I know what you mean with the H-bomb effect, Iusually can't set the intesity past 25 or 30. To get more defined rays and shadows I click on the color tab above the intensity slider(usually black) and click the first shade below black. this seems to allow shadow definitions wp into the thousands. I've only had Luce for a few days now, ran across a link or mention of it here in the edit forum. I'll have to look again and see who posted it and thank them!

Thanks for the compliments!
