Well, here is a case of not having enough data. It was some time ago.
A neighbor who worked for Sylvania Electric Products in Wheeling, WV
(now out-of-business) gave me a lot of flourescent fixtures and bulbs.I had
maybe four or five fixtures for 48" bulbs and five or six fixtures for
96" bulbs. I made a bank of the 48" fixtures and laid the print frame right
on the bulbs (these were industrial fixtures of the type known as strip
lights). The exposure was in fact at least a couple of hours maybe longer.
I just watched the paper until it looked good. Now that I think of it
the bulbs did look bluish. They could have been what were called "daylight"
bulbs. Do they still make those?
I still stick by my original advice to Phillipe. Not knowing what is
available in Belgium, A trip to an electrical contractors supply company
should yield some data on the availability of FL bulbs that produce a lot
of ultra violet. Also I know nothing about Phillipe's budget. I still
think FL bulbs are the least expensive way to go.
Did we not have a long discussion about light sources some time back
on this list?
Best wishes,
Bob
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