P3D Re: Filtered fluorescent lamps

["Greg Wageman" <gjw@xxxxxxxxxx>]

From: Duncan Waldron <J.Waldron@xxxxxxxxx>


>Heat will also destabilize the image. As I recall, a temperature
increase
>of 18 degrees C will double the rate of a chemical reaction. This must
be
>a significant factor in image fade. By "standard tungsten", do you mean
>non quartz-halogen? Quartz lamps do pour out a lot of UV.


I don't know what the exact mechanism of dye fading is.  I suppose it
could be an oxidation reaction, or some other chemical breakdown if the
dye molecules aren't completely stable.  Heat certainly could accelerate
this significantly.  (Probably why they say "Store in a cool, dry
place".)

Yes, I meant non-halogen illumination.  Ordinary tungsten illumination
will fade slides in projection, so you may be right that heat is the
culprit.

     -Greg W. (gjw@xxxxxxxxxx)





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