I'm looking for opinions on these two types of distortion that to my
eyes look somewhat similar. If both cameras are yielding the same
barrel distortion, will this foul up the 3d image? Same goes for
Keystone distortion - although Keystone problems are due to
composition and not to lens properties. Again, if both cameras
reflect the same Keystone distortion, will this foul up the stereo image?
Thanks,
Steve

Steve wrote:

>If both cameras are yielding the same
>barrel distortion, will this foul up the 3d image?

The stereo pair will be comfortable to view but will appear strange.  Keystone distortion is also comfortable to view and it will look perfectly natural if it was introduced by tilting a normal camera.  If you try to correct  for the "distortion"  like you would for a 2D photograph or with a view camera, then the view might look odd.  The opposite is true for a phantogram.  If the keystoning introduced by the camera is not corrected the phantogram will not appear to lie flat.

Oleg Vorobyoff