Re: Realist History and the Hat

[P3D Paul Talbot <ptww@xxxxxxxxx>]

Re: Bill and George debate whether Ilex Paragon 3.5 lenses used
on the earliest Realists cause vignetting.  I'm relying on my
suspect memory ;) here, but I believe Charles Piper, in "The
Technical Page," states that vignetting at small apertures is
primarily a function of the design of the camera, not the lenses.
Being pretty green re: technical aspects of camera design and
construction, the exact explanation did not stick with me, but
apparently vignetting occurs when some part (the diaphragm?)
is placed behind the lens.  I recall a chart listing many stereo
cameras and a "behind" or "between" notation for each.  The Stereo
Realist 3.5, like most stereo cameras, was of the "behind" design
(thus having the vignetting problem) while the Realist 2.8 was a
"between" (no vignetting) design.  (I believe "between" meant the
component in question appears between the lens elements.)  Sorry
I can't be more specific at the moment, but my copy of the Technical
Page is at home and I am not.  I guess I need to leave a copy any
place I am likely to connect to P3D.  ;)  Better yet, anyone who
is interested in stereo photography but who doesn't already have
a copy should order one for themselves!  At the low price of $15,
postpaid, it is a terrific value.  Send your check to Charles A.
Piper, 26810 Fond Du Lac Road, Palos Verdes Peninsula, CA 90274.
Note that proceeds benefit the Stereo Club of Southern California.
Piper's writings originally appeared in "3-D News," published by
SCSC.

Paul Talbot, hoping he doesn't go home and discover he only dreamt
             about reading such an explanation  ;)


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