Boot Camp 5: Channel Mixer

The Channel Mixer is a helpful tool when creating grayscale images from color images, or adding a tint to color images.
Here is a basic guide for getting started:
GUIDE

Also, check out these videos

This is what the channel mixer panel looks like!
Here the colors are in RGB mode, in CMYK mode they would read cyan, magenta, yellow and black instead of red, green and blue.
These are the “source” color channels, and mixing them informs the appearance of the “output” color channel.