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.
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.
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’
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.
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
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.
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.