Big_Hoovie. Interesting effect. I like it. Refraction inside a sphere seems like a way to go. Well I started building a lightdome still playing around with various types of lights. These are my Spotlight ones as viewed from the outside.(no sphere present) the arch render shows artifacts where the spotlights intersect. the dome render is missing about three rows of lights at the bottom. I'll use surface lights and radials next to see if 3.1 will support the idea of a dome any better using them. still catching up, - TJ