The Channel Mixer effect modifies a
color channel by using a mix of the current color channels. Use
this effect to make creative color adjustments not easily done with
the other color adjustment tools: Create high-quality grayscale
images by choosing the percentage contribution from each color channel,
create high-quality sepia-tone or other tinted images, and swap
or duplicate channels.
-
[output channel]-[input
channel]
-
The percentage of the input channel value to add to the output
channel value. For example, a Red-Green setting of 10 increases
the value of the red channel for each pixel by 10% of the value
of the green channel for that pixel. A Blue-Green setting of 100
and a Blue-Blue setting of 0 replaces the blue channel values with
the green channel values.
-
[output channel]-Const
-
The constant value (as a percentage) to add to the output
channel value. For example, a Red-Const setting of 100 saturates
the red channel for every pixel by adding 100% red.
- Monochrome
-
Uses the value of the red output channel for the red, green,
and blue output channels, creating a grayscale image.

Removing all Red input from the Red channel, and adding 50%
of the Green channel and 50% of the Blue channel to the Red channel