P3D Stereo Nomenclature and some Glossary History 2/3

[abram klooswyk <abram.klooswyk@xxxxxx>]

The Deutsche Industrie Normen (DIN), the German institut for
standards, has published a number of guidelines for stereo terms.
They started in 1956 with 4531 Blatt 1, Stereoskopie
(Raumbildwesen), Begriffe. This was only an alphabetic
glossary of some 40 terms. (Begriffe = concepts or terms).
In 1963 they published a special list for anaglyph terms
(DIN 6170 Blatt 1)
In 1971 a draft revision of DIN 4531 Blatt 1 was published,
this was a much expanded list, which also adopted a systematic
order (1 Images, 2 Equipment, 3 Image separation, and so on).
In 1974 a new final form appeared as DIN 19040 Blatt 8:
Photographie / Allgemeine technische Begriffe fuer Stereoskopie
(Raumbildwesen).
Then Fritz Waack got the idea to translate the DIN standard
in English, and he send the result to W.C. Dalgoutte, who was
the editor of the Stereoscopic Society Bulletin (UK).
Bill Dalgoutte had published an English stereo glossary in the
Bulletin in 1967. He of course found many translation errors
in Waack's draft, but the German standard contained, in his
opinion, also quite a number of conceptual errors. He feared that
the German standard should be the basis of an international
ISO standard, and wrote on the errors to Waack (Feb 1975)
and in the Bulletin.

The first congress of the International Stereoscopic Union (ISU)
was held in Wageningen, the Netherlands, in May 1975.
Unfortunately Dalgoutte was not attending, but Fritz Waack and
many other interested stereoscopists were. At my proposal a
committee for stereo terminology was formed, composed of
Dalgoutte, Ferwerda, Olsson (Sweden), Soulas (France), Waack,
Wing (Paul, USA) and myself.
There was mail exchange between the members of this committee,
but in the end no agreement was reached.
In fact most members thought that the Dalgoutte list worked
well enough, but the errors in the German list were in an
official document (hard to revise), and the systematic order
of the DIN was in several ways artificial. After 1978 the
committee was sleeping...

A new German stereo terms standard was published in 1979:
DIN 19040 Teil 8  (apparently the way of numbering also was
revised each time).
In subsequent years Waack translated this revised form of the
DIN in English and French, with help from Dalgoutte, Marc
Fontannaz (Switserland) and Pierre Tavlitski (France), but
Waack still did the final editing (1986). This was not adopted
as ISU glossary however.
Most of the former DIN errors were removed from this last
revision, probably due to Dalgoutte.

A remaining doubtful item was the "Stereoskopische
Tiefenzone": "Die ~ ist der beidäugig ohne merkbare Änderung
der Akkomodation physiologisch verschmelzbare Tiefenbereich
zwischen zwei verschiedenen weit erntfernten Raumpunkten."
This was translated as: Stereoscopic Depth Range - Binocularly
fusible depth range in natural vision, without significant change
of accomodation between two points of different distance".

It is hard to believe this was written by Dalgoutte. In my opinion
the meaning is obscure, and if it means anything at all it is
probably in error or irrelevant for stereoscopy. (Note: the "in
natural vision" is not in the German text)

Abram Klooswyk