The Wonders Of Image Degradation
Saturday, September 13, 2014
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| Caitlin Legault |
Yesterday I took my venerable Dresden-made (when Dresden was in the Russian Occupied Zone) Pentacon-F to be repaired by Horst Wenzel. He looked at the camera tested the functions of the 50mm Zeiss Tessar lens and informed me that the shutter just needed to be cleaned and re-lubricated.
As I wrote here,
repairing the camera, a waste of money in Wenzel’s opinion, has something to do
with my allegiance to inanimate objects that have served me well. I felt guilty
looking at it on my den bookshelf knowing that it had a faulty shutter and that
unlike in other countries here we have in Vancouver
a stellar repairman.
Its beautiful Zeiss
Tessar f-2.8 lens probably could not compete in sharpness with my new Fuji
X-E1s exotic aspherical zoom lens. Nor could it compete with a early 80s
vintage Pentax M 20mm wide angle that I have kept because of its remarkable
lack of apparent distortion. It is as rectilinear as a wide angle gets.
Since the early 80s
the main lens in my working collection has been a floating element 140mm Mamiya
lens for my Mamiya RB-67 Pro-SD. I have two of them. Some years ago when I was
about to take pictures of Raymond Burr the mainspring went. I was forced to use
a less sharp 90mm that made Burr look fatter than he was. I vowed never again
to have this happen to me so I purchased a second 140 lens. Wenzel has a spare
main spring spirited away in his repair shop.
For years I have
maintained that all photographs (and particularly portraits) have to be sharp. If
you cannot see individual eyelashes, throw the negative or slide away. The
exception of course is when the photographer intends for the picture not to be
sharp for some particular motive. Another fine exception is the look of old optics, even optics that were sharp in their time. I used a 1953 Leica IIIF for these pictures that have a look unmatched and different from anything that I might use now.
To this day I question
autofocus lenses and the idea of an automatic follow focus lens does not apply
to me as I never shoot basketball, hockey or football.
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| Horst Wenzel |
I know that the
sharpest f-stop of almost any lens is somewhere (usually halfway) between its
minimum and maximum aperture. I know that bracing the camera with a tripod is a
sure way of maintaining the inherent sharpness of a good lens. I know that the
flutter of a reflex camera’s mirror can degrade the image at a slow shutter. With
my Mamiya I always use its lens mirror lock mechanism.
So much for sharpness
via the camera.
In my fridge I have 30
rolls of the sharpest most detailed film ever made. This is Kodak Technical Pan
in 120 format. So much for sharpness via film.
I also know, and this
is increasingly a decreasing factor for
most photographers that the best test for sharpness is the detail of an actual
print be it a darkroom printed photograph or a well executed digital giclée or
light-jet print. Looking at pictures on a monitor (to me) is a waste of time.
How fast will that car
go? Don’t give me numbers. Drive it. I think that applies to photography, too.
It was a few days ago
that a tweet by my friend Tim Bray caught my eye. In his tweet he linked it to
a man who writes about the wonders of a medium format camera that has an aftermarket
digital sensor attached. There are even more expensive dedicated digital Hasselblads.
I read the article,
obsessive, by a man (Zack Arias is his name) obsessed with detail, sharpness, colour
saturation and the ability to crop minute parts of an image and still render it
all in close perfection.
I read the article and
I smiled as I seem to be headed into the opposite direction with my Mamiya
RB-67 Pro-SD described as a tank by someone in the comments section of the
essay. He further says that at the end of the world only cockroaches and RB-67s
will survive it!
Case in point in my contrary ways is the
story behind the image here and its almost identical but not as dramatic
companion negative which was shot one click before.
My goal was to attempt
to imitate the wonderful (paradoxically very sharp) wet plate portraits taken
by Mathew Brady in his New York City
studio in the early 1860s. His lighting consisted of a very large skylight.
Having some idea of the fact that sensitized plates (like all film, video tape,
and even modern digital sensors) were more sensitive to the blue light coming
from skylight, Brady tinted his skylight glass blue.
Since I no longer have
a studio with a high ceiling I mounted a large softbox light that is five ft by
6 ft on a boom light stand. This meant that I could suspend the light high and
pointing down on my subject (Caitlin Legault) to give the feel of skylight. Generally
I use a 3 by 4 softbox very close to my subject’s face so half the face is
always in some shadow. Behind Legault I put up a red backdrop (the colour
unimportant as I was going to shoot it all in b+w). I had all this in a shady
part of the garden and I set my camera shutters to expose the existing light to
one stop under the correct exposure. The flash was set at f-16 both with two
rolls of Ilford FP-4 Plus IS0 100 and two rolls of Kodak T-Max 400 (the images
you see here are the T-Max).
I was able to keep the
f-16 exposure with the two different rolls by controlling the output of my
stable Visatek monolight flash.
The less dramatic
image is almost a straight scan (an Epson Perfection V700 Photo scanner). I
scanned it dark and in the warmish tone on purpose.
For the second image, I
placed the negative emulsion down on the glass with no holder. This means that
the negative curled on the sides and it was not completely flat. On top of the negative
I placed a sheet of my letterhead stationery. I left the scanner top open and I
scanned the negative from the bottom as I would scanning a 8x10 print. The
resulting image I then reversed (as it appeared as a negative) in Photoshop.
The paper adds to
measures of degradation. Because the paper was in close contact with the
negative, the scanner “sees” some of the flaws and texture of the paper. The
light of the scanner, instead of penetrating the negative fully it bounces off
the paper and back to the scan. That reduces the contrast.
It seems to me that so
mush emphasis this day in photography lies with the technical aspects of the
gear used and there is less on the wonder of an image and how it affects us
when we see it without having to delve on all those pixels and MOS sensors,
etc.
