This video tutorial by Mabula explains how to
- remove light pollution and/or gradients in your color images with the “remove light-pollution” tool
- how to calibrate the background
- how to avoid surpressing faint colored nebulosity
- how to calibrate the star colors
- and finally, how to selectively adjust colors, in this case, we remove green cast, injected by the star color calibration. (You can also use the selective color tool to remove magenta and cyan edges at star borders for instance)
Data was shot with a 50mm f/1.8 Olympus Zuiko objective and a Canon EOS 450D by Scott Rosen.