Re: [photo-3d] Re: quiz no. 4

["John A. Rupkalvis" <stereoscope@xxxxxxxxxxxxx>]

----- Original Message -----
From: "Robert J. Vaughan" <k0mz@xxxxxxxx>
To: <photo-3d@xxxxxxxxxxxxxxx>
Sent: Monday, March 05, 2001 3:27 PM
Subject: [photo-3d] Re: quiz no. 4



> Answer by RJV: No and Yes.
> The flash must remain fixed while the camera is shifted because you want
> the shadows to normally be cast onto the background.  If the flash is
> moved the shadows will appear as ghosts in front of the background.  Yes
> if you want that effect as we saw several years ago in SW in one of the
> contests.     These are fun; thanks George.
> Robert J. Vaughan

Yes, they are fun.  Which brings up another viewpoint.  Much of the
commentary in these posts regard correct procedures for achieving the most
realistic, easy to view results, which is a very laudable goal.  Many of the
readers are new to stereoscopy, and need this type of information.

However, I believe that there is also room for information on techniques
that are not "recommended practices".  Those things that will produce fun
effects rather than "perfect" images.  As long as it is clearly stated that
something does not follow the best procedure, but is done for an abstract or
unusual effect, I think such things should be done, or at least experimented
with, as well.

With that said, I would like to suggest the following.  There is a technique
in conventional monoscopic photography for producing "shadowless" flash
photographs.  The procedure is to place a 45 degree true beamsplitter (why
do I have to say "true"?) in front of the camera lens and bounce the flash
off of it.  The result is as if the flash source were emanating from the
center of the camera lens.  All shadows are behind the subject, and
therefore do not show on the image.  This is done for highly detailed
subject matter, such as pictures of wiring or circuit boards or machinery,
and is often applied to macro work, such as the image of the gear train in
an analog watch.

To be used in stereo, the flash (contrary to recommended practice) would
have to travel with the camera.  Also, make certain that the flash reflects
off of the side of the beamsplitter that reflects toward the subject (the
other side would just wipe out the image, totally).  You would also want to
shield the side of the beamsplitter opposite the flash with black flock or
photographer's velvet to prevent flare bouncing back into the lens.

I have never tried this effect in stereo myself, but I would imagine an
extreme "cardboarding" layered effect, sort of like images in a "pop-up"
book.  With appropriate subject matter, it might be quite interesting.
And, certainly "fun".

If anyone tries this, let me know.  I would be curious as to the results.

JR


 

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