Instruction manual

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Sometimes you take a photo of a black image, but upon review you notice the
camera rendered it more grayish. By underexposing the photo, you can restore
the blacks in the image. Conversely, if you take a photo of something white (such
as snow) and it appears grayish in the photo, you can overexpose the image to
restore the whites.
When the camera's metering system determines the wrong EV needed to
correctly expose the image, you can correct it by using the "EV Compensation"
feature (found in higher-end cameras such as the Nikon D200). Typically the EV
compensation lets you specify an amount of over- or under-exposure in steps of
½ or ⅓ stops (0.5 or 0.3 EV), and allow you to over- or under-expose by up to two
stops (-2.0 EV to +2.0 EV), while some Digital Single Lens Reflex (DSLR)
cameras have wider EV compensation ranges such as -5.0 EV to +5.0 EV.
It is important to understand that increasing the EV compensation by 1 is
equivalent to reducing EV by 1 and will therefore double the amount of light. To
use this feature, decide whether the image needs over- or under-exposure. When
the main subject is darker than a bright background, use a positive (+) exposure
value; if the subject is much lighter than the background, use a negative (-)
exposure value.
For example, when you need to use the EV control to underexpose a shot (as
when you’re taking a picture of a target resting on fresh, bright snow or when the
scene is lit with strong sunlight), try using an EV between 0 to +2. If you are
taking a photo just before sunset, you might try to overexpose the image by using
an EV between -1⅓ to -⅔.
Bracketing
Bracketing is a process where you shoot extra photos above and below your
target exposure. The easiest way to bracket is with your EV control: take a shot,
dial in an underexposure and take another shot, then do the same with
overexposure. Many cameras (such as the Nikon D200) have an “auto
bracketing” feature where the camera does the setting for you. For example, the
D200 Auto Exposure (AE) lets you set the number of shots you want to take (e.g.,
3); when you press the shutter the camera shoots the image with normal
metering, and then automatically adjusts for one stop of overexposure. This
setting is used for the next shot, while the shot after that will automatically be set
for one stop of underexposure. [If you activate the camera’s burst mode, simply
press and hold the shutter release for three shots, and the camera will shoot an
auto bracketed set.]
2.5 White Balance
White Balance (WB) is nothing more than an adjustment to get the colors you
want. White balance only adjusts far enough to make lights that look white to us
look white in photos. Most of the time you have the camera set for Automatic
White Balance (AUTO or AWB). Fortunately, digital cameras even make
manually setting WB easy; you just set the white balance to look good on the
color LCD.
Different light sources have different color temperatures, so a photo will
appear to have a slightly different color tone depending on how it is illuminated.
The color of artificial light is quite different from natural outdoor light. For example