Using the settings from THIS site, I applied different filters to the same image using the channel mixer. His settings and explanations are pretty good. It helps to see the changes each one does. Original color: No filter: Red filter: Green filter: Blue filter: Yellow filter: Orange filter: Yellow-Green filter: Hi Contrast: I didn't do any other PP to these images, just the suggested settings. I am hoping someone else finds it interesting and does some experimenting.