plastic plates with a grass contrast. The field 
was photographed with both reseau cameras 
using two different aeroplanes at the scales 
1:11000 and 1:5500. Several different methods 
were used, for the elimination of systematic 
errors. The measurement and utilizing the reseau 
crosses had only small influence on the final 
results (PP 1/21). 
Mr. Hakkarainen: Jamijarvi Test Field 
The test field is 200 km northwest of Helsinki. 
There are two point nets lying one inside the 
other. The smaller field is 800 x 800 sqm consisting 
of 187 points and the larger field correspondingly 
2x2 sqkm consisting of 140 points. All points 
are levelled. The accuracies are in x,y X2 mm 
andt5 mm correspondingly. The field was 
photographed with both reseau cameras at scales 
1:5000 and 1:10000. Mr. H. Salmenperá has 
computed the radial and tangential distortion of 
the cameras. These preliminary results show the 
same type of results as the determinations with 
HUT goniometer. 
Dr. Ziemann: Sudbury Test Field 
Dr. Ziemann first explained shortly the structure 
of this Canadian test field. All points are levelled 
to + 2 mm. The x,y accuracy is + 1 cm. The tar- 
gets are mostly 30 x 30 sqcm white plates, fit- 
ted on the rock with bolts. The rock is also used 
as contrast. The field has been photographed at 
scales 1:8000 and 1:15 000 with the reseau ca- 
meras. 
Dr. Merchant: Casa Grande and Mt. Graham 
Test Fields 
Ohio State University has a mountaineous 3-di- 
mensional test field at Mt. Graham. The maximum 
difference in height is 1100 m. With the reseau 
cameras also the flat test field of Casa Grande 
was photographed. This field has been planned 
for small scale flights. The targets are black tri- 
angle groups on white sand. 
Presented Papers 
The session concluded with brief reviews of 
Presented Papers by their authors: 
Author: Mr. K. Ellenbeck (F.R.G.) 
Title: Untersuchung zum stochastischen 
Verhalten von Reseauaufnahmen 
(PP 1/11) 
The main result was, that the geometrical noise 
of reseau photographs studied was +3 um. 
Author: Dr. L. N. Wassiljew (U.S.S.R.) 
Title: Kalibrierung der Messkammern un- 
ter Verwendung der Luftbilder eines 
Prüffeldes 
Dr. Wassiljew considered the test field calibration 
be more reliable than the laboratory calibration 
because of environmental factors affecting the 
stability of the aerial camera. 
The session was adjourned. 
86 
Thursday, July 15, 1976, from 9.00 to 10.30: 
Session 3 of Commission | 
Topic: Space Imagery 
Chairman: Dr. E. P. Welander (Sweden) 
Invited Paper 
Author: Dr. F. J. Doyle (U.S.A.) 
Title: Space Photography (IP 1/06) 
Presented Paper 
Author: Dr. A. Colvocoresses (U.S.A.) 
Title: Status Report on Landsat as a 
Source of Cartographic Data PP //05 
Panel Discussion 
Topic: Space Imagery 
Moderator: Dr. F. Doyle (U.S.A.) 
Panelists: Dr. L. Kashin (U.S.S.R.) 
Mr. R. Ondrejka (U.S.A.) 
Mr. J. Denègre (France) 
Mr. P. Mott (U.K.) 
Mr. G. Petric (U.K.) 
The Panel Discussion was led off by Dr. Kashin 
who spoke on the use of space imagery in the 
U.S.S.R. He mentioned Solyut and Soyuz, noted 
that cartographic and photogrammetric imagery 
at scales of 1:2 500 000 and 1:1 000 000 had been 
obtained in several spectral bands, and that 
the imagery was used for agriculture, geology, 
and forestry. Mr. Ondrejka continued with a 
rather provocative proposal for GEOSAT, a system 
which would have stereo capability and a 10- 
meter ground resolution and would include multi- 
spectral, thermal IR, and SLAR and color photo- 
graphy capability. He noted that such a system 
would have industry support. Mr. Denègre spoke 
further on Spacelab, noting that a convergent 
system might be employed to obtain stereo 
coverage, and that the system should be capable 
of supporting map compilation at 1:100 000 
scale or even 1:50000 scale. Mr. Mott talked 
about his experiences with Skylab imagery for 
mapping a portion of Nepal. He was able to 
contour at a 200-meter interval. He noted the 
desirability of stereo coverage and suggested 
that a laser altimeter be employed. He suggested 
that space imagery might be used to generate 
ground control, and he stated that he had used 
Landsat imagery for flight planning. Finally, Mr. 
Petric indicated that contouring was the main 
problem with space imagery. He was in favor of 
Spacelab, and he encouraged LS.P. to give it 
support in order to overcome political problems. 
Thursday, July 15, 1976, from 10.45 to 12.15 
Session 4of Commission | 
Topic: Remote Sensing 
Chairman: Mr. W. A. Fischer (U.S.A.) 
Working Group Report 
Authors: Mr. W. A. Fischer (U.S.A.) 
Mr. W. R. Hemphill (U.S.A.) 
Mr. A. Kover (U.S.A.) 
Title: Progress in Remote Sensing 1972 
—1976 WGR 1/04 
"