P3D Re: PHOTO-3D digest 2823

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

I wrote:
>An interesting point is that the term stereoscope was used for opaque
projectors in 1815 several years before Wheatstones use of the word.<

To which Ron Labbe replied

WHAT?
I never heard of this! First, opaque projector in 1815? What was projected?
Second, it was called a stereoscope? What reference do you have for these
purported facts?

My source of information is "The History Of Photography" Helmut and Alison
Gernsheim who mention a J.G.A Chevallier who decribed a magic lantern for
opaque objects in "Le Conservateur de la Vue" published Paris 1815 (Second
Edition).
  Whats more according to them the term stereoscopique is used by Belgian
jesuit Francois d'Aguillon in "Trait d'optique" published Antwerp 1613 !.
This is in the introduction to the stereo section of "The History of
Photography".
  There is no reference to what was being projected in 1815 but at that
time and  earlier ( late 1700's) magic lantern shows known as
"Phantasmagoria" were popular . These were characterised by three main
inovations in projection one of which was the use of opaque puppets and
possibily sometimes live actors which were projected to give moving images
. Another was projection onto smoke although I dont know if this was used
with opaque projection or just with slides which were also used. Projection
of a real object into smoke is interesting from our point of view as would
seem to be capable of giving a 3 dimensional almost holographic image
without any viewing glasses. Perhaps this was why the term stereoscope was
applied. The third inovation was to move the projector back and forth on
wheels which were coupled to the lens in such a way that it was
automaticaly adjusted so as to keep the focus sharp. This gave the same
effect as a zoom lens and was used make the images move towards or away
from the audience. I have various sources for this information mostly from
the UK Magic Lantern Society of which I am a member.      P.J.Homer



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