I have a lightbulb, with an "area light" inside, and that works fine, spreading light ...

[pellepiano]

.... on the painting. But the colors of the bulb does not show at all on the painting. What am I missing ? ( I always miss basics =) )
I would like an end result more like the small example in the image.

 

[frank beckmann]

That should work: light source shadow set to Raytrace+trans and the lightbulb (add a shell-modifier for a small amount of glass thickness) got a dielectric shader with colors (Image or procedurals):

Cheers
Frank

 

[pellepiano]

Beautiful example, thanks. It was mainly the Shader type that made it work for me. So now I know something more about Cheetah and can experiment with idea and not how =)