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

>In "Photographing in 3D" from Reel 3D, the author mentions that an
>ancient Greek (can't remember his name) was the first person to notice
>that each eye saw a slightly different image. ( I'm sure he wasn't the
>first person in the world who ever noticed this, but maybe the first to
>write it down. I noticed it as a kid.)
>They also mention that there were some drawings or paintings done before
>the advent of photography which displayed this phenomena. Does anybody
>know what these paintings are?
                                Ray
 I think this was Euclid ,certainly Euclid did write and produce diagrams
on stereo vision and I believe he was an ancient greek. As for the drawings
and paintings and other illustrations of the way stereo vision works or
actual stereoscopic paintings and drawings Leonardo da Vinci did some
illustrations for stereo vision. He also illustrated a stereo camera
obscura with two pinholes although the point he seemed to be trying to make
here is that the light traveled  in all directions from the object. Also he
described a large scale literal camera obscura (Darkened Room) opening onto
a piatza with holes at various points in the wall. If he had used either of
these to actualy make drawings as the camera obscura was sometimes used for
in order to illustrate his point the results would be stereo pairs, hypers
in the case of the piatza. Even though he probably would not have known it
himself and he certainly does not seem to have put two and two together and
invented a stereoscope or even discovered free viewing. In fact, perhaps
for the sake of his argument he seems to have regarded the images as
identical when of course they are not even though he realised our two eyes
do not see identical images so perhaps this was before his realisations
about vision. I have not come across any illustrations made by Da Vinci's
device but they could be stereo although he most probably would not have
known it.
 Brewster in his rivalry with Wheatstone made much of the discovery of a
pair of  drawings by the Florentine artist Cimenti which were supposed to
be a stereo pair. I have seen a reproduction of these  and they are not
very convincing a lot of the effect is actualy pseudoscopic ,it seems to be
accidental. Talking of Wheastone of course he did produce stereo drawings
before photographic images and only later asked Talbot and Daguere to try
stereo photographs.
 Salvador Dali has produced stereo paintings and apparently claimed to be
inspired to do so by discovering that some of the paintings of Dutch artist
Gerard Dou were stereo pairs. One pair is illustrated in the Japanese
version of the stereograms book but they are small and dark so its hard to
judge .P.J.Homer



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