Re: Curved or "warped" mount stereo cards

[P3D Dr. George A. Themelis <fj834@xxxxxxxxxxxxxxxxxxxxx>]

>> I know a lot of stereographers who make stereo cards, but the only 
>> one I am aware of today that is producing a curved mount card 
>> is Thomas A Gillam , of Perkasie PA.  He says 
>> "They look cool" and I can't argue with that.

I have one of Tom's stereo cards of the moon... Just checked it out
and it is slightly curved (or maybe deformed by sitting under a 
bunch of curved views? :-))  Tom is (was?) in P3d.

Regarding Dennis' speculation that these old curved views might
be curved to optimize optical performance (by canceling out
optical aberrations in the viewer), this theory has been discussed
but it is unlikely that it is the case.  Seems that it should be
curved the other way (horizontally) for that to make some sense.

-- George Themelis


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