Getting a nice vibrant picture with Gothic 2?

I've just installed Gothic 2 and have been playing around a bit, and I just remembered how dull the picture is. I seem to remember years ago when I first played it I managed to get a much more vibrant picture with a specific combination of Brightness, Contrast and Gamma. This time though I can't seem to get it, and I can't remember exactly what I did.

So I was wondering if other gamers have played around with these settings and if you have can you tell me what you did? Or do you just tend to leave them as they are?

Thanks very much.