T3D Re: Cardboarding

["William J. Carter, Ph.D." <wc@xxxxxxxxxxxx>]

At 07:15 AM 10/7/98 -0600, Dave, "Dylan The Hippy Wabbit", Spacey wrote:
>Hi All,
Hi Dave,

>Psychologists have known for over two decades that the brain calculates
>stereo on a far finer-grained basis than edge detection.  
I'm only trying to address the specific cues we get from a "stereo" camera.

>Of course if you don't allow any other cues to be available then that is
>what will be used.  Am I missing something?
No, I think you're right. But, in a "perfect world", a sphere would appear
to be "commin' at ya'" half as far as it's width. Does "stereo" fail? If so,
why? What could be labeled as "human imperfection"? And what, if anything,
can be done to improve our impression of stereo information? 

I know, perceptually, "single lens stereo" is quite different from "dual
lens stereo".. Where to go with that, I don't know yet.

>I'm not experienced with these split lens systems, but I'm not convinced
>by the explanation on your web site. 
Since I put that information up, a lot of work has been done. One thing was
to take about 350 single, and dual lens pairs of straws, at varying
distances, to determine the stereo resolution of a SL3D device. It was, as
anticipated, several times greater than the "centroids determing an
interaxial" argument that I first proposed. There is definitely some other
dynamic going on here.

>What would need to be answered first is whether you would get cardboarding
>viewing such a scene with the unaided eyes.  If you put it in a box to
>disallow movement parallax I think so.

>I think you are neglecting the viewing aspect of this.  We see
>stereoscopically through paired lenses, and the only "center information"
>is interpolated by the brain.  Whatever means you use to take the
>photograph that is fixed.
An interesting aspect of SL3D is that It's very easy on the brain. By that,
I mean that it's actually relaxing to look at or watch SL3D. There's a
psychologist I know of who could not see stereo, but saw stereo for the very
first time when he looked at some SL3D video. It blew him away!  Personally,
I find SL3D easier to watch than "real life" stereo, and it's certainly
easier to watch than "flatties".

>BTW, what subject is the Ph.D in?  To put it another way, if I've been
>trying to teach psychology to a psychologist I'd better apologise now.
>;-)
My degree isn't related to this field, my business is. What happened was
that about 10 years ago I grabbed a 3D bear by the tail, and I haven't been
able to let go!


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