A question for clarification. When you say high pressure mercury bulbs,
do you mean a special bulb that is used in a device similar to what we
call a "plate burner?" If so, the cost of these devices put them out of
reach of many list members and hence the interest in Fl tubes.
I might mention also that a carbon arc will produce a lot of UV and
can be used successfully for alt-process. They are, however, dangerous.
Bob Schramm