P3D Re: The Stereo Window (was: More Lenticular Queries)

[Gregg Podnar <Gregg_Podnar@xxxxxxxxxxxxxxxxx>]

>      Greg Wageman:
>      Um, OK, but what's your point?

       Perhaps I've been skimming the thread too lightly.  It seems
       unproductive to argue about the edges of the view and the
       stereo "window".  My point is that the frame is indeed a 3D
       artifact in the scene.  I was offering an example which I hoped
       would further demonstrate Abram's explanation.
       
>       George Themelis:
>       >when you overlap the edges of a slide mask on the screen
>       >... It is not stereoscopic.
>
>       Abram Klooswyk:
>       Not stereoscopic ?? The overlapping edges of the mask,
>       or stereo window for short, has the same right of being
>       called stereoscopic as any image point in the 3D scene.

       Producing the windowless stereo view on a sphere seems
       extraordinarily difficult.  But let's go halves: producing
       a stereo view on a cylindrical surface: it has a top and bottom
       edge but no sides.
       
       For proper stereo separation throughout the whole image, we 
       will need a rig which takes a proper stereo exposure for each
       pair of very narrow vertical stripes around the cylinder.
       (Stiching together a few frames taken by a pair of cameras
       rotated a few times will not suffice.)  This rig would not be
       too hard to build depending on the resolution desired.
       There will still be some distortion as the rig must rotate
       about the center of the pair, rather than each lens's optical
       center.
       
       Using this approach with lenses which will cover 180 degrees
       vertically allows projection on a sphere but distorts as one
       views above or below the 'equator' and fails completely at 
       the poles.
       
       Gregg
       
       
        


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