Color Management and Why We Need It - Color Management for Photographers - page 11

Fig. 1-3 Photoshop allows users to view a full color composite image or the individual color channels that make up the composite as seen
here. The channels are really Grayscale data—one for red, green, and blue—and when viewed together, a full color image can be produced
as seen in the window in the lower right of Fig. 1-3. Notice the three Grayscale channels in the Channels palette.
What Is Light, What Is Color?
In order for us to perceive the color of an object we need light to illu-
minate that object, and of course we need an observer (you or me) to
see the object. It may seem like a rhetorical suggestion but imagine how
the color of a red apple would appear in a room that is pitch black. Light
and color is an important ingredient of photography, color management,
and color theory. It's worth discussing in detail and (forgive me for
saying), looking at in a new light.
Light is a form electromagnetic radiation (energy) (see Fig. 1-5). One
way to look at electromagnetic energy is as a wave. The waves frequency