Re: Late evening thoughts on stereo formats

[P3D Greg Marshall <greg.marshall@xxxxxxxxxxxxxxx>]

Gregory J. Wageman writes:

>>I think you have described polaroid's vectographs, from around the 40s?

>Dr. T. assumed that as well.

>The original post mentioned transparancy, however, so I read it as a
>stereo transparency pair on a wall-mounted lightbox with the polarizing
>filters directly attached.  Each patron would wear polarizing glasses
>and in essence "free view" the pair.

>I'm not sure how well that would work out, because the required horizontal
>displacement of the images, even with polarization, would require
>some eye divergence (or at least, less than normal convergence).  It
>would be like viewing small polarized projection images where the two
>weren't superimposed, but side-by-side.

>       -Greg

I'm not sure what Dr. T assumed, and I haven't yet had time to check out
what a "vectograph" is, but what I meant is like a lenticular print in
that
left and right are combined into one image.  For example, with digital
processing you could produce an image with alternating pixel columns,
one pixel from the left image, one from the right, etc.  The tricks are
(1)
how to produce a polarizing "mask" with a corresponding alternation in
polarity (I know an expensive way to do this, but hope there is some-
thing better), and (2) how to align the mask to the composite image.

The points made previously about the problems of viewing stereos while
moving and/or from severe angles are well taken, but I still think it
would
be an awesome experience.  Indeed, I think backlit transparencies is a
great way to display most photography.  My involvement in this was to
develop and manufacture large, thin lightboxes that could be hung on a
wall.  I gave up when I found that a company which holds some key
patents in the area was planning to do the same thing.  But I still have
not seen any such products.

-Greg


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