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1978 ISP COMMISSION V INTER-CONGRESS SYMPOSIUM - STOCKHOLM SWEDEN
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Paper by O. Andrei and E. Cotovanu
(Ihis paper was presented by Dr. Gutu)
"SPACE-TIME PHOTOGRAMMETRIC DETERMINATIONS FOR OPTIMIZING THE RIVER
NAVIGATION"
Discussion of the above paper.
Derrington: How have you made the surface of the water visible in your
preliminary experiments in the laboratory?
Gutu: It is not the water. It is difficult to give the surface of the
water contrast by adding soemthing to the water. We used bits of plastic
which floated on the surface of the water.
Linkwitz: How did you achieve synchronization? At what speed can you
take successive photographs?
Gutu: We have devised and built in our institute a special device to
ensure synchronization. To your second question I can say that it is
about the same as in cartographic photogrammetry.
$$ $-8:9-8 9:956. 6.5.6 S58 6 8 S5 6 6 85 8$ 8$ S 5 S
Paper by G. Würtz - CARL ZEISS JENA
(This paper was presented by G. Voss.)
"ON THE INNER ORIENTATION IN THE FOCUSABLE UMK 10/1318 UNIVERSAL MEASURING
CAMERA OF VEB CARL ZEISS JENA"
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Discussion of the above paper
Oshima: I want to ask you about the distortions. Sometimes with a focus-
able lens the camera can be very sensitive to eccentricity, and not only
the radial, but also the tangential distortion is very important. Did
you try to measure that distortion?
Voss: Yes. The change in asymmetry and in tangential deformations is
stated in the paper. It is less than 2 microns, within the focussing
setting range. To measure this distortion in the factory we used a gonio-
meter. The results of the calibration by goniometer correspond very well
with that which you get when you use panchromatic emulsions. Of course
when you use a goniometer you cannot get tangential deformations because
you can only measure radially. He checked this photographically, and
found that when you measure the radial asymmetry, and this can be derived
from the distortion, and you multiply these values by a factor of 0.4,
you get very good correspondence with the tangentials.
Abdel-Aziz: You mentioned that the lens distortion is within two microns.
what is the actual reliability of this figure? In some cases the un-
certainty due to lack of film flatness could be more than two microns.
Voss: You will remember that when I started to read the paper I said
that Dr. Würtz' investigation related to the camera itself, and not to
any exterior influences, such as film flatness.
Scott: How did you focus the camera at close focal distances? You want
to determine the principal distance at close focus setting. How did you
actually go about determining these?
