Re: [photo-3d] Are beamsplitters crappy?

["John A. Rupkalvis" <stereoscope@xxxxxxxxxxxxx>]

----- Original Message -----
From: <pd@xxxxxxxxxxxxx>
To: <photo-3d@xxxxxxxxxxx>
Sent: Tuesday, January 09, 2001 8:35 AM
Subject: Re: [photo-3d] Are beamsplitters crappy?


>
> Bryan Mumford writes:
> > sstiles pointed us to the web site http://www.3dquarium.com
> >
> > I looked at this web site and the sample images. I was struck by my
> > dissatisfaction with the images taken with their beamsplitter. It
> > leaves a very narrow image space for the stereo pair. I suppose this
> > is unavoidable, but I had not seen it demonstrated before. Would
> > others agree that beam-split pairs are unsatisfactory? I didn't think
> > about it this way before, but I'm getting four times as much picture
> > data in two full frame cha-chas than I would get in a single frame
> > split image. Maybe a beamsplitter is not a worthwhile project after
> > all.
>
> This has been discussed before.  A splitter does, of course, split the
> frame, so you only get half the area for each half of the pair.  On
> the other hand, you can get moving subjects, sports, etc. in a way you
> can't with the cha-cha method.  Those are only two options:  there are
> also full-fledged stereo cameras available for anywhere from about
> $100 up to $4000 and more.
>
> You could try to build a splitter in the style of the Tri-Delta
> Prism.  This places two images, rotated 90 degrees, on one frame of
> film.  The result is that each image is about 18mm tall and 24mm wide
> on 35mm film.
>
> -pd
>
>
> --
> --------
>                              Peter Davis
>                Funny stuff at http://www.pfdstudio.com
>                  The artwork formerly shown as prints
>     List of resources for children's writers and illustrators at:
>                   http://www.pfdstudio.com/cwrl.html


An image splitter does split the frame.   A beamsplitter does not.   Using
ordinary 35mm still cameras, the frame is about 24mm tall and 36mm wide.
The full frame area is utilized, with no loss (see my other postings).

JR