There is a bug in POV-Ray version 3.02  (Win95 version).

When rendering scenes with radiosity the "brightness" setting will
default to 3.3 during a pixel-by-pixel trace.  During 2x2 traces, 4x4
traces, and etc, the brightness value specified in the scene file
gives the appropriate results, as soon as a 1x1 is reached, the value
will default back to 3.3

THIS IS NOT A MINOR PROBLEM.   Brightness is the most important
setting in POV-Ray's radiosity.  To get around it, I've had to use
light sources with colour-components greater than 1.0  This trick
ruins the scene where there is direct lighting and can never match the
results of higher brightness values no matter how much larger the
light's components are made.

This bug happens even if I repeat the "brightness" statement
continually in the scene file. Even after a restart of POV-Ray.  Even
after saving the scene. Even after rebooting. With or without
anti-alaising. With or without global ambience, with or without
assumed_gamma.  Even after closing all other programs and
re-rendering.

To see this problem in action, set the brightness to some ridiculous
value (around 55.0 or so).. The first pass of the scene, usually an
8x8, the scene will be washed-out in glowing white, then during the 
final pixel-by-pixel pass, the rendered lines should look noticably
darker. In fact, just as dark as they would be for a 3.3 brightness!!
This has happened at a myriad of brightness settings above 3.3

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