Re: Custom 3D video cameras

[P3D Larry Berlin <lberlin@xxxxxxxxx>]

>-Greg W. comments:
>As we discussed not too long ago in long and painful detail, offsetting
>the lenses from the center of the film apertures is equivalent to masking
>off part of the image.  In conventional stereo still cameras, the lenses
>are offset inward with respect to the center of the film apertures.
>
>So it seems to me you could make a thin metal mask to block a vertical
>strip of the right side of the left CCD (as seen from the rear), and
>the left side of the right CCD and obtain the same results as shifting
>the lenses, except that you will lose a bit of image area.  If the masks
>were attached to adjusting screws, and slid left and right in horizontal
>channels, this would allow setting the window.  Ideally you'd want them
>coupled, of course.
>
>	

If you consider what the CCD is to a video camera, you definitely don't want
to mask off portions of it. You want each part of it to get some portion of
the image. The CCD chips aren't film in a channel so could be moved to
accomodate the window placement. It is the same as masking to move the CCD's
and it makes sure they get full exposure for important parts of the image. I
suggested to Ray that he use a proportional movement of both camera (CCD's)
and the lens. That way you could adjust the stereo base by moving the
cameras apart and the lenses would proportionally move to maintain a
particular window. The window could be independently adjusted too by
movement of the lenses. 

Larry Berlin

Email: lberlin@xxxxxxxxx
http://www.sonic.net/~lberlin/
http://3dzine.simplenet.com/


------------------------------