P3D infinity at zero convergance

[John Toeppen <toeppen@xxxxxxxx>]

"The interoccular adjustments on viewers, not for interpupillary
matching
purposes at all, are equivalent to the horizontal adjustment on a
projector - they move this "infinity center" off your center of
vision.."

I think that you're both right - kind of.....

If the chip were at the focal length of the lens your eyes would focus
at infinity to view the image.  If you look out your window at some
distant hill or tree and adjust your viewer to match this focus you
could achieve this condition.  You would likely find that this is not
the focus that you usually use.  Interoccular viewer adjustments correct
for interpupillary differences and vergance.

Infinity focus places the "window" of the slide at what
distance?...(hint: infinity). I find this whole "window" thread
amusing.  While I appreciate
the need for optimal mounting for projection, different viewing
systems have different requirements. Where is the window on your real
eyes? -
my optometrist shows me a map where my nose clips my field of view.
Aligning the frames around each image is not required to simulate human
vision - just projection.

I usually break most of the "window" rules when I compile jps and
anaglyph images.  The subject of primary interest is often placed in the
screen plane because ghosting is minimized. Others will often place the
nearest object in the image in the image plane.  If one does that the
waterfalls ghosts against the rock, the highlights appear double, and
the image does not evoke the sense of being there.  If not for that then
why bother?

Sure, it is best to only have the flower, mushrooms, or wing tip extend
from the screen with no clipping at the edges - it is a great effect. 
But the fact is that most of the real world just doesn't look like that.
A near branch that is only seen in one eye may be too close - and in the
woods you may brush it aside in order to improve your view. Ignoring it
is actually a part of being there - so it sometimes should be included
in the photo.

Get real. Shoot it as it is.  Be willing to be impressionistic. Realize
that you view your slides a roll or two at a time.  The thread of
continuity created by a series of pairs allows one to paint an image of
a place and time by viewing a collection of images - not just one shot. 
The world is not a salon. Competition is great fun I am sure, but most
of us shoot to recreate a sense of being there.

John Toeppen
http://members.home.net/toeppen/