Re: Liquid optic or cooling element ?

On Nov 19, 8:20 pm, "Adam Norton" <AnortonREMOVET...@xxxxxxxxxxxxx>
wrote:
"Adam Norton" <AnortonREMOVET...@xxxxxxxxxxxxx> wrote in message

news:13k3mfcd53cf7fd@xxxxxxxxxxxxxxxxxxxxx



Pure water also lets pass more UV than practically any IR filter available
even today. This illuminator may have been used in the printing industry
to expose printing plates that were covered with photoresist which is
sensitive to UV or blue light. Look up gravure printing.

I just rembered that the original German description indicates this was a
cinema slide projector, so it was not used in the printing industry.

-Adam Norton

Your words make sense, and yet the mystery thing about it is that the
type description is used in the "normal" cinema slide and roll slide
boxes --- the only difference by these projectors was the projecting
optic, that was between 200 and 1000 mm. lenses ; that could sound
much, but while these was huge size slides these projectors needed
these huge optics, optics that was often also used in the Episkop and
Epidiaskop , -- at not I fittet a tradisional 400 mm. , and there
another reson it must be a projecting unit, becaurse the old type
steel tube they used in these huge format projectors generaly, fit
what I would say "almost" interchangable , -- there are a slight
difference in the distance of the two bilts that hold the bottom tube
in place , yet also a distance piece will be needed, but this is
details , except this unit also has an exchangable front lens , guess
the front lens in these condensers -- like in the Prado 500 6x6 front
condensor lens is different, if the projecting optic are 80 mm. or the
400 mm it maximum was fittet with .
All in all I guess they simply called these animals "Leitz Typ IV-BL",
and then there was a choice of gadgeds and lenses to chose from ;
still not one link about just this issue.And allready little enough,
even from what I understand , they was in many lecture halls and not
just in germany,
Then if we agrea that the Ir. will absolut be filtered out, but the
U.V. --- I think that will pass right thru ,and then what is won
beside what from I heard from fellow collectors ; "They newer cared
about fierce heat , except at the plane where the film was situated ,
not that is only one place and true ; from other diaskops and episkops
same age as you suggest, , there with the 250 watt. lamps both 110 and
220 volt , there often was no fan -- but with the standard 500 watt
both 110 and 220 volt there allway's was , and as this fine old thing
is as new , I found at the lamp holder a stamp saying 500 watt 220
volt . Not that is not much , but the most you can run without cooling
fan , beside I found that other "Leitz Typ IV-BL" do carry a cooling
fan . So I guess this one is simply an early projector Typ IV-BL.

I will give your advise a bit more thought, I think there are more in
your words ; but I wonder if I ever find the full descriotion.

Thank's
.