P3D Re: Twin SLR

["Robert J. Vaughan" <k0mz@xxxxxxxx>]

>    Recently I obtained a second Minolta SRT series camera. It was 
> cheap
> and in fair condition. (I really didn't want it but at $75 it was 
> one
> of those too cheap to pass up deals) So now I have an SRT-101 and 
> its
> slightly improved brother, the SRT-202. Fundamentally the same 
> camera.
>    So the thought of doing twin camera stereo crossed my mind since
> both these cameras are sitting on a shelf doing nothing ever since I
> moved to medium and large format. If anyone can steer me toward some
> reference material on doing twin-camera stereo I would appereciate 
> it. I
> do know there are twin-camera mounting bars out there for large $$, 
> but
> do I really need to get one? Is there an easier way?
> 
> -Fred
> 
> 
   I made two twin-camera bars for mounting a pair of Canon F-1 SLRs. 
One has a base of 170mm and the other is 600mm and both are made from
1/2"X1 1/4"X 1/8" extruded aluminum stock.  The 600mm unit requires an
additional piece of 1/4"X1" material to stiffen it from twisting.  The
F-1 twins are secured with the 1/4"X20 tripod screw and the aluminum L
shape has the short section up and resting against the front of the
camera bodies for stability.  Some of the material needs to be cut out of
the bars to fit around the camera mirror boxes. 
   I trip the shutters on the F-1s with a dual cable release for the
170mm and hand syncronize as best as possible those mounted on the 600mm
bar.  While the 170mm base is somewhat hyper, it is still usable for most
subjects.  I use either a pair of 28mm or 50mm lenses for the 170mm bar
and find that 135mm lenses make great views with the 600mm bar.  600mm is
about as far as I can reach for tripping shutters and 170mm is
comfortably close for the F-1 bodies.  With practice, I can photograph
moving objects with reasonable success.
   I made a special negative carrier which holds both L&R films one above
the other side by side.  The film gates are 7-P wide which enables easily
adjustable stereo windows for each view.  Using an Omega D-II 4X5
enlarger, the images are projected onto a special easel that permits L-R
sequenced printing of each view onto a single piece of paper.  I move the
paper between exposures and locked adjustable edge stops on the easel
positions the paper perfectly for each image (once it is set-up for this
type of printing run).  I have made a number of other neg carriers for
the printing of other stereo formats onto single pieces of paper.  (Each
complete stereo view requires only about 15 seconds more time for
printing than it takes to print single flat views.) 
  Most any well stocked hardware store will have the extruded aluminum
and the larger camera stores generally have junque boxes where you can
find extra tripod screws.  With several hours of measuring, planning,
layout work, and drilling, fine stereo bars can be crafted for most any
twinned cameras.  Let your imagination and creativity guide you in your
design.

Robert J. Vaughan