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To introduce Digital Photography Explain the advantage of using a Digital
Camera Give an overview on what is going on
inside of your camera Help you get acquainted with the
different camera modes on your camera Get you ready to begin taking
photographs
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Digital camera: A camera that captures the photo not on film, but in an electronic imaging sensor that takes the place of film.
Two popular types of cameras on the market for the consumer
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Point-and-shoot
SLR (Single-lens Reflex)
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Point-and-shoot Viewfinder separate
from lens Small and compact Fixed lens Shutter delay Usually fully automatic
(some exceptions, like Olympus C-series)
SLR (Single-lens Reflex) Based on 35mm design Actual image seen in viewfinder Interchangeable lenses (more
flexible composition) Ability to use filters More advanced metering and
shutter system Little to no shutter delay Automatic, Program (“Scene”),
Shutter Priority, Aperture Priority and Manual modes
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Viewfinder separate from lens (better to use LCD on digital) Actual image (as exposed) is not quite the same as in the viewfinder Much simpler design than SLRs.
Light Path
Lens
Camera Body
Viewfinder
(front)
Shutter
Sensor or Film
Viewfinder
Focal Length
LCD Screen(Digital)
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Through-the-lens (TTL) viewing (works like a periscope) Actual image (as exposed) is shown in the viewfinder Mirror flips up when the shutter release is pressed, exposing the
sensor (and blacking out the viewfinder) “Reflex” comes from the use of the mirrors in the viewfinder system.
Light Path
Lens
Camera Body
Focusing Screen
Mirror (Pentaprism)
Mirror (flips up)
Shutter
Sensor or Film
Viewfinder
Focal Length
LCD Screen(Digital)
Instant gratification – see your images right away No film cost – shoot as many as you want, erase and
shoot again Convenience – print, email, web, slide shows; no waiting
around for the photos to come back from the store Easier to make copies – no need to send (or lose) originals Easier to manipulate – no scanning No need to spend hours in the darkroom (although its
fun!) No worries about film fading over time; digital images last
for as long as your storage media doesn’t die on you Less storage space – no physical shelves to keep stacking
Image quality Skilled user needed to extract the image quality equivalent to that of good
film As good or better than 35mm in the right hands, but cannot compete with
medium or large format film (yet) Blown highlights – no information means no information; film is better at
rendering overexposed areas more naturally
Very different workflow – requires skill with computers and software, knowledge of color management and printing, web, email, etc.
You are the photo lab – you’ve traded darkroom chemicals for a digital darkroom
Easy to lose images – memory cards can become corrupted in-camera; photos are scattered all over your computer; hard drives die
Shutter delay (point-and-shoot) Digicams are much more expensive than film cameras and become obsolete
sooner More megapixels = bigger files = more storage + faster computers
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The apple or the orange?
Each has their respective strengths and weaknesses.
It all depends on what you’re trying to accomplish.
Everything in photography is a trade-off.
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With Digital photography:
The “film” in a digital camera is a light sensoro When a photo is taken, the Light Sensor (CCD):
• is struck by light coming through the camera's lens• converts light into thousands [or millions] of pixels
oDEFINITION: The CCD is the light-sensing device inside a digital camera and is composed of an array of individual sensors, or pixels, that "see" the image coming in through the camera's lens.
o Each pixel (or tiny ‘dot’ on the CCD’s surface) stores color/light data.
* All this occurs at single moment when shutter opens and closes
• Pixel (Picture Element): digital photographs are comprised of thousands or millions of them; they are the building blocks of a digital photo.
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Here is very simple pictorial representation of a ‘CCD’ in action.
This ‘CCD’ has a resolution of (12 x 12) 144 pixels. Each dot that makes
up the man is 1 ‘Pixel’.Because the ‘resolution’ is so low the
image has very limited detail.
Back
•The image Resolution: tells us the total numberof pixels than an image contains.
• This number is usually expressed in terms of "megapixels" or how many million pixels a camera can record in a single image.
•This resolution number is found by multiplying the height x width in pixels.
•Megapixel: 1 million pixels
A camera that captures 1600 x 1200 pixels produces an image with a resolution of 1.92 million pixels and would be referred to as a 2.0 megapixel camera.
A 4.0 megapixel (or higher) can output an acceptable 8 x 10 inch printed image 4 MP cameras have 2,289 x 1,712 pixels
200 DPI image is 11.4” x 8.6” 14 MP cameras have 4,500 x 3112 pixels .
(You get to 1.92 million pixels by multiplying the vertical and horizontal dimensions. That number is then rounded off to 2 for marketing purposes.)
More resolution means better quality - up to a point.
The higher the resolution, the sharper the
picture.
• Your camera should have a setting which will allow you to change the final photos physical size & also its resolution.
• To print out a photo to a decent quality or to a large size a high resolution is required. This will make the file size of the image larger.
• If you start off with a high resolution picture it is easy to remove pixels (ie lessen the resolution)
• If you start off with a low resolution picture it is harder (near impossible) to add more pixels and keep the quality high
Resolution DPI – dots per inch The measurement of resolution of display, printing, and capture
systems. As the “dot” (or pixel) rate doubles, the number of dots quadruples.
100 dpi = 100 x 100 = 10,000 dots/pixels per inch 200 dpi = 200 x 200 = 40,000 dots/pixels per inch
Different output devices require different resolution: Computer screens display at 72 dpi, although software may zoom
in Print devices print no higher than 300 dpi
Human eye cannot discern more than 300 dpi without magnifier
http://photo.net/equipment/digital/basics/index?&for_print=1 Digital Camera
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•The advantage of having a camera with a higher resolution is you have more pixels to work with.
•That's important when getting prints made. In general more resolution means better print quality. It also gives you an advantage if you need to crop the image.
•Cropping: is when you only use part of the image for the final print. It also gives you an advantage when creating larger 5x7, 8x10, or bigger prints.
•The more you have to blow an image up the more any defects will start to jump out. Starting with a higher resolution image means there's less magnification necessary to get to a given print size.
•As you can see, the 4 and 5 megapixel photos are much larger than the 1 and 2 megapixel photos allowing for much greater detail in your prints and giving you the ability to crop, or "cut off", parts of the photo while still retaining enough pixels for a good print.
•Remember, the more you have to blow it up the more you degrade the quality.
……how it happened:how it happened:
•It all started with NASA•One of the uses of these satellites was to spy on the enemy – 1959-1972 •Beaming photographs back to Earth, using ‘Digital Technology’.
The ‘Charge-Coupled-Device’, (or CCD) was first demonstrated by Bell Laboratories in 1969 as a way to store data
In 1975,the first CCD TV cameras were ready for use in commercial broadcasts.
In 1979, an RCA 320x512 Liquid Nitrogen cooled CCD system saw first light on a 1-meter telescope at Kitt Peak National Observatory.
•The first images created with CCDs were only 100 x 100 pixels – not very clear •The next goal was to create a better picture, which they successfully did in 1978 with a pixel array of 500 x 500•Soon after they’d developed 800 x 800 pixels, with a progression towards the development in 1982 of 1024 x 1024 pixels. The results were always a better picture, at a more affordable price
Optical zoom lenses actually “move” you closer to the subject of the photograph without sacrificing quality.
The higher the optical zoom rating on a camera, the farther away you can be to take a photograph and still get a clear, close-up image.
The concept of optical zoom essentially the same as the zoom on a film camera.
Optical zoom is the number you want to pay close attention to--it’s the zoom that will give you the quality results you want.
Digital zoom on the other hand is not bringing you closer to the item.
The camera crops the entire image, and then digitally enlarges to the size of the viewfinder the portion you want to zoom in on.
This results in a loss of quality, and is no different than cropping and enlarging an image with editing software.
When you use digital zoom on the camera, the image quality is irreversibly lost.
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Video. Digital cameras can capture video. Get a large storage card (2 or 4GB’s) to give you enough recording time.
Macro/Close-Up. This mode is used for taking close-up pictures.
Night Time. Sets longer exposures to capture darker scenes. Usually used with flash, and some nice motion effects can be created.
Portrait. To attempt to blur out the background the camera will try to use the fastest available lens setting (aperture).
Landscape. The camera will attempt to capture detail in foreground and background by using high f-stop (aperture) settings.
Sports. To freeze motion the camera will use the highest shutter speed possible.
Stitch. For creating multi-shot panoramas. This mode will help to combine several shots into one wide scene.
If you can’t control aperture or shutter speed directly, most point and shoot cameras offer scene modes (also available on advanced cameras and even SLRs)
Scene modes optimize the three factors of the Exposure Triangle – aperture, shutter speed, and ISO – for a particular shooting situation
Selects wide aperture to minimize zone of sharpness
Makes sharp subject stand out from blurred background
Works best on single subject (person, pet, flower, etc.)
Adjusts focusing distance and lets you move closer into your subject
Generally wide aperture for narrow zone of sharpness
Opposite of Portrait mode, selects small aperture for wide zone of sharpness
Use for wide scenes with more than one point of interest at different distances
Selects faster shutter speeds to freeze action
Usually selects wider apertures and higher ISO to compensate for faster shutter speed
Use any time you have a moving subject
Uses a combination of flash and slow shutter speed to equally expose subject and background
Use a tripod for a sharp background
Hand-holding can lead to some creative effects
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Coffee
The cameras internal menu
gives you access to
many important
adjustments…
…Image size & resolution, WB, ISO, and creative settings
http://www.slideshare.net/alexandracopley/digital-photography-introduction
http://www.slideshare.net/egore/digital-camera-basics-ncla-workshop?src=related_normal&rel=1856963
http://www.slideshare.net/ArrowQuick/intro-to-digital-photography
http://www.slideshare.net/cosmicandy/beginners-camera-course-show-2009?src=related_normal&rel=3734168
http://www.slideshare.net/quietheart/Basics-of-Digital-Photography-1077972
http://www.slideshare.net/peterliu47/digital-photography-i http://www.vividlight.com/articles/3116.htm http://dailyitech.com capitol-college.edu
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