viii INTRODUCTION
overboard-and stereo does not seem to have been harmed by
the fact. Stereo used to be reserved for very carefully made expo-
sures of subjects selected with equal care, the new stereographer
blithely shoots go or 60 shots in an afternoon.
All of this has a most important bearing upon the development
of the new art, and certainly it must affect our approach to the
subject in any kind of discussion. Photography is one of the most
conservative of the common arts, foolishly so most of the time.
The writer can remember the senseless struggle of the glass plate
advocates (which means about gg percent of the serious photog-
raphers, professional and amateur) against the encroachment of
the sheet film. Today we see the stereo Old Guard tearing their
hair and clad in sackcloth and ashes as one after another of their
cherished idols falls under the onslaught of the enthusiastic “new
stereographer.” But with this Old Guard numbering considerably
under 1000 and with the new legion growing at about 20 to 30
thousand every year, the newcomers, fortunately for all con-
cerned, are going to have things their own way.
The stereographer was once very proud of his theoretical
knowledge, whether it was accurate or not, and he used stereo-
scopy only as a stepping stone to elementary, very eIementary
stereogrammetry, and to him “stereo” was far more grammetric
than scopic.
Stereoscopy as practised in stereography is a matter of produc-
ing a desired visual effect. The appearance is the ultimate goal of
the whole process. Therefore, as far as stereography is concerned,
errors, mistakenly called “distortions,” if they are invisible simply
do not exist. I recall one enthusiastic young mathematician who
wrote about PO pages pointing out that a certain stereo tech-
nique was not distortionless as claimed, but involved two serious
distortions. “Of course,” he added, “these two distortions neutral-
ize each other and so are not apparent, but they are there as I
have proven!” He simply could not understand that stereo-
scopically, the invisible is non-existent. He was delving into the
realm of stereogrammetry.
Another, this time a stereogrammetric technician, produced an
involved mathematical dissertation proving the inevitability of
distortion produced by the “magnification” of the viewer. He