Game Development Reference
Here's the way this one works. The name of the color on the left
refers to the input color (i.e. before applying the effect), and the
name of the color on the right refers to the output color (i.e. after
applying the effect).
Let's take for example the Red-Green property. By default, it's
set to 0, which means that there is no red (input) in the green
channel (output). But, if we raise this value to 100, then it would
add red to the green channel. When we add red to pure green (as
seen in the green star in this comp), it becomes yellow (Fig. 6.21).
Figure 6.21 After taking the Red-
Green value to 100, red is mixed
into the green channel, which
turns the green star yellow.
You'll notice in the Effect Controls panel that the properties
that are duplicates (e.g. Red-Red, Green-Green, Blue-Blue) and
are set at 100 by default. This only means that there is a full mea-
sure of red in the red channel, green in the green channel, and so
on. If we took the Red-Red value to 50, it would mean that there is
half of the amount of red in the red channel. Because the red star
only consists of pure red, when we take the Red-Red value down
halfway, in effect we reduce the intensity of the red in the red star
by half. Notice that the yellow (formerly green) star isn't affected,
even though it contains red. The Red-Red adjustment does not
affect the red in the green star because it didn't start out having
red; it was added by the effect (Fig. 6.22).
You can also use this effect to create an excellent black and
white result by selecting the Monochrome option at the bottom
of the Effect Controls panel. With Monochrome selected, you can
still control how colors are converted to black and white (i.e. their
brightness) by using the color sliders in the Channel Mixer's effect
options in the Effect Controls panel.