Quote Originally Posted by another view
I prefer the channel mixer technique, the main thing is to keep the levels adding up to 100%. I usually do this before levels; using levels as a final touch to boost the contrast a little. As far as what numbers to use for the R, G & B channels, it's just experimentation.
To add to what Steve said, it really depends on your image as to which channels get what settings. There can't be a single setting to cover all images. It has a lot to do with your color balance.

Here's a link that says what Steve said, but with photo examples.

http://luminous-landscape.com/tutori...w_better.shtml