[photo-3d] Tri-Delta Prism Stereo comments/questions

[Peter Davis <pd@xxxxxxxxxxxxx>]

As many of you know, I'm trying to assemble a working Tri-Delta Prism 
Stereo outfit.  I now have the camera unit, the viewer, the projector unit, 
and the manuals.  However, I'm still missing a ring I can use to fit the 
unit on my SLR, so I still can't actually shoot any pictures with 
this.  I'm also missing the special punch for making the alignment notch in 
the slide mount.  (If anyone knows of a source for either of these items, 
PLEASE let me know.  Thanks.)

I have the following comments/questions:

1) Does anyone have any sample Tri-Delta slides of people?  I'm willing to 
buy, rent or borrow slides.  Before I invest too much time or money in 
this, I'd like to at least see how well it works.  Currently, I have only 
one sample slide, and that's a tree branch against an background of 
foliage.  It looks good, but it's not very useful for judging the 
capabilities of this system.

2) In one of the Journal articles, Eddie Butts recommended using the unit 
upside-down, so it faces the top of the camera rather than the 
bottom.  This puts the two images bottom to bottom on film, rather than top 
to top.  The benefits of this, according to Butts, were that more often, 
the subject would be closer to the center of the frame, where the lens 
optics and center-weighted metering would work best.  Another advantage is 
that you can bend down to look through the camera's finder, rather than 
having to lean back.  However, the viewer would have to be held 
upside-down, with the nose notch on top, and the light-gathering diffuser 
on the top.  This could have been solved simply by designing a lighted 
viewer, but Tri-Delta didn't do that.  Has anyone else experimented with 
this upside-down approach?

The down-side of this method is that vertical lines tend to diverge going 
up, rather than converge.  However, this effect is minimal, according to 
Butts, and may be partly compensated for by shooting from a low angle 
looking up.

3) The mirrors in my unit have some spots.  Is there a way to clean 
front-surface mirrors?  If not, is a good camera repair place likely to be 
able to replace these?

I'm sure I'll think of more later.

Thanks,

-pd

--------
                                 Peter Davis
                  Funny stuff at http://www.pfdstudio.com
                  "The artwork formerly shown as prints."
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