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7/24/2019 Understanding Photography
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SUBTLE NUANCES OF BETTER PHOTOGRAPHY: UNDERSTANDING YOUR CAMERA
I am sure each one of us would have, at one point of time at least, taken a photograph of someone or
something which we wish to capture and relive at some date in future. While the instrument used for
capturing images has been widened to include cell phones, music players and even a pen, the primary
device still remains the good old camera. Most of us just point at an object and shoot it in the auto mode.
This doesnt require any expertise and its just by stroke of luck that the image captured turns out to be a
good one. Even a small child can point and shoot. So, the objective of this article is to help you take controlby demystifying some nuances of your camera with the aim of helping you capture images nearest to what
you actually saw with your eyes.
Camera Basics
Let me first start with the camera basics. These days, when we speak of camera, most of us are obsessed
with one term megapixels (MP). The common (mis)understanding being higher the MP better is the
camera. This to me is just a marketing gimmick and far from truth more so cos I am sure most of us
would be blank if someone were to ask uswhat does MP denote resolution ofis it of the LCD screen of
the camera? To answer this, let me unravel what truth actually is and also make an attempt to demystify a
few other concepts that would help you become an informed photographer. However, the underlying
objective of this article would be to help you take control of your camera beyond the auto settings so that
you can capture better and more creative images.
The main components of a camera are the lens and image
sensor. Inside your camera, there is a mirror (2) that reflects the
image coming through the lens (1) up to the camera's viewfinder
(3). When you put your eye up to the viewfinder you see exactly
what the lens sees. When you take a picture, the mirror flips up
out of the way of the shutter (4) that sits directly behind it. The
shutter opens for a brief period of time to expose the digital
image sensor (5) behind it to the light passing through the lens.
It is the resolution of this image sensor that is measured bymegapixels. Once the picture has been taken, the shutter closes
and the mirror flips back down again. This entire sequence of events typically takes only a fraction of a
second.
Let me explain a bit about the image sensor. The sensor consists of an array of "pixels" collecting photons,
the minute energy packets of light. The number of photons collected in each pixel is converted into an
electrical charge and through a whole lot of process and finally into a digital image. In the single-lens reflex
(SLR) camera the photographer sees the scene through the camera lens. This avoids the problem of parallax
which occurs in point and shoot (compact) cameras. Digital compact cameras have substantially smaller
sensor size offering a similar number of pixels. As a consequence, the pixels are much smaller, which is a
key reason for the image quality difference, especially in terms of noise and dynamic range.
Having understood the mechanics of capturing an image, let me take you to the artistry of photography.
The amount of light entering a camera (i.e. exposure) is the defining feature of how good (or bad) your
image will turn out to be. The other significant factor is the focus of your subject. Together, these two
decide the composition of your final image. In this article I shall talk about exposure.
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Exposure
There are three ways of controlling the amount of light which is captured by the sensor through
adjustments in the aperture value, shutter speed and the ISO level. These are all measured using different
units, so the concept of "stops" was invented as a convenient way to compare them.
Aperturerefers to the size of the opening in the lens that determines the amount of light falling onto the
image sensor. The size of the opening is controlled by an adjustable diaphragm in the camera lens. Aperturesize is usually calibrated in f-numbers or f-stopsthe ratio of focal length to effective aperture diameter. A
lens typically has a set of marked "f-stops" that the f-number can be set to like f/11, f/8.0, f/5.6, f/4.0, f/2.8
etc. These are engraved on the lens barrel of any camera. A lower f-number denotes a greater aperture
opening which allows more light to reach the image sensor. Thus f/8 will let in half the amount of light than
a diaphragm opening of f/5.6 while on the other hand, an aperture of f/2.8 will let in twice the amount of
light than f/4 etc.
Aperture affects exposure and depth of field (DOF). Depth of field is a term which refers to the areas of the
photograph both in front and behind the main focus point which remain "sharp" (in focus). DOF is affected
by the aperture, subject distance and focal length. A larger aperture (smaller f-number, e.g. f/2) has a
shallow DOF. Anything behind or in front of the main focus point will appear blurred. A smaller aperture
(larger f-number, e.g. f/5.6) has a greater DOF. Objects within a certain range behind or in front of the mainfocus point will also appear sharp. The images here would serve to highlight my point. Adjusting the
aperture and the resultant DOF can help you take nice portraits with the subject in sharp focus while the
background is blurred.
Photo 1: At a large aperture of f/2.4 only the first card is in focus, while at f/8 the middle card is sharp and the distant card is
almost as shar .
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Changes in aperture result in changes to shutter speed. Simply put, you cannot change one of these
settings without having to change the other to compensate, i.e. higher the aperture value (f-stop) the
slower the shutter speed needs to be. In its most basic form, the definition of shutter speed is pretty
simple: it is the amount of time (measured in fractions of seconds) that the camera's shutter stays open to
allow the light to be captured by the image sensor. The period of time that the shutter remains open is
something you can control.The vast majority of shutter speeds that you will use are fractions of a second
(for example: 1/60thof a second) and are displayed as the bottom number of the fraction, for e.g. 1/1000 th
of a second will be displayed as 1000 etc.
Let me now provide instances where adjustments in shutter speed could deliver desired results. The first
thing that comes to my mind is during night photography where reducing the shutter speed to 1 second
and above can allow images to be captured even without the use of a flash. The flip part here is that such
photography is best done with the camera absolutely still, essentially entailing the use of a tripod. Adjusting
the shutter speeds to slower levels can help you capture the trails of the stars on a clear night sky or the
trials of lights of moving vehicles. The key thing to remember about using a slow shutter speed is that
anything that moves in the scene will blur but anything stationary will stay in focus. Once you're aware of
this you can use it creatively in your photography.
ISO value describes how sensitive your camera's image sensor is to the light that falls on it. A more
sensitive sensor will produce the same overall exposure from less light, meaning that you can use anarrower aperture or faster shutter speed in the same conditions. A higher ISO number relates to a more
sensitive sensor. As with shutter speed, doubling the ISO number gives an increase of 1 stop, while halving
gives it a decrease of 1 stop. For example, switching from ISO 100 to ISO 200 doubles the sensor's
sensitivity, producing a 1 stop increase. If you are setting the ISO manually, here is a basic guide: 100 ISO in
bright sunlight; 400 ISO on a dull, dreary day; 800 ISO for indoors under floodlights; generally speaking, the
higher the ISO, the lower the picture quality (noisier image).
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When adjusting the three components of exposure you should be aware that each one affects your photos
in other ways, which may not always be desirable. A wide aperture produces a shallow DOF, so if you make
it too wide you may have trouble keeping everything in focus. On the other hand, a shallow DOF can help to
isolate the subject, and is often something that you want. If your shutter speed is too slow your photo may
blur, either from movement of the camera or movement of the subject. The more you increase your
camera's ISO, the more digital noise your photos will exhibit. This can make your image look grainy and
reduce its sharpness. Adjusting these three settings is a balancing act. You need to decide what effects you
want in your shot and choose settings that will produce them while minimising the potential shortcomings.
Exposure stops are a really useful tool for doing this, helping you swap settings around with ease and giving
you more control over your scene
Some Creative Photo Techniques: Using the aforementioned concepts
1. Portraits: Portrait photography delivers best results when you focus attention on the subject and
control the background. Avoiding distracting elements or blurring the background draws the attention on
your subject. Besides making your subject the star of the frame you also need proper exposure and focus,
showing right skin tones and details. Switch your camera to Aperture Priority mode by turning the mode
dial to A (Av on Canon models). Stand back a little and zoom-in your lensthis will accentuate the effect.
Choose the smallest f-number thats available so as to narrow the DOF. To further highlight the effect,
increase the distance between the subject and the background. So keep the person relatively close to youfor a head and shoulders shot, and position them against distant background.
2.
Motion Blur: For example capturing a motion blur by panning your camera with a moving target. If the
subject is moving, as is the bike seen in the picture, move the camera to follow the subject and keep it
sharp while blurring the background using a slow shutter speed. Try different shutter speeds to balance the
Photo 2: I clicked this pic with my camcorder (Canon Vixia HV 30) which a relatively low image resolution (3.1 MP)at the maximum available aperture value (F/2.8) and with manual focus at focal length of 23 mm to create ashallow DOF. The background thus does not compete for attention with the main subject, avoiding any distractionfor the viewer.
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background blur you want against subject blur you don't want try 1/125 second to start. Keep your body
and the camera as steady as possible, track the subject through the viewfinder and ensure your camera is
focusing properly on the subject, and take the photo. This technique uses the blurred background to
highlight the motion of the subject, whereas background blurred solely through a shallow DOF is used to
make the subject stand out from its surroundings.
3. Sunset: The colours during sunrise and sunset can look spectacular with our eyes, but prove surprisingly
tricky to capture with your camera. If you let your camera decide what exposure to shoot at then youre
likely to get a shot that doesnt really capture the beauty of the light. Instead of relying upon the cameras
auto mode, a sunset is an ideal time to switch your camera into aperture or shutter priority mode and to
take a variety of shots at different exposures. The great thing about sunsets and sunrises is that there is no
one right exposure and that you can get stunning results using a variety of them. Also keep in mind that
different exposures (aperture value and shutter speeds) will produce a variety of different results so its
worth taking more than just a few shots the key is to experiment. I tend to switch into shutter prioritymode and start with a relatively quick shutter speed and then slowly work down to slower ones. In this
photo I have deliberately underexposed the photo using the cameras exposure compensation settings.In
addition, the sensitivity has been increased from ISO 200 to 800. This has produced a far more desirable
result with deeper colours (a dash of orange), mild reflection of the sun on the thin layer of water on the
sand and darker silhouettes of people in the foreground.
Photo 3: I took this shot from my balcony facing the Western Express highway. The shutter speed was 1/15second with maximum aperture (of f 3.5) at the focal length of 38.5 mm with camera panned towards the right tocreate a nice motion blur capturing the speed
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4. Nature: Photographing nature entails more skill than simply pointing and shooting a camera.
Understanding your subject and your camera is crucial to taking exquisite nature shots. Being familiar with
your cameras settings will help you determine which setting works best for various typesof nature photos.
The idea is to take several photographs of your subject while changing shutter speeds and f-stops. This will
create different versions of your subject, instead of only one image. The more you experiment with this, the
better feel you will get for it. In addition, if the background is bright, try using the metering mode at spot
instead of evaluative or centre weighted and use focus lock and then recompose your shot with the
subject at the right place.
Photo 4: This is a shot taken at Aksa beach, Mumbai with ISO setting of 800, exposure compensation of -1 EV andcustomized white balance at a warm colour temperature
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5. Close ups (macro): In macro photography you will probably want a shallow depth of field so select the
largest aperture available. In macro photography, it is also helpful to have full control over focusing
especially when you have shallow depth of fields where it is all the more important to make sure the right
part of your shot is in focus. If your camera allows manual focusing select this option and manually focus on
the part of the subject that is the main point of interest. When shooting macro with a digital compact
camera always use the LCD screen for viewing never use the optical viewfinder. Use the optical finder
and you will encounter parallax errorwhat you see in the finder is not what the camera will photograph.
Photo 5: I took this snap at telephoto (focal length of 86.4 mm) at the maximum available aperture to create a
shallow DOF. Spot metering mode was used for focusing to separate the subject from the well lit background
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The Last Words
This article was just intended to be a primer. There are a whole lot of other interesting compositions and
creativity that you can achieve with your camera, especially if the camera allows you more manual control. I
hope that this article was able to achieve its desired objective, at least to a large extent. At the end of it all,
to help you understand your camera and as a corollary enable you to capture lifelike images, there is
nothing better than the user manual. Let that become a bible of your photography to which you keep
referring to regularly. Happy clicking.
Ashish Kumar
Photo 7: This close up was shot in macro mode at afocal length of mere 5 mm, again with manual focusand aperture of F/2.8. Look how the background is
totally out of focus making the subject appear the only
point of attraction
Photo 6: I used a tripod for this close up, shot in macromode at a focal length of 8 mm with manual focus and
aperture of F/2.8