routines more efficiently and the perfecting of electronic
correlation to permit a minimum of human intervention. The
flexibility of computer control permits a variety of input
materials to be used. It also has greater potential accuracy
provided the input data, such as pass point measurements and
distortion characteristics of the photography, are determined
more precisely.
73. Theoretically, the all digital approach appears to
offer the greatest promise for mapping in the future because
of its even greater flexibility and potential reliability.
Development costs will be extremely high and, at the present
state of knowledge, the amount of risk involved in developing
a competitive cost effective system is reasonably high. It
has ultimate potential for operating at extremely high speed,
providing high accuracy results, handling poor photographic
quality, accomplishing the additional mapping functions of
automatic image (map detail) recognition, compiling line maps
directly, and preparing numerical maps for data transmission.
74. It will be noted that developments in automation
have been sponsored almost wholly by the U. S. Army and the
U. S. Air Force. While economy plays an important role in
utlimate decisions regarding which approach to employ, con-
siderations of speed, flexibility and reliability cannot be
ignored by the military. The military is interested in a
high speed mapping system, especially one that can use a
variety of input materials which may already be available
rather than one that requires photography with a specific
camera system.
75. The Pictomap is another approach to producing a map
product in a minimum of time. The orthophotography or
orthophoto mosaic as produced by automatic map compilation
equipments contributes to this time saving and results in a
more effective map substitute than rectified aerial photography.
76. Some of the promises of automatic map compilation are
beginning to materialize. Contours have been compiled on computer
controlled plotters at "C" factors equal to or higher than con-
ventional stereoplotters in a fraction of the time required by
such conventional stereoplotters. The quality of orthophotos
produced by the electronic systems is sufficiently high for
extracting line map detail and as map substitutes as well as
for a multitude of other uses.
77. The quick production of high quality orthophotos may have
considerable significance in the more general adoption of the ortho-
photomap or the Pictomap as an end product. Their use for map
revision is a foregone conclusion. Their metric qualities permit
direct comparison and revision when the old map, produced on a
transparency and at the same scale, is overlaid on the orthophoto.
Acceptance of the orthophotomap for such uses as geology, forestry,
agonomy, hydrology, in addition to its use as a map substitute
is becoming more widespread. The ability to mosaic a complete
map sheet on automatic mapping equipment will result in a high quality
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