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In Defense of Testing
by Phil Davis
Arguments about art photography and religion have at least two things in
common: they’re both likely to be based on supposition, wishful thinking,
prejudice, and blind belief — rather than on fact — and they tend to
generate more heat than light.
This is understandable because there really isn’t much factual basis for
assertions about either art or religion. Discussing either can be
entertaining, and occasionally inspiring, but sooner or later we have to
recognize that there are no definitive answers, and one person’s opinion —
no matter how unpopular it may be with the majority — is just as valid an
any other’s. We sometimes find this difficult to accept, though, and if a
religious argument becomes irrational and turns ad hominem it can escalate
into something approaching a holy war — as witness the Crusades. We can be
thankful that art arguments haven’t reached these ridiculous extremes, at
least not yet.
There’s no reason why they should, either. Although we’re not likely to
learn anything specific from them, debates about photography’s rather
tentative status as an art form, or about the merits of any given
photographic image, can be stimulating and insightful if tempers are
controlled. In that sense the spirited bull-sessions that we enjoy so
thoroughly are both valid and valuable — as long as they deal with concepts,
and keep opinions from masquerading as facts. After all, facts aren’t really
“facts” unless they’re factual, and in that case there’s no point in arguing
about them. For sonic reason, though, we seem to love to imbue every aspect
of this medium with mystery so that the distinction between fact and fancy
tends to blur. When that happens it’s really counterproductive.
Unlike the other visual arts, photography straddles the fence between the
separate areas of art and science. The part of photography that deals with
subject selection, visualization interpretation expression, and image
appraisal, is clearly subjective. These are aesthetic considerations. They
have no valid laws, nor any binding criteria. In this unrestricted area,
opinion, whimsy and self-expression rule. Science has no business here.
On the other hand, the part of photography that involves such things as
hardware function and materials’ characteristics, is rigidly governed by
physical and chemical laws that are not debatable. This is the scientific
realm. These things can be measured and their characteristics identified,
Rumor, conjecture, superstition, and wishful thinking have no business here.
Of course we’re certainly entitled to our opinions about the suitability of
the tools and materials we choose to use, but the fact that we may like or
dislike a certain film, for example, is objectively irrelevant, and does not
in any way affect, or necessarily even relate to, that film’s actual
characteristics, Unfortunately it’s tempting to overlook this and make rash
pronouncements about materials’ characteristics, based on simple observation
of print results or on haphazard, experimentation; which strongly suggests
the possibility that those conclusions will be misleading and that the
materials may not behave as expected when used in the field.
To avoid these unpleasant surprises, many photographers — especially those
who choose to work in black-and-white with large-format cameras — test their
materials in one way or another Most follow the traditional zone system test
methods that involve in-camera exposure of the test films, more or less
arbitrarily assigned film development times, a standardized printing method,
and eye-match appraisal of the print results.
When done with care these tests can provide general guidance for the field
use of the materials, but these empirical methods are neither very reliable
nor very efficient for a number of reasons: for example, there’s no
convenient way to calibrate the individual increments of film exposure with
any accuracy. In addition, although visual appraisal of print grays can
provide some indication of the overall effect of the processes, it doesn’t
permit very reliable analysis of the characteristics of the individual
materials. In other words, we’re not likely to know for sure what we’ve done
to the materials, nor can we know for sure how they’ve reacted. Finally of
course, this approach to testing is very wasteful of both time and
materials.
Traditionalists defend this testing method — some vehemently — on the
grounds that involving the camera in the test simulates the conditions of
practical use and is, therefore, not only convenient but desirable,
Similarly, they are apt to argue emphatically that, after all, the purpose
of this whole thing is to produce prints, so appraising print values must
therefore be the most appropriate way to judge the materials’ performance.
In fact, that’s a technical non sequitur. These traditional testing
procedures can’t supply material-specific information any more than driving
your car around the block can inform you about the comparative quality of
your motor oil, You can obviously tell whether the car runs satisfactorily
or not, but you can’t know for sure what part the oil has played in that
performance. There are simply too many unrecognized or uncontrolled
variables in the procedure; there is no accurate way to quantify the results
of such subjective tests, and you have no logical basis for assuming that
the conclusions drawn are valid.
The one feature that makes the traditional test procedure) as reliable as it
is, is the “standard printing time” convention. By eliminating print
exposure as a variable in the process it becomes possible to "measure"
negative minimum density (approximately) so that some estimate of effective
film speed can be made; and it standardizes the print image densities
sufficiently so that it’s possible to get a ball-park estimate of the
effects of film development variations. In other words, the "standard
printing time" and eyeball comparison of print grays combine to serve as a
sort of make-shift densitometer. This ingenious concept made it possible for
Ansel Adams to introduce into the photographic process a degree of control
and predictability that was ahead of its time; and it has served a great
many photographers very well.
But times change and facilities improve. No doubt many photographers will
remain convinced that the popular zone system test methods are "perfect" (as
one staunch traditionalist has declared), but we can now get more accurate
data — and much more of it — in much less time, with minimum waste of
materials, by isolating the materials tests (to eliminate a variety of
uncontrollable variables) and reading the resulting test samples,
objectively, with densitometers.
Although densitometers were virtually unobtainable in Adams’ day, and are by
no means standard items of equipment in most darkrooms even yet, they are
increasingly available on the market and prices are coming down, It’s even
possible to adapt most spotmeters to make useful density readings; so almost
any competent photographer can now benefit from the efficiency economy and
reliability of objective testing, even on a severely limited budget.
"Knowledge is power," they say. There’s no doubt that more accurate
information about how materials behave in use can be helpful; and this goes
well beyond the simple calculation of more precise exposure or development
times.
For example, when we can identify image gradation differences that may be
produced by various combinations of materials, we have sensible criteria For
choosing the film, developer, and paper that will complement each subject
type most appropriately. We can even determine when "misuse" of some
material — such as abnormal exposure and/or development of the film — may
have useful potential, and deliberately apply it to emphasize some desirable
quality of the image, These are subtleties of control that the traditional
empirical testing procedures can’t provide.
I’m well aware that many photographers will disagree with me, and insist
that objective testing methods dehumanize the process, inhibiting creativity
and stifling freedom of expression. But I believe the opposite is more
likely to be the case; better understanding should really expand creative
options and lead to greater freedom, not less. Certainly knowing what your
materials can or can’t be made to do should make visualization easier and
more effective, and minimize the possibility of serious miscalculation.
Ultimately whether we like it or not, we can’t avoid contact with technical
details in photography, so why fight it? Let’s put science to good use in
the service of our art, not in conflict with it. Objective testing frankly
acknowledges the existence of the two faces of photography — the technical
and the aesthetic — and clarifies the distinction between them to reduce
confusion, improve control, and increase efficiency. It’s hard to see why
any thoughtful photographer should object to that.
Phil Davis is a teacher, author of several texts and articles on
photography, and holds workshops involving sensitometric techniques. His
book Beyond The Zone System outlines a basic set of sensitometric tests that
accurately and quickly evaluate photographic materials.
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