The Channel Mixer in Photoshop is often overlooked. But in the hands of someone who knows what to do with it, it can be awesome. It can be used to change colors or for color grading. It can help you create color contrast. It can be a great way to convert to black and white. Combine it with a Curve and you’ve got a powerful tool indeed…IF you can figure out a way of reliably getting what you want. I’ll show you how to tame it in part one of this two part series.
Source: Photoshop Channel Mixer Madness!