1.1 Program of the work performed within
the Intercommissional Working Group
The program of the work, performed during the period
1964 through 1968 has primarily been guided by the resolu
tions from the Lisbon congress in 1964, where the working
group was established. It is a continuation of the work
from similar working groups, the reports of which were
presented at the congress in London 1960 and Lisbon
1964, see references 3: 5 and 3: 2. Next, the most important
resolutions from the Lisbon I.S.P. congress will be quoted
for the work of the group.
Commission I
Resolution No. 3. Stereoscopy
The Congress has noted with regret the very limited
amount of research work being done on stereoscopic vision,
as this is fundamental to much of photogrammetric plot
ting. Commission I is requested to work closely with other
Commissions of the I.S.P. and in cooperation with medical
authorities, to encourage research work on stereoscopic
vision.
Resolution No. 4. Accuracy of Photogrammetric Data
Photogrammetry and photo interpretation are founded
upon the geometrical and photographic properties of the
basic photographs and their copies. For the sound develop
ment of the two activities mentioned, it is therefore neces
sary that the basic geometrical and photographic qualities
are kept under good control and be subject to detailed
specifications and tolerances. In particular, the numerical
data of geometrical properties of the image (the interior
orientation, the image coordinates etc.) and photographic
properties (speed and gradation of the emulsion, color
sensitivity, contrast transfer data) must be checked under
real operational conditions and tolerances for the possible
discrepancies must be established. For such tolerances it
is necessary that the accuracy (in the real sense of this
word) of basic test measuring procedures be carefully
determined from calibration procedures. A close coopera
tion with Commission II in this particular problem is
recommended. The terminology of basic concepts as
treated in Commission VI should further be taken into
account.
Commission II
Resolution No. 3
A thorough and comprehensive study of photogram
metric instruments should be made in order to devise a
system for their classification which will be representative,
effective and non-controversial.
Resolution No. 5
The basic geometrical quality of instruments, materials
and methods should be investigated under operational
conditions, particularly in connection with “controlled
experiments”.
Resolution No. 6
Manufacturers of instruments and materials are re
quested to furnish such information about the geometrical
quality of their products that tolerances can be established
according to ordinary principles of theory of errors and
statistics. The confidence coefficient should be ordinarily
set at 95 per cent.
Commission III
Resolution No. 1 b)
The addition of a new field of interest:
study of the sources of errors in aerial triangulation and
of their propagation in the strip. This study should include
in particular the effect of errors in reconstructing the
bundle of perspective rays.
Commission VI
Resolution No. 2
It is proposed that Commission VI should continue the
work to stabilize the terminology for theory of errors in
photogrammetry. Contact should be taken with statistical
and other international organizations in the science of
measurement in order to try to arrive at a common glossary.
Until a common glossary is agreed upon it is proposed
that the actual glossary presented at this Congress be
accepted.
Moreover, reference is made to the Resolutions No. 2,
3, and 4 of Commission II from the I.S.P. Congress in
London 1960.
2 a) All information on accuracy should be expressed in
clear and well-defined terms. This information should be
combined with data about its reliability, e.g. by giving the
number of redundant observations.
b) It is recommended that a glossary of the terms and
expressions used in the theory of errors should be prepared
in the principal languages and agreed upon by national
institutions for international usage.
3. It is desired that principles for the establishment of
tolerances and specifications for instruments and methods
in photogrammetry should be worked out. For such pur
poses it is necessary that the sources of errors should be
carefully investigated under real working conditions. More
attention therefore, should be paid to theoretical and prac
tical investigations of the fundamental operations of photo
grammetry.
4. In order to compare the results of different theoretical
and practical investigations into instruments and methods,
it is suggested that the observations are adjusted according
to the method of least squares.
At the between-congress meeting in Bad Godesberg,
Germany in April 1966 the program of the Working group
was further discussed and some more detailed recom
mendations were made. From the proceedings of Commis
sion II the following statements are quoted.
“Diese Arbeitsgruppe, deren Tätigkeit auch für die
Kommissionen I, III, IV und VI von Bedeutung ist, soll
weiterhin von der Kommission II betreut werden. Sie
wird die Grundlagen behandeln, auf denen die Photo
grammetrie aufgebaut ist.
a. Die grundlegenden Vorstellungen und die Termino
logie für die Qualitätsfragen der Photogrammetrie müssen
geklärt werden. Bei dieser Weiterführung der bisherigen
Arbeiten ist die Zusammenarbeit mit allen Mitgliedern der
I.G.P. notwendig und erwünscht.
Ferner sollen die grundlegenden Operationen der Photo
grammetrie im Hinblick auf die Qualität untersucht werden.