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Re: triton reflectors or the like
George Booth's comments on just doing your own "ray tracing" with a simple
sheet of graph paper are very sensible, but I wanted to add a little more for
the over-achievers out there that feel they have to have the "best" reflectors.
Someone a while back mentioned using a shape "much like a McDonald's M" on
each individual bulb, the middle point of the M right above the bulb itself to
immediately reflect out all the light behind the bulb. I apologize to the
author, since I can't remember who it was and I don't have the energy to go
search the archives.
The M shape might work better than a parabolic shape because bulbs give off a
TUBE of light rather than a line. The coating on the inside of the bulbs is
what gives off the light -- stare at a bulb to see that in fact the edges of
the bulb give off as much light as the middle of the bulb (well...not really,
but I won't go into it). We ignore it because if the reflector is far enough
away from the bulb relative to its radius, it doesn't make a difference.
If you follow George's advice on ray tracing, you can get closer to the "true"
reflections by drawing light rays in all directions coming from equidistant
points along the tube's perimeter (on a cross-section graph), rather than just
drawing lines from the center.
Again, this is over-achieving and having a dirty tank cover will make a MUCH
bigger difference than whether the light is a line or a tube. However, one
day I'll be bored and I'll write a little C-program that will show me the
light rays hitting the surface of the water for any chosen reflector shape.