Many manufacturers in different countries now produce cameras having reseaux
(not always in conjunction with a glass plate focal register) to assist in corr
ecting for film shrinkage. One camera incorporates an illuminated step-wedge,
a valuable aid to sensitometric control. The super-wide-angle lenses introduced
at the 1960 Congress are now quite widely used, often with infra-red film High
speed inter-lens shutters, operating up to 1/700 or 1/1000 sec. , are also much more
common.
Detail improvements in rectifying apparatus, and domestic production of dodging
printers by Japan, are other developments noted.
A history of the development of military mapping cameras in the USA has been
given by Robert C. Livingston. (Photogrammetric Engineering, Jan 1964) It is
recorded that the KC3 camera, built in 1960, had a European super-wide angle
(120 ) lens mounted in an American-made body. This camera has a platen reseau,
the intersections of which are 0.004" openings filled with lucite for light dist
ribution. It is installed in stabilized mountings for many uses. The most recent
USAF camera is the KC6A, having a 6" f/5-6 American-made Geocon IV lens of
high resolution and distortion less than 8 microns, in a shutter working up to
1/800 sec. ; automatic exposure control is included
Navigation
It seems appropriate to refer to aircraft under this heading. Survey aircraft are
nearly always modifications of standard civil or military types, and suffer in
various ways, such as poor downward and forward visibility, or lack of suitable
space for camera ports,etc. It is therefore of interest to note that a prototype
survey aircraft has been constructed in Poland. A detailed description is not
yet available, but major characteristics are:
Type.
Motors:
Minimum Speed:
Cruising Speed:
Range:
Ceiling:
MD - 12F, low wing monoplane
4 x 330 H.P.
150 Km/hr (93 m.p.h.)
280 Km/hr (173 m.p.h.)
2100 KM (1300 Miles)
5200 m. (17000 ft.)
The use of DO 28 in Nepal, and interest in the STOL for low altitudes, also the
development of a Doppler navigation equipment, is reported by Japan.
ITC , Delft has developed a survey navigation method by combining some new
ideas with general D.R. and visual navigation principles. The method is partly
visual and partly instrumental and is intended to be of particular use over
unmapped areas, flat or mountainous. A special slide rule has been developed
to compute turns leading to predetermined flight-line spacings during flight.
(The initiation of these developments was reported to the 1960 Congress)
ITC has also introduced a course covering the complete execution of survey mis
sions , including navigation over large mountainous unmapped areas,
Canada provided information on Moving Map Display equipment, but it is not clear
whether this has yet been used for survey photography in the usual sense.
Improved navigation telescopes are mentioned, covering 100°, allowing the navi
gator to swing his line of sight from the nadir point to the horizon, and providing
synchronized remote control of camera tilt and drift setting.