Looking through lighting folder for the word "Voltarc" (for which
thanks to Thaddeus), I came across two items. First, the fluorescent
bulbs are rated for nine thousand (not two thousand) hours. Output does
diminish, but gradually.
Second, I have some typed notes made years ago after a conversation with
Sylvania about a "par 38 mercury lamp." This my notes say gives a cone of
light, uses 100 watts, costs $45 plus $50 for the black box ballast
(10-year old prices), runs
16,000 hours, looks like a flood lamp, gives radiation about the same as
a sun lamp & about as much light. Since then I haven't come across the
bulb that I know of. Does anyone know more about this bulb? If it's
still made, sounds like a better bet than a sunlamp. (But with any "cone
of light" source, be sure to test the perimeter exposure against the
center exposure for fall-off. )
Also a couple of afterthoughts on plateburners. If you do get an offer
you can't refuse, be sure the model has vacuum bleed. The normal vacuum
(about 25 lbs psi) crumples your paper. Also, the kind that inverts gives
the worst of both worlds -- all the disadvantages of a plateburner and no
possibility of dodge and burn. (I do both with the NuArc, wearing
UV-proof sunglasses.)
And for safety generally: I have a 1982 brochure from Westinghouse that
says "contrary to popular belief UV light is not harmful to humans." Of
course last year Phillips, which bought Westinghouse, said the equivalent
of "YIKES!!!!! We said that!!!!????" It's interesting, however, that when
pressed, the man said frankly we really don't know about the harm of UV
rays to the eyes, and reading between the lines I gather that just in
case someone gets cataracts 5 years from now they're going to say "don't".
The official instructions now are that more than 40 inches distance (100
cm?) is safe.
There's some confusion because we are warned about UV rays from the sun.
The difference is that glass filters out most of the harmful rays, or so
it is presently believed. Outdoors there's no glass, and precious little
ozone layer it now seems, between us and the sun. The UV bulb, however, is
covered with glass.
I note also that the AQA bulb from Voltarc is made for aquariums. People
sit and stare into aquariums all day for THERAPY!
Happy hunting,
Judy
And PS to Adam: Congratulations on graduation!