P3D Re: formats & focal lengths

["John Goodman" <jgood@xxxxxxxx>]

Dr. T. wrote

> Hence the terms
> "stretch" (for wide angle perspective) and "squash" (for long lens
> perspective).  As we know, it is not the taking lens that creates 
> these deformations but the mismatch of taking/viewing angles of view.

As a newbie, I'm curious how the above stretch and 
squash relate to hyper- and hypostereo. A hyper of a 
landscape seems to "stretch" the spatial relationship of 
objects, making the differences in distances between 
objects and the camera seem larger. (Forget the perceived 
change in object or viewing person size for a moment.) 
How imperfectly would narrowing the stereo base from the 
normal ~65mm compensate for the stretch due to using 
~50mm focal length lenses to view a stereo shot with 
28mm lenses? If there are differences in the qualities of 
stretch or squash (stereo base induced versus 
taking/viewing angle of view mismatch), how would they be 
described, and what is their cause?

JG