Adobe Photoshop Channel Mixer
The channel mixer can be accessed in Photoshop by going to Image> Adjustments> Channel Mixer. Depending on the files color profile, you will either have the CMYK (Cyan, Magenta, Yellow, and Black) or RGB (Red, Green, and Blue).
In this tutorial, we will use the RGB profile. The Channel Mixer is brought up with a drop-down for each output channel and the influence of each color on the specified channels.
I would like the image that I’m starting with to be a little warmer. We know that blues are cool and that reds are warm. So, to make the image warmer, we can take the red output channel, pump up the red, and bring the blue down just a bit.
In most cases, with photo editing, you can get a much more professional-looking effect by making a bunch of small changes rather than one or two drastic ones.
Create Black and White Photos with Channel Mixer
I find that I use a channel mixer most frequently as a dynamic way of turning normal photographs into Black and Whites. If you are just doing the effect of turning colors into black and white, there is a lot that you are missing out on.
Channel Mixer allows you to take those red, green, and blue channels and boost or pull back the levels of each one. In the photographs below, you can see that I’ve pulled back on the red and the blue and left green at a higher mark. The result is a softer image with lower contrast.
This may not be the effect that you wish for your photograph to have, but as you work with the channel mixer you will find it easier and easier to move the photograph from where it is to what you imagined it to be.
One GREAT site, you have gotten me into a new way to make saw dust Thank You I think LOL