toward a solution to the problem. Motivational problems can also involve prospective clients. The solution in this case can usually be found in the area of more effective advertising and sales promotion.

In the informational area, the problem is what most people would refer to as public relations. Corporate and product visibility is very important to most companies, since exposure and goodwill help sell products. A company that perceives a need for solving informational problems will invest in a solution that best reaches its audience.

The point is, business spends money to make money. A smart business person will provide the money to make a film once there is an understanding that film will help solve a problem. Your job is to discover where a film will help.

Potential Clients


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"Organizations (business corporations, universities, churches, hospitals) have internal communications problems, such as training their employees, communicating government regulations and rules, motivating people, and creating a sense of community among their people so they work as teams; those are common problems for any kind of organization."

Every company is a potential client. First, start with a list of companies in your area. Use the phone book, a Chamber of Commerce listing, or the Fortune 500, trade listings. Some companies, because of size, will be obvious prospects. Of course, if those companies use film, they probably have many other filmmakers calling on them already. But you have nothing to lose by offering your services as well. It's true that you may not have anything to offer that they are not getting now, but you'll never know unless you contact them.

"Trade journals will tell you what's going on and what kinds of films are being made and who's making them. Also, industries will address business problems in their annual reports . . . Read the business page in your newspaper; look to see where trends are happening."

There may be several people to contact in each company. Internal structures are easy enough to penetrate if you keep the cornmunication needs in mind. One way to get started is to call the switchboard or drop by the lobby, and ask questions: "Could I speak to the manager of the Training Department?" "Who is in charge of Sales Promotion?" "I'd like to talk to someone in Corporate Relations." . . . and so on. It may take a while, but most people are helpful once they understand that you are trying to find someone you can show your talents to.

Within each company there may be several different departments that have a need for film. You will find that department names vary greatly -AV Services, Advertising and Sales Promotion, Media Services, Marketing Development-but their purposes are all the same: to solve communication problems. Somewhere in these departments you will find one or more prospects. They may deal directly with you; on the other hand, they may be required to request the work through a central medial department Don't forget, a company with one prospect for you probably has two.

"To reach individuals in a company, you have to first work through the 'corporate tree' and pick the branch that you feel needs a film."

A second way to get potential clients is to offer them a solution to a problem you perceive before you ever meet. This involves a good deal of homework. Look in trade journals, annual reports, and business papers and magazines. Each will give you an idea of current business problems. It may spark an idea that you can develop into a proposal. Once your ideas are thought out, place a few phone calls to the company until you find someone who is willing to briefly discuss you idea. If that person seems interested, you can send the full proposal for further investigation.

If the company is not interested in that particular proposal, you will have shown yourself to be someone interested in solving its problems, and that alone may help you get some work.



And don't forget that your prospects may be working with cyclical budgets. For example, the textile industry will probably be most busy twice a year and will have to introduce new products-in the spring and fall. Car manufacturers come out with their new products in the spring and fall. Summer recreation has an obvious selling period, as does winter recreation. Budgets for producing work becomes available before those selling periods. So, your marketing efforts have to coincide with the budgets, not with the selling periods. Direct your efforts toward the future; if your prospect doesn't save money now, the money will come eventually.

"What you have to get a little more aware of, and perhaps a heck of a lot more of, is corporate budgeting. Corporate budgets have certain approval cycles, certain processes, and there are times that you can get at the money and times that you can't. You don't want to do all your homework and then go in there and find that there's no water in the well."

Before you ever reach a potential client's desk, you have to decide why you are going to meet with that person. Certainly you want to introduce yourself and, if possible, show some samples of your work. But you should be trying to do more than that so that you can best define what you have to offer. Among other things, you will want to find out what communications needs exist in the company, how these needs are currently solved, and whether the person you are talking to has the power or influence to hire you.

When you meet someone for the first time, you have the opportunity to begin a lasting business relationship. You know what you can do. Now is your chance to find out what you can do for your prospect. You can only do that by determining what your prospect needs.




WEDNESDAY, JULY 31

Film as a Business Tool

"Corporations are closer to the film medium, because they make commercials and they're more exposed to film; the educational foundations are not the best source of funds for films."

Knowing how to make a film-kowing how to use the medium to communicate a message-is not enough if you are to become successful. You must also know how to communicate with people who need the films so that you can get a chance to use your creative talents. In business, that's known as marketing.

Your marketing should begin with a sensible look at what you have to offer. In reality, film is not what you have to offer. What you have to offer are solutions to problems, using film as the medium for communication. That's what nontheatrical filmmaking is all about.

There are several areas open to the nontheatrical filmmaker-business, education, special interest groups, vacation resorts, governmental agencies. All have a use for sponsored nontheatrical films-films that teach, films that promote, films that pass along information.

Basically, there are three types ofcommunication problems: Those related to skill and knowledge, motivational problems, and problems of information; and, of course, some communication problems are a combination of the three.

Problems in the skill-knowledge area usually involve situations where someone lacks the understanding necessary to perform a job. People have to be trained to make products. People have to be instructed in safety procedures. People have to be coached in selling the product. The idea is this: People who know more are more effective. That's a good investment.

In the motivational area, the problem is that someone may not want to do a job. Most recognize that people who want to work are more productive and will work harder toward a solution to the problem. Motivational problems can also involve prospective clients. The solution in this case can usually be found in the area of more effective advertising and sales promotion.

In the informational area, the problem is what most people would refer to as public relations. Corporate and product visibility is very important to most companies, since exposure and goodwill help sell products. A company that perceives a need for solving informational problems will invest in a solution that best reaches its audience.

The point is, business spends money to make money. A smart business person will provide the money to make a film once there is an understanding that film will help solve a problem. Your job is to discover where a film will help.

Potential Clients




"Organizations (business corporations, universities, churches, hospitals) have internal communications problems, such as training their employees, communicating government regulations and rules, motivating people, and creating a sense of community among their people so they work as teams; those are common problems for any kind of organization."

Every company is a potential client. First, start with a list of companies in your area. Use the phone book, a Chamber of Commerce listing, or the Fortune 500, trade listings. Some companies, because of size, will be obvious prospects. Of course, if those companies use film, they probably have many other filmmakers calling on them already. But you have nothing to lose by offering your services as well. It's true that you may not have anything to offer that they are not getting now, but you'll never know unless you contact them.

"Trade journals will tell you what's going on and what kinds of films are being made and who's making them. Also, industries will address business problems in their annual reports . . . Read the business page in your newspaper; look to see where trends are happening."

There may be several people to contact in each company. Internal structures are easy enough to penetrate if you keep the cornmunication needs in mind. One way to get started is to call the switchboard or drop by the lobby, and ask questions: "Could I speak to the manager of the Training Department?" "Who is in charge of Sales Promotion?" "I'd like to talk to someone in Corporate Relations." . . . and so on. It may take a while, but most people are helpful once they understand that you are trying to find someone you can show your talents to.

Within each company there may be several different departments that have a need for film. You will find that department names vary greatly -AV Services, Advertising and Sales Promotion, Media Services, Marketing Development-but their purposes are all the same: to solve communication problems. Somewhere in these departments you will find one or more prospects. They may deal directly with you; on the other hand, they may be required to request the work through a central medial department Don't forget, a company with one prospect for you probably has two.

"To reach individuals in a company, you have to first work through the 'corporate tree' and pick the branch that you feel needs a film."

A second way to get potential clients is to offer them a solution to a problem you perceive before you ever meet. This involves a good deal of homework. Look in trade journals, annual reports, and business papers and magazines. Each will give you an idea of current business problems. It may spark an idea that you can develop into a proposal. Once your ideas are thought out, place a few phone calls to the company until you find someone who is willing to briefly discuss you idea. If that person seems interested, you can send the full proposal for further investigation.

If the company is not interested in that particular proposal, you will have shown yourself to be someone interested in solving its problems, and that alone may help you get some work.



And don't forget that your prospects may be working with cyclical budgets. For example, the textile industry will probably be most busy twice a year and will have to introduce new products-in the spring and fall. Car manufacturers come out with their new products in the spring and fall. Summer recreation has an obvious selling period, as does winter recreation. Budgets for producing work becomes available before those selling periods. So, your marketing efforts have to coincide with the budgets, not with the selling periods. Direct your efforts toward the future; if your prospect doesn't save money now, the money will come eventually.

"What you have to get a little more aware of, and perhaps a heck of a lot more of, is corporate budgeting. Corporate budgets have certain approval cycles, certain processes, and there are times that you can get at the money and times that you can't. You don't want to do all your homework and then go in there and find that there's no water in the well."

Before you ever reach a potential client's desk, you have to decide why you are going to meet with that person. Certainly you want to introduce yourself and, if possible, show some samples of your work. But you should be trying to do more than that so that you can best define what you have to offer. Among other things, you will want to find out what communications needs exist in the company, how these needs are currently solved, and whether the person you are talking to has the power or influence to hire you.

When you meet someone for the first time, you have the opportunity to begin a lasting business relationship. You know what you can do. Now is your chance to find out what you can do for your prospect. You can only do that by determining what your prospect needs.




WEDNESDAY, JULY 31

Client's Communication Requirements

"You have to find out first of all how they think, how they operate, what their business is like, and how they make decisions."

There are two ways to approach a communication problem. One way is to let the client take control; you do that by talking about yourself, your attitudes, your previous successes with other similar problems. This approach is not particularly successful. A more effective way is to take control yourself-define your meeting; you're there to get business. You can help yourself by paying attention to the problem. Listen to what the client has to say and ask questions that will reveal why your client thinks of the problem as unique.

But it's not enough for you to discover your client's needs. You also have to help the client's needs. You also have to help the client really understand the needs and reach agreement on them. Only when you have reached that point can you begin to talk about solutions. You may have to hold several meetings before you begin to talk about film, which is just the medium for solving the problem.

The importance of good communication skills in determining your client's needs cannot be overestimated. Remember, you are in marketing as well as filmmaking. Marketing requires certain skills that you may never have considered.

Keep in mind that your job is to solve your client's problem. You may understand the problem one way; your client may understand the problem differently. You must learn to listen carefully and question your client skillfully so that you can both agree on a definite solution to the problem. You may be able to create a great film; but if your client isn't happy, it may be your last film.

Reaching Agreement on Need for Film

At the end of your first meeting with a prospect, some action has to be taken if you are going to continue to work with the prospect and perhaps do a film. This, again, is continuing your control. In business, this point in the action is called a close.

What it means is that you must get your prospect to agree to do something. You may have to suggest what to do next. It may be to write a proposal, meet with other people, or continue discussing how you might help the company. You have to do something or the prospect is lost to you.

If you continue to work with the prospect, you will find that at every point along the way there are places where action must definitely be taken. For example, when you have submitted a proposal which in many cases is simply to ask: "Shall we go ahead with it then" or "Does it meet with your approval?"

When you ask for a positive action and the prospect says No, don't give


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up, not yet. First take the time to find out why your prospect has said no. It may be that the proposal you have submitted doesn't clearly solve the problem. In that case, your job is easy; just write another proposal. Perhaps the client isn't convinced that you can do the job. In that case, you can ask the client if references from other people would be helpful.

Whatever you do, don't let the word no stop you until you find out why. And when you find out why, close-that is, take an action that will get you a yes.

At some point in the filmmaking process-before you begin production-you will have to communicate with people who hold the purse strings . . . you will have to get the proposal approved. Even though your client may understand the creative and technical aspects of filmmaking as well as you do, somewhere along the line you will have to talk to people who relate to costs differently than you. Keep in mind that your client's company doesn't need a film per see, it needs solutions to problems. The film you create will have to solve those problems in cost-effective ways. It goes back to the three kinds of communication needs. Ask yourself a few questions: Will the company be able to sell more porducts? Will it be able to train people better? Will it now be able to communicate information to more people more effectively? Will employees be sufficiently motivated by the film to justify the cost of producing it?

All of these questions are related in one way or another to profit. If the company can sell more goods and services, get more work done, disseminate more necessary information using audiovisuals, and if it can get more in return than it spends on your film, then that is a gain for the company and the kind of "bottom line" that interests those who have final approval of the project.

"What gives a company the results it's looking for? A film may be your end product, but it's not their end product . . . film is a medium you give them to help solve their internal or external communication problems."

To summarize, finding and keeping clients is a sequential marketing process. Even though you are only marketing yourself, there is a logical order of steps to go through in order to get down to business of making a film.

Basically, it involves doing things one step at a time. First, you have to decide where the potential jobs are. Second, you have to find out whom to talk to. Before you ever see that person, you have to do some homework in two areas. Find out as much as you can about your prospect's organizational setup and communication needs. Then, decide what it is you have to talk about so you can present yourself properly.

When you see the prospect, you will go through a series of steps involving questioning and listening to find out the communication needs of the prospect and of the company. Once you know these needs, you have to present yourself as a person-a filmmaker-who can offer some solutions. And, if the prospect looks good, you have to close-which means that, if nothing else, you decide when to meet again to talk more specifically about certain projects or needs within the company.

After you have a project or perhaps an order to get a project, you have to write a proposal based on the objectives that you and your client have worked out. You may even have to write a second proposal detailing the



business advantages to the company as well as alternative proposals.

And finally, you have to secure a contract before you begin production. At this point, your marketing job is not over. Even though you are now concentrating most of your efforts on making the film, you must still stay in close contact with your clients to keep them up-to-date on the progress of the film and secure the necessary approvals along the way.

Marketing a film is very much like producing a film; every step must be considered in order to meet the client's needs as the client sees them. Don't let the term frighten you . . . it's simply a matter of taking care of business.

Filmmakers tend to think of themselves as artists, apart from the clutter of the business world. But no matter how alien the concept of marketing seems, it is still a skill that must be learned and developed. Why? Because marketing is a skill that will help you make the kind of films you want.

"Take that next step beyond your filmmaking skills . . . business skills don't decrease your freedoms . . . a lot of people are afraid that, 'If I take on business skills, I'm going to spend all my time with tax accountants; you aren't . . . it means being a little more equipped, more astute, than the next person-doing more than the client expects."




WEDNESDAY, JULY 31

Distribution and Promotion

l General Market Considerations ¡ Educational ¡ Special Interest ¡ Broadcast Television ¡ Cable Television ¡ Vacation Resorts

l Film Ingredients ¡ Running Time ¡ ProfessionaI Versus Industrial Talent ¡ Film Content

l Distributor Services ¡ Promotional Ideas ¡ Print Inventory ¡ Supporting Materials ¡ Film Maintenance

l Your creative work is of little value unless you have an audience. l If you don't have a plan, it will stay in the can. l When you target your audience, you target your potential for

payback. l There are as many outlets for good films as there are good films. A

good film is one that is aimed at a particular audience. You must give the audience a chance to see it by making it visible with promotion, available with distribution, and usable with support materials and proper maintenance.

The distribution and promotion phase is, many times, a matter of rote. Many companies have predetermined distribution channels, especially with materials created for internal use (training outlets or salespeople) or for well- established clients (dealers or distributors). You may, however, be able to help your client choose the distribution format. Will the film be shot in 16 mm and converted to 35 mm, then converted back to 16 mm for television use? Will it be shot in 35 mm and converted to 16 mm for distribution? Will the same film have several uses in several formats?

Your client's answers will help you determine both the original format and the distribution format, determine costs for the total needs of your client, and avoid serious mistakes when choosing production techniques. A high contrast black-and-white film, for example, might be dramatic in a theater setting but look muddy or washed out on a television screen. Inadequate planning can ruin even your best work or cause unnecessary costs for your client, and for that reason the distribution format must be considered in your proposal.

Many times, distribution and promotion are the critical points in the decision to make-or not make-a film. Is there an audience for the film? How will you get it to them? How will they know the film is available? These questions must be addressed in the planning stages; and when the answers are not obvious, it is very good business to consult a professional distributor.

Early involvement with a professional film distributor is essential in


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getting a general-interest film production to its target audience. Whether you are aiming at a large, single audience or widely diversified audiences, a distribution service is an excellent vehicle for publicizing and communicating your film's message.

This part covers general considerations for distribution planning, the potential distribution channels for reaching mass audiences, important film ingredients influencing distribution methods, and the many services offered by the distributor (including promotional pieces, print inventory, supporting materials, film maintenance).


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WEDNESDAY, JULY 31

General Market Considerations

"We have just made a new film. Could you come over and take a look at it and give us some suggestions for distribution?" This type of request (which originates from film producers or from the sponsors of a producer's film) is too often heard by professional film distributors. The above question should be answered at the planning stage, not after the film is in the can. Early in the game, consider not only why the film, but also where the film.

Unfortunately, film producers are often not well-equipped to communicate to their clients all of the effective distribution alternatives. If you feel at all uncomfortable with any of the distribution areas, get in touch with a film distributor who can answer your questions and handle your specific needs.

Not all industrial films are suitable for mass distribution, nor are their target a mass audience. Films are often produced to sell a client's product, point of view, or service to an extremely narrow market (e. g., medical films, military films). These films are carefully aimed at the target audience and usually delivered directly by the sponsor or his or her sales personnel. Professional distribution is normally not required for this type of film. This part is really addressed to the films that are made for unclassified or general audiences.

Non-theatrical films are generally directed to one or more of the five potential channels of distribution:

l Educational l Special-interest groups l Broadcast TV l Cable TV l Vacation resorts

Schools and special-interest groups account for the greatest utilization of sponsored films. Your films can also receive considerable visibility through the other four distribution channels. If you want to target your films at these areas most effectively, you should really contact a professional distributor.

Educational

There are four major subcategories in the educational field: grade school, junior high school, senior high school, and college. And, even within these, there are many other subcategories, such as: boys, girls, and coeds.

Instructional films covering the following subject areas (among many others) are regularly shown to school-age students:

l Home Economics l Science l Physical Education


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l Health l Social Studies l Business and Economics l Vocational Guidance l Arts and Crafts

Also within this age range are various non-school youth organizations such as: Boy Scouts, Girl Scouts, Little League, and other sports groups, YMCA, YWCA, etc.

Special -Interest

The special-interest grouping encompasses business and professional organizations, religious groups, civic and social clubs, etc,. Listed below are many of the areas that make up this large and diverse category:

l Business and Industry (e.g., oil companies, computer companies, electronics factories, automobile companies)

l Service and Fraternal organizations (Rotary, Kiwanis, Masons) l Church groups (Finance Committees, Pastor-Parish Relations) l Sports groups-hunting, fishing, automobile clubs (NASCAR, SCCA),

ski clubs, hiking clubs l Federal Govemment agencies (Internal Revenue Service, Health,

Education, and Welfare Department) l State agencies (Department of Motor Vehicles, Transportation

Department) l Military branches (Army, Navy, Air Force, Marines) l Hospitals

The above is not intended to limit the possibilities, but merely to point out the broad range of potential target audiences within the special-interest category.

Broadcast Television

Broadcast television (commercial and educational) provides the quickest method of exposing many thousands of viewers to your film at one time and at a surprisingly moderate cost. Your film should be original and aesthetically pleasing to be accepted for TV broadcast; it should also be appropriate for an audience of varying ages, educational backgrounds, and interests. A couple of points to remember are that running times of either 13 1/2 or 27 1/2 minutes are most suitable for the average TV station, and less prevalent film lengths include 3 to 5 minutes and 7 to 10 minutes for use as fill material (full-length film or sports event running less than a two-hour programming slot). Generally, TV stations broadcast from 2 to 4 hours of sponsored films every week.

Cable Television

Cable television (CATV) is a steadily growing market. Similar to broadcast TV, CATV enables you to show your film to many of the cable viewers (a total of about 10 million homes in 7,000 communities) at a number of locations throughout the country. Again, your film should have wide audience appeal, be approplate for many geographic areas, and run either 13 1/2, 27 1/2, 3 to 5, or 7 to 10 minutes. Although your film may be meant for a certain special-interest regional group, it could also be of interest to people in other communities.



Vacation Resorts

Vacation resorts are another excellent area for promoting your films. You have the opportunity to reach many community adult groups that do not normally meet in the summertime. Movies are frequently offered for evening entertainment by the management for resort hotels, motels, camps, or other similar vacation habitats. This approach enables you to communicate with a wide range of relatively affluent viewers (with the appropriate type of film-skiing, fishing culture) in a leisurely and relaxed atmosphere.




WEDNESDAY, JULY 31

Film Ingredients

In addition to considering the categories of audiences and potential distribution channels, you should also examine some of the important parts of a successfully designed film: the running time, the advantages and disadvantages of using professional talent versus industrial talent, and the film content.

Running Time

The running time of your film will have a significant effect on the way it is distributed.

Generally, educators are looking for appropriate films running from 15 to 30 minutes. In fact, many will avoid the use of extremely short films simply because the time required to obtain and set up a movie projector cannot be justified for a few minutes of screen time.

Adult organizations, on the other hand, will normally shy away from film this long, preferring presentations that run less than 15 minutes.

Therefore, you should carefully evaluate the length of your film based on the target audience. You might even want to produce two different lengths (different versions) of the film to maximize usage for both the adult and the school audiences.

Professional Versus "Industrial" Talent

One of your responsibilities is to decide whether to use recognized (name) talent or unrecognized talent. There are advantages to using either type of talent (cost considerations and film impact).

The use of good industrial performers in place of name talent can result in an excellent film; for the most part, viewers are primarily concerned with the film's message.

If you decide to go with recognized talent, consider these potential (yet remote) conditions. An actor involved in your production could possibly do a film for a competitive company and create credibility problems. Or, such a personality might not be available when needed, could be too expensive, lose popularity, pass away, or even date a film.

On the other hand, there are certain films that require appropriate stars (films pertaining to major sports, such as skiing, bowling, auto racing, soccer, football, baseball).

Film Content

Film content must be a blend of what the client deems impormnt to get across to the public and the producer's interpretation of those aims. Some producers, unfortunately, make elaborate films strictly to win filmmaking awards and to gain recognition, the content and the cinematic techniques applied may be accentuated to that end. It is


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conceivable that the client's/sponsor's original purpose for the film has been somewhat misdirected. The real objective is to meet all of your client's expectations.


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WEDNESDAY, JULY 31

Distributor Services

The actual elements of film distribution are simple in theory but vastly more complex in practice. You might think that to successfully market your film you need only an audience and a method of getting the film to the viewers. However, distribution is really a more complex science.

Mass audiences, such as classroom students (kindergarten to college level), are fairly easy to locate. Other target audiences (skiers belonging to ski clubs and members of hunting and fishing Rod and Gun clubs) are not particularly hard to reach because they belong to well-known organizations. However, certain desired target audiences are difficult to find and perhaps not as easily influenced toward using your film.

This section, then, covers the advantages of using film distributors and the techniques they use to help you and your sponsor determine less obvious target audiences.

Promotional Ideas

Efficient promotion can heavily affect overall film distribution. To assist the sponsor, supplemental promo literature (ranging from a single handout to a series of brochures and catalogs) can be prepared by the distributor. Regardless of the format chosen and the cost of producing such a promotional unit, there will be an extra expense in getting materials to the audiences.

Obviously, a direct-mail system will play a vital role in getting promotional media to the film users; to help you, distributors have the latest comprehensive mailing lists of nationwide business and educational institutions.

The handling of promotional materials can range from self-mailers to elaborate catalogs. Costs for an outside vendor's services (layout and printing) are only part of the expenses that must be factored in; you may also be charged for mailing lists, handling, and postage.

Self-promotion by a sponsor who has a single film would cost more than any other unit listing several films for which promotional expenses could be amortized. The only time a distributor might charge the sponsor a special fee would be for a very unique promotion. If the sponsor's film is listed in general catalogs indicating numerous film availabilities, then there will not be a separate distributor's charge.

Print Inventory

Print inventory is virtually the key element in effective film distribution. The sponsor will need a sufficient number of prints on hand to adequately supply all of the intended target audiences. Unfortunately, many films are produced without consideration given to this subject. Frequently only a minimal budget is set aside for filmprinting costs.

Based on an old rule of thumb of approximately 20 different audience


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bookings per print per year. a sponsor can roughly calculate how many audiences can be reached in a year on varying print inventories and thus estimate the cost of such distribution including prints and commercial circulation.

Again, be sure you account for anticipated distribution costs in your planning and budgeting activities. Check with several film distributors concerning pricing for print-inventory services and factor those expenses into the distribution plan. It would be unfortunate for you to discover late in the game that sufficient dollars were not set aside for proper film distribution.

Supporting Materials

Besides considering print inventory and distribution cost, you should also think about the possible use of printed instructor or program chairperson materials, as well as student or group member take-home pieces. Far too many films are sent to audiences without adequate support information; by merely supplying a business leader' s (or teacher's) booklet or guide with the film, you can make it a much more appealing and meaningful package from the audience's standpoint.

Typical subjects include: a capsule description of the film, an in-depth discussion of the film's historical context, and a precise presentation on the products involved (including prices).

Other possible uses: hints on product features and usage, suggestions for discussion after the Screening, demonstration kits for teachers, tidal charts for fishermen, game laws for hunters, of exercise suggestions for athletes.

Film Maintenance

Finally, most film distributors will offer a print maintenance program. Under such an agreement, your prints will be completely inspected for torn or open splices, torn sprockets or other imperfections, scratches, and missing footage. Early correction of these problems will protect your prints from possible damage and loss.

The distributor will place protective, colored head and tail leaders (complete with the address of the distributor) on the release prints, because:

l You can easily identify the film by title and print number. l Color coding of the leader will immediately indicate if the print is

heads or tails out (to determine if rewinding is necessary). l The leader will indirectly guard against film loss through the mail,

in the event that the film and its case become separated. l The leader will protect the film from damages occurring by way of

improper projector threading. l The leader will clear the projector gate of dust and debris before

the film is projected.


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Documents

Film Making] - Cinematography - Kodak Student Filmmaker's Handbook