Two Camera Stereo

[P3D Bob Shotsberger <bshots1@xxxxxxxxxxxx>]

In reply to Neil Harrington, 2 Camera Stereo

This is my "low-tech" way to make 3-D views.

I've been using two Minolta SLR cameras and two projectors for over five or
six years now and find it quite satisfactory.

When I first tried, just to see if I could get it to work, I had two old
Minlota SLR's, a Model 100 and a Model 200 mounted on an aluminum bar, each
camera had a 50m/m lens and i used a pair of projectors, one a Kodak
carousel and and the was a Bell and Howell slide cube projector. Believe it
or not the lash up worked. I now use two Minolta SLR's, Model 370, mounted
on a solid bar with the cameras about 7 inches apart, lens center to center.
I call it "Gorilla" vision system because I have been told that is how far
apart gorilla's eyes are. Reel 3-D's dual cable release is used to synch and
trip the shutters, when they get out of synch it takes about 1/2 an hour to
get them back in synch. Provided I trip the shutters fast enough I can
usually get good synch out to 1/250 almost all of the time and over 50% of
the time at 1/500. I have stopped water spashing and kids throwing a ball.

Don't know how my views look as prints as all I do are slides and project
them using two old refurbished Ektagrahic III projectors. I do use the
narrow (24 x 32 m/m) (Normal is 24 x 36 m/m) Gepe 35 m/m mounts from Reel
3-D to mount and mounting is done using the Reel 3-D mounting guage on a
small light table.

After having gone thru several stages of sloppy or/and "artsy" mounting I
have found for my family and friends to enjoy looking at my 3-D slides in
3-D whether in a viewer or projected I must pay strict attenion to the
mounting of the views. To me to have my family and friends enjoy with me my
views is the whole purpose of taking them.

I have found that the view must be "natural" looking to the person viewing
it or they just don't care. When mounting you must pay attention to the
window and be sure the left eye does see more of the right side of the view
and the right eye sees more of the left side of the wiew, just as you do
when you stand 5,7 or 10 feet from a window and look out of it. Also the
film chips must be mounted perfectly horizontally and vertically (no
rotational error) to each other. After the first "trial" mounting I preview
the slides critically in a viewer looking for all of above points - left -
right window boundries - horizontal - verical alignment, then I check it on
the screen and if anything is not as it should be, I will try to remount it,
if I can not successfully remount it, it is trashed. 

Since I also am a railroad hobbyist, I take lots of train pictures and in
most train pictures there is some gravel around the track. To guage the
accuracy of the horizontal and vertical mounting (rotational error) I make
sure the same pieces of gravel show at the base of the view, in both film
chips. I use similar "tricks" to be sure all views are mounted just as
critically, flower petals near the frame, marks in the concrete, etc. Being
this picky about mounting does not mean that I must always keep my
subject(s) beyond the window, but it does mean when I break the window, it
is broken better. My view of a giraffe sticking his head off of the screen
into our living room is very efffective.

Each frame is then cleaned using a "Staticmaster", the film chips firmly
taped in place and the mount sealed shut and it is rechecked to make sure
nothing moved as it was being sealed up. It takes me over 15 minutes to
mount each view.

When you do not follow those guide lines for mounting views, you quickly
tire your family and friends and they lose interest real quick in seeing
your views! When I first started and "slapped" my views in mounts I would
have people running out when I wanted to show them some "great, neat 3-D
pictures", now that I follow the rules some people who used to run now ask
to see my views -- occassionly.

This is a very quick overview of what I am doing. If I haven't scared you
off, using paired 35 m/m cameras and projectors is a good way to go for 3-D.
Try it you'll like it.


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