- 3 -
3) Two spectroscopic plates exposed with a cone mounted in the
camera body when compared with cone calibration data prove
the cone to be mounted free of strain and the calibration
reliable for the assembled came ra system.
4) The well-aged KC-1 aluminum platen has been resurfaced such
that it is now plane over the 9" x 9" format area within 0. 00020"
(5 microns). Air gauge measurements of the deviation of this
surface from a true plane are included in the calibration report
in a form which shows the contour of the surface.
5) The new altimeter capable of recording altitude to 80, 000 feet
replaces the previous one.
These are the features of the KC-1B, now a mechanically and photographi
cally reliable camera capable of first order mapping accuracy; a camera
which has produced good black and white photography under a wide
range of environments. In effect, a dependable workhorse.
BASIC REQUIREMENTS OF MODERN MILITARY MAPPING CAMERAS
While in the general case the bulk of work may be done most efficiently and
inexpensively with a husky workhorse, the more difficult and faster tasks
will require the capabilities of a racer. For mapping cameras, both
commercial and military users list among these "greater capabilities" a
high resolution lens with clean, sharp images, image motion compensation,
and automatic exposure control.
The lens should be a fast one - as cartographic lenses are rated - and color
corrected through the visual and near infrared range, such that it is capable
of using to advantage the new high speed, high resolution color films which
have supplied the photogrammetric gains Swanson and Smith have noted in
their various papers. Distortion for all colors must of course be negligible.
That these requirements are not impossible to attain is attested by the latest
modifications of the Wild and Zeiss 6-inch wide angle lenses.
Military users with their high speed vehicles have long employed both image
motion compensation (IMC) and automatic exposure control (AEC) in recon
naissance photography, the former to reduce image blurring and the latter
to assure correct exposures. With specific consideration for geometric
problems, there would be no reason why both factors would not be equally
valuable in improving mapping photography. With these additional requirements
defined, investigations and research projects naturally followed.