262 THREE-DIMENSIONAL PHOTOGRAPHY
phers. The usual comments upon the attractiveness of the scene
were made, but no criticism was offered. Then they were asked
to point out any visible differences. None did so. Then it was
explained that the distances within the picture were condensed
by two, and by four, compared with the standard. Still only a few
even tried to classify the three prints, and all who tried failed. It
would appear quite obvious from such experiments that the seri-
ous distortion of the wide base, and the insistence upon the nar-
row base have little factual foundation.
It must be admitted that the writer was astonished by the result
of the test. It seemed incredible that the four times base should
not have been seen to be abnormal. Experienced stereogaphers,
of course, would have detected such gross exaggeration.
If there is no foreground object which requires more than about
six to eight prism diopters convergence, and if the mounting is
based upon homologous separation rather than the standard cam-
era negative format, the really valid arguments against hyperstereo
disappear. It might be added that every competent stereographer
watches both factors in every print he makes.
FLAT STEREOGRAMS.-EVerY year there are hundreds of stereo-
grams made with excellent stereo cameras by competent stereog-
raphers which are not at all stereoscopic. These are views of
distant scenes, particularly in mountainous country where the
subject matter is of such huge dimensions that to get it upon the
film at all demands a great distance between subject and camera.
When such a subject is stereographed under normal condi-
tions, the distant subject lies beyond stereo infinity and becomes
just as flat as in a planar photograph. To compensate for this, the
usual procedure is to include some object in the immediate fore-
ground. The classic foreground subject is a human figure looking
toward the subject. Of course this figure, by its position and its
relief, takes upon itself the major importance of the composition
so that the true subject is not only flat, but sinks to the level of
an accessory to the truly insignificant foreground.
The only solution is to use such a base that the true subject
takes on realistic depth, and is then permitted to make up the
pictorial composition without the use of the irrelevant foreground
figure,
This is the practice which is condemned by classic stereo pro-