Re: terminology

[P3D John W Roberts <roberts@xxxxxxxxxxxxxxxxx>]

>Date: Fri, 14 Feb 1997 20:40:16 -0600
>From: "P3D Dr. George A. Themelis" <fj834@xxxxxxxxxxxxxxxxxxxxx>
>Subject: Re: terminology

>In this case, it's a simple matter of "public relations". I regard my twin
>X-700 assembly to be a *single stereo camera*, which I specifically designed
>and built to take stereo pictures. 

This "designed and built" puzzles me.  What exactly did you do?

- Determined what I wanted (a working stereo camera, made of new components,
    with some of the modern features).
- Researched the properties of various component cameras, selected the X-700
    as providing the best match in features for the price at that time
    (in my opinion).
- Studied the physical and electrical characteristics of the X-700.
- Determined the minimum spacing that would permit full opening of the X-700
    backs while mounted.
- Purchased hexagonal head cap screws, glued on washers so they would go just
    the right distance into the tripod mounts of the cameras.
- Selected a metal bar that would be strong enough for the length needed,
    cut and polished it.
- Drilled holes in the bar so the rewind buttons of the X-700s could be 
    accessed without removing them from the bar.
- Mounted an external switch (needed because of the electrical characteristics
    of the X-700), with the bar as the electrical return for convenience.
- Made electrical release cables out of conventional mechanical release cables,
    devised a wiring scheme that would prevent false triggering of the shutters
    during assembly / powerup / powerdown.
- Put brackets on the metal bar to prevent the X-700s from yawing during use.
- Assembled and tested the assembly, developed an operational protocol for
    the system (which is significantly different from the procedures used
    for a single X-700).

For the longer bars, I also developed an improved switching system, a sturdier
tripod mount, and a method to adjust the pitch, roll, and yaw of each camera
using small screws.

I consider that to be real design and real construction of a real stereo
camera. It performs functions that the X-700 was never intended to do, and
that one X-700 can not do. The fact that it uses X-700s as component parts
is irrelevant. That's why I think the term "dedicated" would be better than
"real" to specify the 1950's devices which are irrevocably committed to
being stereo cameras. For that matter, a "siamesed" camera would be a 
dedicated stereo camera too, since you can't very well disassemble it into
two working 2D cameras. A "twin" camera like mine is not dedicated, since
I can take it apart and use the X-700s individually.

As an analogy, if I want a computer at home, I generally shop for motherboard,
processor, memory, hard/floppy/CD drives, keyboard, case, operating system,
and so on, then take the parts home, put them together, and it works. I build
the computer, even though I didn't build the components that make it up.

>I too define "real stereo cameras" as cameras designed to take stereo
>pairs.  Putting together two SLRs and struggling to make them perform a
>function that they were not designed to perform and fighting against
>everything that can go wrong (specifically: unmatching focal lengths,
>unmatching exposures, unmatching focusing, and, most important, not
>synchronized shutters) is not my idea of a real stereo camera.

I bought two sets of lenses off the shelf that match perfectly as far as
I can tell. I usually use autoexposure because it almost always works OK,
and I seldom have a problem with unmatched focus. As far a synchronization
goes, sometimes a cable slips a little or gets corroded, but when
everything's set up properly and polished, and when the cameras have good
batteries with equal use on them, I can *expect* to get synchronization
on blowing leaves, flags on a windy day, birds flying, and rushing water.
(And I can check by listening for the two shutter clicks, so I can usually
get another picture if there was a problem.) 

I believe you mentioned that you got the "store boughten" electrical
release cables from Minolta. Do you actually have shutter sync problems
using them?

Maybe for some people this is like that "Real Men" / "Real Women" fad
that came and went some years back. (Example that comes to mind: How many
Real Men does it take to change a light bulb? Answer: none - Real Men aren't
afraid of the dark.)

So should we put together a "Real Stereo Cameras" list?

 - Real Stereo Cameras don't have a batch of wires hanging around the outside.
 - Real Stereo Cameras don't contain any parts from Home Depot.
 - Real Stereo Cameras can be used as weapons without damage to the camera.
 - Real Stereo Cameras leave a horizontal line on your forehead.
 - Real Stereo Cameras don't eat batteries.
 - Real Stereo Cameras don't pump APS.
 - Real Stereo Cameras were all built before the invention of mood rings.
 - Real Stereo Cameras take their time and enjoy life - 1/200 second shutter
     speed is plenty fast.
 - Real Stereo Cameras don't have pentaprisms.
 - Real Stereo Cameras build up strong calluses on your fingertips (from
     the rewind knob) so you can play the guitar.
 - Real Stereo Cameras would look good sitting on the dashboard 
     of the Batmobile...

:-)   :-)   :-)   :-)   :-)

John R


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