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Carman is a fellow of the Optical Society of America, a member of the
Canadian Institute of Surveys, and a member of the Canadian Associates of
Physicists.
Carman summarizes his present study as follows:
Angular vibration of aerial survey cameras is a major factor limiting image
sharpness, either directly or indirectly. The effect is direct if a shutter
speed is chosen at which image motion due to vibration significantly reduces
sharpness. It is indirect if, to avoid blurring due to image motion, a
high shutter speed is chosen and this high shutter speed necessitates the
use of a large lens aperture and/or a high speed film, either or both of
which reduce system resolution.
Measurements of vibration of modern air survey cameras in a variety of
aircraft over the last few years have shown maximum angular velocities in
the range 20 to 50 mr/s (4 to 10 mm/s image velocity at the film). To limit
image motion due to vibration to 15 um requires shutter speed not slower (9
than 1/270 to 1/660 s. Two comparisons are informative. 1) Image velocity
due to forward motion in high altitude photography is typically 1.2 to 2.2
mm/s. 2) Measurements made thirty years ago on reconnaissance camera
mounts showed 20 mr/s maximum for a standard mount, and 2.5 mr/s for an ex-
perimental mount.
According to Carman: if survey mounts could be developed to consistently
reduce maximum angular vibration velocities to 5 mr/s or less, vibration would
cease to be a practical limitation in present conditions and system resolu-
tions could improve by as much as 407.
Juhani Hakkarainen received his PHD from the Helsinki University of Technology,
Finland, his dissertation on thesis covering laboratory and correlated
flight tests of photographic image quality and camera calibration.
Hakkarainen has conducted research on photogrammetric sensors, testing and
calibration procedures, and has taught photogrammetry at the Helsinki
University of Technology. He is now professor of Photogrammetry at the
Finnish Geodetic INstitute where he will continue his research. (9
Hakkarainen's plans, in assisting WG-3, will extend his image quality
studies so that the environmental effects on image properties can be de-
termined. In order to accomplish this investigation, it is planned that
the Malmi test field in Finland will be enlarged to accommodate higher
flight altitudes. Additional targets of different sizes and types as used
in analytic photogrammetry will also be employed. Lower contrast targets
will be added to the higher contrast ones of the 1973 tests, contrasts of
1:3 and 1:10-15 being considered because of their "natural" values.
Five or more transducers will be installed at different parts of the camera,
and as the external and ambient environments are monitored, the temperature
and pressure of the camera will be recorded.
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