I wonder if you mean....taking a solid object, putting a material on it, then converting it to a light? This is much the same as I did above, just slightly different. i did this by creating a sphere, placing a material on it, converting it to a light (you do that with the little arrows up in the top left of the Edit window), then tweaking the material and strength of the light until I got the effect I wanted. Sun turned off, atmosphere turned off, sky colour black. I placed plane behind the light so that it would show. You can have the light object either visible or invisible. This anything like the info you're searching for?