Hi, I'm a newbie right here and fall in love with Paint.Net after using it for several time.
Beginning my posting with a tutorial on how to create a contrast mask. thisisatutorial
Link to tutorial : http://www.gimp.org/tutorials/ContrastMask/
Intended program: GIMP
Plugins needed and notes : All included inside this blog post
( http://isminailofar.wordpress.com/2014/06/16/contrast-mask/ )