e 
u, The contour generator also contains provisions for 
emphasizing every fifth contour. An emphasis signal is derived 
from the model-elevation signal in the computer and is used to in- 
crease the printing intensity ofthe video signal pulses which correspond 
to emphasize contours. 
v. Since the contour information is derived from average 
terrain-slope information, the contours are straight-line segments of 
constant spacing within each printing scan pattern area. Also, the 
width of the line varies as a function of terrain slope, increasing 
in width with decreasing slope, according to the fractional value of 
elevation change represented by the sensitivity of the comparison 
circuits. The sensitivity band of the comparators can be adjusted 
to vary the relative contour line width from 5 to 50 percent of the 
contour interval. 
w. The AS-11B/C system also provides magnetic-tape recording 
of the XYZ model coordinates during compilation of either the coordinato- 
graph or latent-image outputs. Additional data, selected through the 
computer, may also be recorded. Recording is performed at selected 
intervals along the contour or profile line at rates of up to 25 
points per second. 
56, Equipment Components - The AS-11B/C consists of seven major 
component parts of hardware. These are: (1) Viewer, (2) Computer, 
(3) Coordinatograph, (4) Correlator Cabinet, (5) Orthophoto Controller 
Cabinet, (6) Orthophoto Printer, and (7) Magnetic Tape Recording Unit. 
  
Ihe first three components are similar in physical size and shape 
to the AS-11A. By adding the correlator cabinet and associated 
electronics, the automatic contouring and profiling capability is 
achieved (this system is referred to as the AS-11B). The addition of 
the last three components augment the system according to their 
component names (the orthophoto capability is referred to as the 
AS-11C). Figure 6 shows the AS-11B System and Figure 7 shows components 
of the AS-11C System. 
(1) Viewer - The AS-11 Viewer is a precision stereocomparator 
wherein each photograph is servo-controlled by the computer to maintain 
the correct photo point aligned with the viewing and scanning axis. 
This operation is accurate to within five microns. The viewer contains 
high-resolution binocular viewing optics with variable image rotation 
and magnification for each eyepiece. The optics are controlled by 
the computer to maintain stereo viewing throughout a convergent or 
panoramic model, The viewing unit also contains operator controls for 
data entry and display and for performing manual operations. These 
include control switches which select computer-stored quantities for 
display and/or modification, X and Y handwheels, and elevation-control 
footwheel. 
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