Re: [OM] lens "contrast"; keystoning; SCSI card

Subject: Re: [OM] lens "contrast"; keystoning; SCSI card
From: "John A. Lind" <jlind@xxxxxxxxxxx>
Date: Sun, 12 Nov 2000 00:46:18 +0000
At 02:41 11/12/00 , Doris ranted:
>  What IS the "accuracy of the scene", anyway ? Our eyes and mind do not
>function like glass and film. My eyes see muddy shadows. In fact, a whole 
>whopping lot more shadow detail than any camera/film combo.
>  Your argument hinges on the accuracy statement, but
>this is a subjective thing.  We
>interpret a scene, not chain ourselves in slavish devotion to an ideal of
>'accuracy', unless you're a scientific or forensic photographer.
>  Ansel Adams clearly states in his books that the Zone System is not
>designed to merely enslave a photographer to a literal interpretation
>of a scene, but to expand the range of possibilities of expression.

Well said.

Indeed, just as he discusses this in making the exposure, Ansel Adams
speaks of this in his first volume "The Camera" extensively in discussing
the qualitative aspect of optics.  He makes this point, poignantly at the
very beginning, and more elaborately in several chapters later in the
volume.  A camera "sees" and film "records" the world differently from our
eye and brain in both shape and scale.  A two-dimensional image of a
three-dimensional world must be some level of abstract representation or
interpretation of reality.  Thus he introduces the concept of
"visualization" and "image management."

A good example of this:

See this photograph in my gallery:

Now open a second browser window and compare it with this later photograph
which was my TOPE 2 submission:

I visualized what I wanted from the first and actualized it with the second
for TOPE 2.  Had I tilted the lens for the TOPE2 up or down from anything
but dead level it would have very noticeably "keystoned" the image as a
rectilinear that wide should have.  Would it be distortion?  Yes and no.
It would remain an accurate rendition preserving the mapping of angles from
one set of planes (containing the vertical lines) to another not parallel
to it.  However, it would not have preserved the areas (which are not
preserved in this image either).

Which accurately portrays reality?  Both and neither.  I did not
"manipulate" either digitally, other than some minor adjustment of color
balance and contrast range.  The scale of foreground to background in the
first one more closely matches how we perceive scale in the world with our
eye and brain.  It was done using a 50mm lens.  However it lacks the
totality of the venue that can be seen and felt by a human standing there
because the eye and brain scan much more of a venue than a 50mm standard
can capture.  The second captures more of the totality of the venue that a
human would, but its scale of foreground to background is much different
from how a human would perceive it with the eye and brain.

Which is "right?"  Both are; they each are what I intended to do.  The
second employed Adams' "image management" concepts in deliberate use of an
18mm super-duper-wide to create the feeling of a very distant city.  That
was my "visualization," but it's not reality in terms of how a human who
has stood in that exact spot would remember its scale.

Albert Einstein realized this very problem for human scientific exploration
and examination of the universe around us, and the limitations the human
senses have in discerning whether or not what is honestly perceived, is real!

Yes, this is long, but its point is one *cannot* accurately capture all
aspects of reality in *any* image.  Call it the "Heisenberg Uncertainty
Principle of Photography," on several different levels or in several
different dimensions.  It's a matter of the photographer deciding on what
accuracies to retain (some or none), and which to forego (some or all), in
portraying some abstraction of reality to the intended viewer(s) of the
final image.

[Obligatory OM Content]
I am quite thankful my OM bodies and Zuiko lenses enabled actualizing the
different visualizations for both images:  The OM-1n with 50/1.4 MC and the
OM-4 with 18/3.5 MC.  TOPE 4, for which the window is currently open, calls
for an extreme in visualizing an abstraction of reality and actualizing it
in an image.  Not something I am accustomed to doing, but I will give it my
best shot (pun intended).  Not certain either what it will be yet, but
guarantee it will completely stymie all effort of human cognition to
determine what was photographed.

-- John

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