BI Lighting Mystery: Ceiling is receiving less light than the rest of the room While testing out a lighting setup for archiviz in Blender Render I encountered a strange problem. The ceiling is too dark no matter what I try.



Here are some things I tried:


Checked that normals are facing the right directions
Removed all modifiers from ceiling plane object
Joined ceiling and room as a seamless mesh
Tweaked all lighting settings I could think of
Tweaked all material settings I could think of
Extruded the ceiling plane to give it a volume


Things to note: The only light sources are a duplivert array of Point Lamps and the ambient light from outside the room. I tried other types of lamps such as Spot and Area, but settled on Point because I found that the shadows looked best with Point. The other lamp types still didn't brighten the ceiling enough, except when I created a dedicated secondary Area Lamp pointed upward at the ceiling - which caused lighting problems in other parts of the room because the undersides of furniture would glow.

I made a special material for the ceiling that is like the rest of the room, except with some emission to brighten it. It looks better with that on than the regular room material, but doesn't look good because it kills the shadows in the corners. And besides, it's a hack and doesn't solve the real problem.

What could possibly make a ceiling appear darker than the walls it touches?
Well your using Blender internal and not cycles so its not perfectly light emulation. Here are the steps to make it a bit better, first decrease the strength of those lamps 

( set it to 0.001 or so, there is way to much light in the scene currently).

in the world tab:


enable Ambiant Occlusion
enable indirect lightning
set Gather to Approximate


there are some more problems (placing of lights etc) but above should give you a start for this file.