P3D RBT S1

["Dr. George A. Themelis" <DrT-3d@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

>From the RBT info posted earlier, one camera sticks out for its
uniqueness.  This is the RBT S1 camera, made by joining two 
Konica Hexar cameras.  This is the only rangefinder camera RBT
currently makes.

What does rangefinder mean?  In an SLR camera you are viewing
via the lens that takes the pictures, through a mirror.
A spit second before the exposure, this mirror lifts up to
clear the way and the shutter opens.  The mirror falls down
after the shutter closes.  In a rangefinder camera the viewing
system is independent from the taking lens.  This results in
a more compact and quiet operation (no mirrors to slap around.)  
The Realist-format stereo cameras from the '50s are of the 
rangefinder type.

SLR cameras had become very popular in the '70s through '90s
and, despite the rise of popularity of compact P&S cameras, SLRs 
are still the standard choice of professionals and serious
amateurs.  The greatest advantage of an SLR camera is that
you see exactly what the film will see.  So you know exactly
where you are focusing and what is included in your frame,
you can see the effects of filters or attachments, you can
zoom and see the effect of changing focal lengths, etc.

The RBT S1 is unique as being the only RBT rangefinder camera
and for a number of other features like:

- Autofocus (only autofocus stereo camera ever made - I think)
  Now some will question the value of autofocusing in a stereo
  camera.  The camera will focus manually (via somehow hard to
  control small buttons but these have the advantage that they
  cannot be knocked off like the dial in a Realist or the rings
  in SLR cameras) but the autofocusing is useful in many situations 
  of quick shooting, when using wide apertures for accurate focusing, 
  close ups, etc.  While in Greece and Paris I took plenty of 
  pictures with the focus manually set at 5 meters (about 15
  feet).  In certain cases (when shooting through airplane 
  windows or when the main subject is far away) I put the focus
  at infinity (one button operation).  But I did use a fair
  amount of autofocusing too.

- Lens spacing of 59 mm (this is shorter than the standard
  65-70mm found in most all '50s stereo cameras)  This is either
  a drawback or a plus, depending on your point of view.
  It makes close-ups and people photography look more natural IMO.

- Unique format of full-frame pairs separated by a 4 sprocket
  gap.  As a result it gives 15 pairs instead of the 18 one would
  expect.  You lose some film but you can separate all pairs when
  cutting a roll (no interlocking)

- Compactness.  The camera is about as long and as heavy as a 
  Realist.  If you think that the Realist is heavy then try
  lifting an SLR RBT camera!  So, even though the RBT S1 is a 
  heavy camera but still the lightest of all RBT cameras.  And 
  I can still stick it in my coat pocket.  While in Green Bay
  the only RBT cameras I saw in action were RBT S1s (John Roll's
  and mine).  I did not see a single X3 or X4 (no one was using
  them inside the convention).  I suspect that this has something
  to do with how compact or easy to use the camera is.  My pictures
  turned out great, BTW.

The lenses in this camera are fixed 35mm/f2.0.  The apertures are
linked internally (no awkward external links).  I have been very
pleasantly surprised by the sharpness of these lenses even at wide
apertures.  Also, I LOVE the way the camera handles in the field.
It is so easy to just turn it ON and shoot right away!  (Don't
forget to take off the lens covers!  That's not an SLR, remember?)

The camera favors handheld/available light stereo photography.  
It has a very clever program automation that will select
both aperture and shutter speed so that you are able to take
the picture.  The automatic exposures are dead-on.  Manual exposures
are also possible.  The little flash that comes with the camera
works surprising well for short distances... Pictures look very
natural as if no flash was used.

Now, for some limitations:  The rangefinder nature of the camera
makes it difficult to use filters or other attachments (you do
not see the effect and the metering system is not through the
lens to compensate for them).  You are stuck with one focal
length.  Portraits and other special applications of longer
or wider lenses are not possible.  There have been some problems
with film rewind... I wish my camera had a manual rewind.  While
I understand the advantages of auto film advance, I don't see
any value in automatic rewind.  The S1 motor appears to struggle
in rewind and sometimes (rarely) gives up which temporarily 
leaves me with no camera to use.  (Others don't report problems 
in this area).

I have no regrets about buying or no hesitation in carrying it
with me all the times.  I treasure the pictures it takes and, as 
I've said, my success ratio (pictures kept vs. shot) is over 95%, 
something that is unheard of for me and will not happen with any 
other camera I am sure.

Because the RBT S1 is a very expensive camera, and attracts a
rather special user, I recommend doing some reading about the
Konica Hexar and the S1 and asking for independent opinions.
There is a mailing list for S1 users (RBTS1@xxxxxxxxxxx).
I can add you if you like but it is more useful for people who
already own the camera.

There is also the list for users of modern stereo equipment
(New.3D.Film.Gear@xxxxxxxxxxxxx) which is read by many owners
of different RBT cameras.  This appears to be a better place to
discuss DETAILS about MODERN cameras (no Realists allowed :-)), 
viewers, projectors.  If you do not have a VERY strong interest 
in this area then the photo-3d list should cover you well.

George Themelis

Disclaimer:  Opinions expressed in these postings are all mine,
and not shared with RBT or 3-D Concepts.  I might also have some
of the facts wrong.  Try and get all the facts straight and as 
many opinions from users as you can before deciding on how to 
invest your hard-earned money.