There are times when you want your color to exactly match what's in the
scene, but for the most part color is a fairly subjective matter that can be
tweaked with ease in just about any image-editing program. Color has a hue--like
yellow, green or blue--as well as a vividness, which in photography is
often called its saturation. In addition, color can have a cast, which is influenced
by the prevailing lighting conditions when we make the photograph. That cast
can be influenced by the light source itself, such as photographing under direct
sun versus what we'd get when photographing under tungsten lights, and
by the position of the subject in relation to that light source, such as the
difference between photographing in the shade or open light. In addition, color
can also be influenced by the recording medium itself, be it film or digital,
and how the film is made or the digital image processor is programmed to change
the color during the recording processing.
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