P3D Re: Realist system flawed?

[boris@xxxxxxxxxxxx (Boris Starosta)]

Dr. T,

I respect your enthusiasm, but I will continue to differ.  I am very
competitive, and I do like a challenge.  Maybe I'm trying to bring you
around to my point of view...

You wrote:

>It started as a joke but now it got serious... I will like to spend some
>time replying to Boris' comments on the Realist system because I consider
>the issue very important, especially for those who are about to make
>choices for their own stereo photography.

Exactly why I made my comments, as well.  I hope Xochi is listening.
Joking is okay, but it can be confusing to those who don't understand the
joke.  That's why clarifying things helps once in a while.

>
>Boris says that that the Realist system is significantly flawed because it
>is non-ortho stereoscopic.  What Boris means is that the focal length
>of the lenses in the Realist camera (which is 35 mm) does not match the
>focal length of the Realist viewers (which is 44 mm)

Thanks for elaborating what I was too lazy to write.

>How important is that mismatch?  Is it noticeable?  What effect does it
>have?
>
>Boris says: "This results in a relatively narrow angle apparent
>field of view, and a "stretched" spatial field."
>If you compare the views of a viewer with 35 mm (ortho) and the standard
>Realist red button 44 mm, you will see a difference but I think this
>difference is not very noticeable or very important.  There is also a
>difference if you use the 44 mm viewer vs. other, cheaper, viewers that
>have 50 mm focal length.

And it is these cheaper viewers (such as the $3 Radix) that you will be
buying, when you want to distribute significant quantities of your
material.  Either to friends or commercially.  I think such distribution is
very important to the long-term success of the _system_.  If you want to
stick with it, you will probably want to share your pictures with others.

I have been distributing my slides to various friends, family, etc. along
with viewers (by now, probably close to 15 viewers sent out to people, to
whom I want to communicate my enthusiasm and give the enjoyment of the
stereo view).  $100+ Red button viewers, nice as they are, cannot serve
this purpose.  In the Realist _system_, the cheap Radix viewer worsens the
mismatch of f.l., leading to stereo viewing that I find unacceptable.  I'll
allow that my standards may not be the same as others'.

>For most people and most subject maters, the effect ("flaw") is not
>disturbing.  The proof is the success of the Realist system in the 50s.  If
>the system was "seriously flawed", it would have not generated the response
>it did.

The proof is also in the apparent failure of the Realist system by the end
of the sixties.  Of course, the "f.l. flaw" in the system may have had only
a small part to play in the demise of popular stereography.  How small was
that part?  Who knows?  I'm just trying to present my viewpoint, given to
you as from a relative NOVICE.

When viewing a stereo slide, my impressions at this point might still be
similar to those felt by a non-stereo-fanatic, such as an average member of
the general public.  Now that I've been looking at stereo slides of
different sorts for over six months, I find that I am becoming accustomed,
or de-sensitized, to these distortions in some slides.  Soon, I will have
forgotten what a member of the general public might feel, looking at a
stereo slide for the first time.  Take advantage of my current impressions
and feedback.

>Ordinary, 2D photography, is also non orthoscopic.  We view our 4" prints
>from a distance longer than the ortho position.  To make things worse, 35
>mm lenses are consider the standard FL in many cameras.  When we go to the
>movies, most people sit well behind the ortho seat.  Same for watching TV.

In 2D representations, spatial perception is an illusion created by
non-stereoscopic depth cues, and distortions are automatically processed
away by the mind.  In stereo viewing, perception of space is "real".  As
such, distortions in the spatial relationships matter a great deal more,
and are not as easily ignored by the mind.  Furthermore, stereo is a medium
which invites close inspection; distortions of any kind are more important
in this medium.

>To stick with stereo, in stereo projection most people sit well behind the
>ortho seats.  Some of the most popular seats are at the equivalent of 100
>mm FL viewing.  If the 44 mm is disturbing, what can be said for the 100
>mm?  I personally enjoy my projectionist spot at the 125 mm FL of my TDC.
>The judges that selected Boris' pictures for awards I bet were also sitting
>well behind the ortho seats.

This underscores my point above, that "experienced" stereo observers have
become desensitized to distortions that might bother the average person in
the general public.  I also happen to think that projecting stereo slides
is probably the worst way to introduce people to the medium of stereo
photography.  Unfortunately, that is how most people are first exposed to
it.

>The orthoscopism that Boris advocates is based on the use of SLR cameras
>with 50 mm lenses and a viewer with 50 mm fl. lenses.  Buy any attempt to
>pair SLR cameras, results in interocular separation that is wider than the
>average 2.5".  For side-to-side SLRs this is 4" which is definitely not
>orthoscopic.

This is simply incorrect.  SLRs can be mounted base to base to produce the
proper interocular separation.  Mine are on a fairly thick baseplate, yet
still produce an i/o of 2.75 inches, which is hardly a hyper separation.
Mounted side by side on a rail, a pair of smallish SLRs can be mounted
staggered side by side (where one is slightly behind the other, to help
bring the lenses closer together) with an i/o of about 3".  My rather bulky
Pentax bodies would produce an i/o of 3.5" mounted this way.  Small point
and shoot cameras would easily produce the correct i/o separation this way.
The difference in image size between the two cameras mounted this way
would be minimal.

>The other day I mentioned the work of this very successful photographer,
>using 28 mm lenses separated at about 5".  Boris is also doing table top
>photography which requires much smaller lens' separation.  He also creates
>computer-generated images.  Others take hyperstereos.   All these interesting
>forms of stereo photography are not orthoscopic.  Why is the matching of
>focal lengths so important for Boris, while the matching of stereo bases
>or the content, is not?

Matching of stereo bases is of paramount importance to me.  I don't know
where I might have given you a different impression.  I'll admit to taking
some liberties with my computer.

>>(As well as close-up views.  It doesn't help that the for
>>use of a standard Realist, the recommendation appears to be to keep the
>>subject more than five or six feet away.)
>
>The recommendation (to keep the closest objects at or beyond 7 feet)
>applies when the scene includes infinity.

(Understood.  I didn't realize the Realist instructions were that explicit.
I thought they simply discouraged close-ups.  My mistake.  Not relevant to
my "f.l. flaw" gripe anyway.)

>you did.  You are not an average person, picking up stereo as a hobby, like
>most of us are.  You started as a photographer and you had the money and
>equipment to proceed the way you did.
>

This is also incorrect, although your mistaken assumptions may be forgiven.
Perhaps it is true that I am not average.  I am an artist, and I do
question what I see.  I do not simply turn away unimpressed.  It is not
true that I started as a photographer.  I became a photographer this past
summer, precisely _because_ of my discovery of stereo photography on the
internet.  Had I not discovered you, Dr. T., I would not be taking pictures
today.

>>Decent quality slide viewers
>>for2x2x2 format are very affordable, and give a higher quality view
>>than even the most costly standard Realist format viewers.
>
>Excuse me?!  You mean the single-element plastic pin sharp viewer that you
>are using is of higher quality than the Realist red button or Kodaslide II
>viewers????

Yes, precisely.  The Realist red button or Kodaslide may have better
optics.  But my entire argument rests upon the relative importance to
stereo slide viewing of these additional qualities: apparent field of view,
orthoscopism, cost.  Adding up all of these advantages of viewing 2x2
stereo pairs in a "Pinsharp," the Realist format viewers don't even come
close.  I invite a newcomer (Xochi?) to take in some stereo views using
both types of formats, and give us their impressions.

Remember, the full 35mm frames produced by my twin rig are some 50% larger
than those coming out of a "standard" (5p? ANSI?) Realist.  Add the
relative "enlarging" effect of the proper focal length in the inexpensive
"Pinsharp", and with 2x2 slide pairs you have a stereo view that is
practically double the size of a Realist slide viewed through the
inexpensive Radix viewer.

>>This doesn't mean that I will never use a Realist.  If I get the money
>>together, I may buy a Realist sometime.
>
>Yeah, right!!!  Sell one of your Nikon FILTERS and buy a Realist camera!
>:-) :-) :-)

I dont have any Nikon filters... YET!  But I will buy a Realist some day.
Really!  If you are nice to me, maybe I'll buy it from you (and then you'll
have your chance to really play some jokes on me!)  And I'll really enjoy
that camera with my custom made viewer.  George, I've nothing against the
camera itself.  I have been criticising the system.

>
>Conclusion:  Yes, the Realist type viewers are longer in FL than the
>Realist camera lenses.  No, for most people and most subjects this
>mismatch is not disturbing, to the point of calling it a "serious flaw".
>For most people (but certainly not all), the Realist system is a better
>way (read: cheaper, more convenient) to get started in good quality stereo.

More convenient?  For snapshooting this is probably true.  But I think
stereo is somewhat wasted on snapshooting.

Cheaper.  Maybe.

To answer this more fully, just let me tell you my own experience when I
came into stereo photography some eight months ago:  To do some learning I
bought two throwaway Fuji "filmpacks with lenses."  Cost: $15.  I was
pleased with the print pair results, easily viewed with a $1 plastic
lorgnette viewer.  For snapshooting, I would say this is a good way to
start.

But I wanted to do high quality slides.  I admit that as an illustrator, I
approached my entry into this medium with artistic aspirations.  As I was
already the owner of an (infrequently used) SLR, I realized that all I
needed was another one to do stereo.  At this time I knew nothing about
viewer focal lengths, "squash", "stretch", or any of the technical stuff.
(Heck, I figured out that "squash" and "cardboarding" were two different
effects just a few weeks ago!  I'm still on the steep part of the learning
curve today.)

I was aware of the Realist, and avoided it simply because it was unfamiliar
to me (it's a thirty year old camera without a light meter), and I had a
hunch: if I shot full frame slides with two SLRs, I would not have to
bother with "mounting".  (Now I realize "mounting" is no big deal, although
it does add some time and expense.  But with my setup, I still don't have
to bother with mounting, unless I want to submit to competitions).  At that
time, getting the Realist would have cost about the same as getting the
second SLR.  So I decided on the second SLR.  If nothing else, I knew it
would be easier to sell, once my infatuation with stereo ended (I think you
know now, as I do, that it will never end).

But now, with what I've learned, I am so glad that I started with that
"hacked" twin rig.  I'm still shooting with it today.  I'm just telling you
my feelings - I might not be here to disagree with you today, if I had
started with a Realist (of course you'll say that's because then I'd have
become a great fan of Realists!).

Is this post too long to make it through Weir's filter?  Larry?

Respectfully submitted,



Boris Starosta

usa 804 979 3930

boris@xxxxxxxxxxxx
http://www.starosta.com
http://www.starosta.com/3dshowcase

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