You might also find a book on stage or film lighting at a half price tpye book store. The problem with Poser (at least v. 3) is that with 3 light sources, there's not a lot you can do, and as far as I know gels are completely out. Basic lighting theory says that you have a key light, which is your main light, and a fill light, which should be shifted into the complimentary color of the key light. In other words, if your key light is yellowish, your fill light should be bluish. This technique can be found in paintings going back to the Renaissance. If you have a white key light, then your fill should be a slightly bluish grey, because the human eye tends to perceive warm colors over cooler ones, and presented with white will always shift it slightly toward red or yellow in the brain. Also, I've found that if you pick a neutral (grey) as the highlight color in the poser renderer you loose some of the orange cast of the figures.