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The generation of tilted perspectives from vertical
photographs can be accomplished on the printer at present,
but only a limited number have been generated. More of
this will be accomplished as part of the in-house experi
mental work being conducted.
The unique analytical transforming characteristics
of the printer will be the basis for experiments with
radar and infrared imagery. In the case of IR imagery,
the inherent geometric distortions are due to the scanning
method, wherein the scanner runs at a constant angular
rate while the imagery is recorded at a constant linear
rate. The characteristic image shows compression at the
edges. There are other distortions to be considered, but
these distortion corrections should be only a bit more
complex than those now done with panoramic materials, and
can be handled with software.
In a like manner, Side-Looking Radar imagery will be
experimented with. Here the primary distortions are due
to terrain relief and flight line and attitude anomalies.
Once these are reasonably defined, plane and orthorecti
fication can be accomplished.
Strip camera imagery represents a recording that
contains distortions along the flight line direction,
due primarily to attitude changes. The imagery essentially
has a principal point for each elemental line of exposure.
If the locus of these principal points can be determined
the imagery can be rectified on the Off-Line Printer.
With the addition of terrain data, the imagery can be
orthorectified.
The above possibilities are cited in order to
emphasize the great flexibility of the Off-Line Printer,
based upon its ability to position any chosen elemental
area of the input record at the optical axis, under
computer control.