As thanks to PawelS and for all which want to use this fantastic tool, I do write an additional UGPM_ tutorial (some tips and fundamental description are in his UGPM_readme.txt, few examples are also contained). To make a good tutorial everyone can help with comments (question, suggestion…) here.

• I advise to use the (unfortunately old) GUI version (from HamletG).
  
• If you ready with your unit, use the latest original version (1.1 - 1.5 from PawelS) to create it.
  
• News thread here.
  

1. The first thing is, look and learn from other good coloring.
   
2. For “normal” coloring, you need only to change the RGB values.
   That means no change in contrast (or negative).
   
3. In most cases for “normal” coloring, the brightness is not to be change.
   That means the sum of someone (at best every, see below) RGB value must be 1.
   
4. If you want 100% details (colour information), every RGB value must be a sum of 1 (to high single negative value means also loosing a bit details).
   
5. The BRIGHTNESS (item command) isn't really necessary, but you can easy change all RGB values together.
   (That means BRIGHTNESS has the same effect as multiplying all the RGB values by the same number.)
   
6. (But) with CONTRAST you can do things that you can't do by using RGB of BRIGHTNESS, because CONTRAST is an exponential effect, not linear like RGB and BRIGHTNESS.