[photo-3d] Stereo window tutorial

[Paul Talbot <ptww@xxxxxxxxx>]

As mentioned in an earlier message, I have developed a
"stereo window tutorial" set of images.  If I picture
is worth a thousand words, you can now have over 5,000
words' worth (times two!) of stereo window explanation
with this 5-slide tutorial.

Each slide has a brief accompanying explanation of what
to look for.  Each of the five images are created from
the same shot; only the cropping/mounting is different.
The set starts with a slide mounted with the window
at/beyond infinity, similar to what happens when twin
2x2 slides from a twin rig or cha-cha (no toe-in) are
mounted without masking to create a correct stereo window.
In sequence, the next four slides show:
  - stereo window with the scene "too far" behind the
    window'
  - "mounting to the window" with the scene starting
    right at the stereo window;
  - through the window effect;
  - window violation.  Note that a window violation is
    NOT the same as "through the window," and the slide
    tutorial set and accompanying text explain what to
    look for to see and understand the difference.

If you are new to stereo, or if you are still learning
about the stereo window, or if you ever need to teach
friends, relatives, or your fellow club members about
the stereo window, this could be just the ticket you
need.  Save yourself 5,000 words! ;-)

Many of us have been down the route of taking images for
several years and using Kodalux mounting or self-mounting
without understanding the stereo window.  I know I've been
down that road!  Now you can see it for yourself and save
the frustration of looking back a few years down the road
and seeing how many of your favorite images are compromised
by an incorrect stereo window.

This set of five images was projected during the DrT/DrDave
mounting workshop at the convention in Mesa.

Paul Talbot