P3D replies on orthostereo

[Peter Abrahams <telscope@xxxxxxxxxx>]

John (who isn't really nasty, at least you didn't call me The Anti-Christ
like you did Leroy B. re PePax) notes:
>telescopes, binoculars, and
>microscopes are by definition non-ortho because all change
>the perspective to achieve their effects.  Hmmm..  Peter
>wouldn't have a hidden agenda, would he????
>Continuing on, I would agree that ortho is only purely ortho 
>relative to a given individual but I can't see how film 
>contrast has anything to do with ortho which is a rule for 
>correct geometry.
>The world _is_ ortho, it's some of our efforts which aren't.

My agenda here was to stir up the pot, but I've learned my lesson & won't
do it again.  Tele- and micro- photography is not generally concerned with
ortho qualities, though I'm sure there are examples I'm not thinking of.
It certainly is interesting to think of reconstructing space in an image on
those scales.  (Or is a macro that accurately scales all 3 dimensions an
ortho shot?)
(Low) contrast was mentioned as something that can make a photo seem flat,
and I might be inclined to introduce hyperstereo into such a composition to
enhance depth.
And, just to really pick nits, I'd say that ortho-anything refers to a
reconstruction, an image or model or such; not to reality or the actual
subject of the composition; so saying the world is ortho either misses the
boat or is beyond me.  However, some of the most boring books in the
library are about epistemology, phenomenology, and other aspects of this
topic, so I'm not going to stir up that pot (I didn't yet, did I?)

>>(ortho is) violated for good reasons, to enhance imaging, not as a
>>special effect.
George replies:
>That's questionable.  I use it mainly as a special effect...... my personal
>photography is for enjoyment not science.  I enjoy the hyper effect.  It is
>different and it is fun when done in moderation.  But I wouldn't say that
>it "enhances imaging"...

To me, a little hyper (there's that troublemaking term again) draws the
viewer into the scene & enhances it.  This is a subjective feeling that
certainly doesn't apply to portraits.  (It is pretty amazing that if a
stereo portrait causes you to seem too close to the subject, it gives you
the same sort of feelings as 'having your space violated' by someone who
stands right next to you to talk.)

>- Are you using slide or print film?
Both, mostly slides.  I'd like to know how these issues become different
with print media.  Is this related to another question I have, why don't
4x6 enlargements work with Holmes cards, that are usually used with 3x5 shots?
>- What are your favorite subjects (style)?
I mostly shoot telescopes, which range widely in size from a cubic foot to
huge.  These are placed in sunset scenes, but some are inside
observatories.  I'm not dogmatic about optical instruments, when I see a
tree as lovely as a telescope, I'll certainly shoot it.
>- How close do you place your near objects?
Often, I don't have a choice in my composition, but generally anything
within twelve feet or so (very roughly) should be the only object in the
picture, and 7 or 9 feet might be the closest, depends if I'm masking my
mounts.   With my twin rig, close objects can be a real problem.  When
composing with a twin rig, I often check the two viewfinders to see if some
object is going to cause problems.  
>- Do you project your slides?
My 'guinea pigs', whoops 'friends', in the Cascade Stereo Club, are
sometimes subject to my photography.  Certainly many shots that work in a
viewer have too much disparity in projection.  Any shot is better in a hand
viewer, though.
>- How long have you been shooting 3d?
A little over a year.
>- How long have you been using this camera system?
8 months or so.
>- Have you used or are you using anything else?
A Realist.
>- What is your eye distance?
Narrow, 57 mm.
(What is your favorite Xmas present?)
Food.
_______________________________________
Peter Abrahams   telscope@xxxxxxxxxx
the history of the telescope, the microscope,
    and the prism binocular


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