Quote Originally Posted by michael stevens View Post
Presumably if your darkroom was painted red you wouldn't need safelights at all. As long as all the light was being bounced off the walls and none spilled directly from the lamps.
I would think that paint surface, even a full, deep red colour, would reflect much broader wavelengths than just the red that we think we see. Even a red filter ( not a Kodak or similar safelight filter) over a standard lightbulb (with the possible exception of rubylith) probably transmits plenty of other wavelengths, and is not really all that safe for much more than a few minutes' exposure.