i was using a tut on radiosity to figure it out, and it was going through the process but after it had finished i don’t know how to save the image. If i render it, i get a black screen unless i put a lamp in, and then it just looks normal. How do i save the proper radiosity image?
When Radiosity calculation is over you must press the ‘Replace Meshes’ button far right and the the ‘Free radio data’ button nearby.
Then you can render 
Stefano