Excellent responces!! I do lighthouse renderings as a hobbie and have had all sorts of problems with most any type of "long term" lighthing. That's the "Key". Any lighting, even indirect, should be somewhat limited in duration. Any lighthing that contains UV rays, such as sun-light or floresents should have limited exposure. A good rule of thumb....the closer that the light is located (in relation to the colour pigments)...and....the longer it is exposed, the more rapidly the colour breakdown occurs.