Camera Work: A Photographic Quarterly (1905 (Heft 9))

modern full-toned, full-valued production. The Japanese, whose philoso-
phy of values is much the same as Giotto’s, are able to render even atmos-
pheric effects by merely using the values of the local color.
In another system of values, sometimes employed by the Florentines
and not infrequently by Michael Angelo, the values of the local color are,
to a certain extent, eliminated, and the light and shade exaggerated. The
effect thus produced is most powerful, although at times hard and glaring,
interpreting a mental attitude toward nature which can be expressed in no
other way. The photographer has it largely within his power to render
nature according to this school of values. But, when he does so, he usually
speaks of his results as untrue, which they are not; they are merely untrue
to the Constable and physical version.
With Giorgione and the Venetians is associated a most interesting school.
Giorgione’s few portraits fully express his conception. He proportioned
almost the full gamut of his palette to the head he was portraying, so that
when he came to the black draperies he had left no pigment dark enough to
render the shadows. The strong effect of light on the head is not carried
out on the draperies, the illuminated parts of which are almost as black as
black paint. Yet, psychologically, he was very true. When we talk to a
friend we are impressed with a sense of reality and of light and are barely
conscious of his black coat. And so we remember him; something real,
something made of flesh and bone. From the French and Constable
standpoint Giorgione was true to nature in his values of the head and
false in the values of the whole. Photographers occasionally employ the
Giorgionesque philosophy of values, the work of Steichen being an excel-
lent example.
Some schools of painting in their interpretation of nature take into
consideration certain physiological habits of the eye. These, being too
many to enumerate here, I will merely touch upon one, very important in
influencing our judgment of relative luminosity — the involuntary habit of
the iris of the eye of contracting and dilating. When the eye is directed
toward a source of strong light, the iris contracts over the pupil, allowing a
small quantity of light to enter and fall on the retina. When the light
lessens the pupil dilates and more light enters. This is a provision of nature
to protect the delicate nervous system of the retina from too strong light, as
well as to admit sufficient light when the source is weak. The pupil is
capable of contracting to an area of about one-fiftieth of its maximum
expansion, but the mind being unconscious of the movements of the iris, all
possibility of judging the strength of the light is taken away from us.
When we suddenly emerge from a dark room into a strong out-door light,
we feel dazzled, but in a few moments the pupil, and also certain nerve-cells,
so accommodate themselves that the light appears no stronger than it did
indoors. As the day wanes we are unconscious of it, the pupil continually
expanding and following the fading light. But the power of accommodation
of the eye is limited. Very strong sunlight is always painful and in the
dark we see with difficulty.