[vtkusers] Lighting and washed out colors

[Kevin Wright]

Can anyone tell me why, if I have diffuse lighting set to something 
non-zero, and I turn ambient lighting up to a non-zero number that the 
colors on my scalar-mapped surfaces start washing out?  Is this something 
intrinsic in OpenGL Lighting?  Can I work around it?

I would like to keep shading, while also having some ambient lighting for 
better visibility, but I can't afford to wash out the color mapping.

Any information would be appreciated.

Thanks,
Kevin.