P3D Re fluorescent lamps

[Peter Homer <P.J.Homer@xxxxxxxxxxxxx>]

As it now seems that the original post was about lamps for viewers rather
than colour photography that would seem to be a lot easier to do .Many
fluorescent lamps other than "Grow Lux" apear to the eye to give a better
white light than tungsten . As for emitting UV I suppose thats possible as
the actual mercury vapour emission inside the lamp is mostly UV with some
green to violet visible but that should be absorbed by the coating inside
the tube which then fluoresces  in various visble wavelengths. Hence the
term fluorescent lamps the glass tube itself should absorb any remaining UV
,if there is any UV left what about the viewers eyes! as well as the slide
at this close range .Although there should be some protection for the eyes
afforded by the lenses as long as they are not quartz.
 But while we are on this subject I seem to remember there is a viewer
which uses fluorescent lamps although it is for medium format 120 rather
than 35mm it was featured a while back in stereo world . If I remember
correctly it actualy had two lamps one to view slides and the other to top
light prints there is a switch to go from one to the other. I rember
wondering if it could be modified to take antique views including tissues
which are designed to be viewed both ways.  Better still replace the switch
with a rheostat in a Wheatstone bridge arrangment so that you could
smoothly dissolve from one to the other but I think that would require
tungsten lights as fluorescents require a minimun voltage to operate at
all.  I belive this viewer has been mentioned on this group quite recently
I will check my back copies of stereo world to see if this information is
correct.      P.J.Homer



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