*You're doing nothing wrong. This is how real light behaves. This is a real life sphere with a point light, and the line between light and shadow is very harsh. It only looks odd to us because we rarely see any object lit from a single direction, there is almost always indirect light in addition.

*I did some testrenders again today and came to same conclusion, funny enough the moon was also the first thing that came to my mind. There are lot of things that are clear to me now. If I want to work with GC I have to lower my light levels, BB was absolutely right about that and he deserves credit for that and all his investigations, I'm just not a person who is easily convinced and have to try out things before I can accept it, but what's wrong with double checking?
Just switching on GC in poserpro isn't a solution to make your renders better. You also have to change the lighting and the shaders. In combination with GC, IBL is almost a must to use. It just enlightens the dark side of the moon
I'm afraid my dynamic hair shader approach wasn't a solution at all so I have reïnvestigate the hairshader  how I can make it work with Gamma correction. So I won't post my materialroomsettings, because it doesn't fix the problem. (excuse for that)
If anyone is interested I can post my GC testrenders.

Best regards,

Bopper.

-How can you improve things when you don't make mistakes?