Re: Converging fields of view

[P3D Larry Berlin <lberlin@xxxxxxxxx>]

>Neil Harrington  <nharrington@xxxxxxxxxxxxx Writes:
>......  In a Realist-format camera the separation
>of the film gates (center to center) is about 1 mm greater than lens
>separation, which is what provides convergence in the fields of view.

Thanks Neil for confirming the stereo camera geometry. It makes sense that
such a feature would be designed into a stereo camera.

I took the discussion as "pure", or as dealing with basic stereo optical
geometry, which is the same for any camera. The special arrangement that
provides for the "converging" fields of view in a stereo camera still
conforms to the basic geometry, whether the person using the camera knows it
or not (I'm sure many haven't known). I appreciate being able to learn about
the comparisons of the different systems, all of which produce stereo images.

I also appreciate the fact that with a two camera system you can image
stereo of distant objects with a wider base than a fixed camera provides.
This factor makes the two camera system as somewhat preferrable over a fixed
base system, unless most of your photo subjects are at relatively close
range. Even in the normal range it's fun to play with exagerated 3D which is
difficult to do if the lenses are at a fixed separation. It's necessary to
understand the factors involved for either camera system using terminology
that can apply to both circumstances. I guess the ideal would be to have
both a stereo camera and a pair of regular cameras. Or better yet, with
digital one could have a multiple lens (any number of lenses), continuously
variable-base stereo camera with very little actual bulk, no chemical film
processing, no waiting. Has one been built yet? :-)


Thanks,


Larry Berlin

Email: lberlin@xxxxxxxxx
http://www.sonic.net/~lberlin/


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