Melting RBT slides = toasting marshmallows!

[P3D <JGoldenRRP@xxxxxxx>]

On melting slide mounts and film chips....

>>Dr Tee...said:  Is something unique about the RBT mounts?
Do they tend to get not and melt easily when projected with the black side
towards the lamps?

Gee....my guess is if you are melting RBT mounts with your projector....you
probably have kissed that image mounted in it goodbye as well, bowed or
burned irreparibly.  Better get out the marshmallows, Grahm crackers...and
hershey bars...."time for semores....cause you got film chips no more!!"

The RBT mount is designed to be projected with the reflective WHITE side
toward the projection bulbs, using the BLACK side (specifically NOT designed
to face the hot projection bulbs) means you are conducting the bulb
heat...rather than reflecting it.....and having owned a COMPCO with 500 and
750w bottles in it.....I would wonder how long a film chip can stand in a
projector without permanently damaging it.

Dont want to point the problem all to the projector but it sounds like fan
ventialtion needs to be modified, corrected or improved on before you let
slides sit longer in that projector.
Dr T has the specifics on the hot and cool running temps on the COMPCOs,
TDC'd and other older projectors....check in with him for how to cool down
these units.

The RBT 101 Projector uses halogen technology....and with the 250w or 500w
system....the slide is kept very, very cool.....in fact you could leave the
slide in ther all day long...the danger would not be heat...it would be the
bleaching out and fading of the image over time from that intense light. The
RBT mount was designed primarily for this projector.....and the consideration
of older style projectors was not ignored....but using the black side of the
mount, facing a 500 to 750watt bottle for more than a few seconds, nix
glass....in my mind...not a great idea in any mount...and I would get the
slide under some glass.. an RBT,EMDE or an Albion... Even then.....never mind
the mount....but your delicate emulsion....OUCH!

I had an installation of dupes of beautiful 1950's Diner Kodachromes
installed at a museum out here...for about six months...and those images were
backlit in a viewbox...using standard flourescent tubes....covered with UV
filter sheets....and those boxes got pretty hot, nowhere near as hot as an
older projector (pre-Themelisized)...but the white side faced the bulbs, to
reflect heat...the black side was to the viewer....which worked really
nicely.

Think about it....on an unusually hot, humid sunny day....given a car with no
air conditioning, would you rather drive in a white car with a white
interior...or a black car with a black interior. 

On a cold sunny winter day, given a car with no heat , would you rather drive
in a white car with a white interior...or a black car with a black interior.
Having owned both color schemes in my life....I know the answer for myself.

Stay cool...and warm where appropriate....Jon Golden  RBT USA





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