Re: [photo-3d] Tri-Delta Prism stereo attachment

[Peter Davis <pd@xxxxxxxxxxxxx>]

Oops!  I forgot one other point:

Flash
-----
The Tri-Delta Prism should work perfectly well for flash.  However, since 
the camera is basically pointed up at the ceiling, the flash is too.  I'd 
love to find some kind of flash adapter that will let me angle the flash 
forward by 90 degrees.  The only one I've seen is a large expensive bracket 
for about $120.  I'm still working on this one.


At 08:56 PM 12/06/2000, you wrote:

>I've continued to play around with the Tri-Delta Prism stereo
>attachment.  I now believe that this is a very well-designed and
>manufactured item.  It give true stereo images through a regular
>range-finder or SLR camera, and the overall quality is excellent.  There
>are, however, certain quirks:
>
>Viewer
>------
>I think the viewer is the weak link of this system.  It's small, gives very
>low magnification, and has a diffuser which adds a visible "grain" to the
>image.  I'd love to try to build a better viewer for this system, but I
>don't really know where to start.  Has anyone ever tried or heard about
>something like this?
>
>The other problem with the viewer is that because it is so small, you don't
>get the sense of being enveloped by the image as you would with a larger
>viewer.  I think there's too much peripheral vision left open.  If I ever
>build a viewer, I'll try to solve this too.
>
>I've actually tried cutting some of these slides in half and mounting them
>in horizontal half frame mounts (from Paul Talbot, by way of Don Parks ...
>Thanks VERY much, guys!!!).  The results are excellent!  They produce
>really good pairs, when viewed in my Eckeren viewer.  This makes me think
>that a really good, lighted viewer with good lenses would be a great asset
>to this system.
>
>Vignetting
>----------
>In my tests, I get some vignetting at the bottom corners of the image.  I
>suspect this may be at least partly due to the fact that I don't have the
>original adapter rings, so I have to use a pair of step-up/down rings which
>spaces the unit about 3mm further from the lens than it should be.  I'd
>love to find one of the original rings, or at least a machinist who could
>make me something like it.
>
>Grain
>-----
>Because the system splits a regular 35mm frame, the individual film chips
>are smaller (ie, grainier) than larger format stereo images.  They're
>actually not much smaller than Realist chips, but they're near the
>borderline for acceptable (to me) grain for Kodachrome 64.  I'm wondering
>if anyone's every tried to build a stereo attachment like this for a medium
>format camera.
>
>Projection
>----------
>The Tri-Delta system includes a projection adapter which allows you to use
>the taking attachment to project these slides.  Basically, you put the
>Tri-Delta on your project lens somehow, and then put this device on
>top.  It's basically a 45 degree angle mirror and some polarizers.  I've
>never tried this, so I can't say how well it works.  There's some kind of
>plastic ring meant for putting the attachment on a projector lens, but I
>can guess how it's supposed to work.
>
>-pd
>--------
>                                  Peter Davis
>                   Funny stuff at http://www.pfdstudio.com
>                   "The artwork formerly shown as prints."

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