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As the four setting screws are situated at those places, where the
height control points are most likely to be chosen, namely in the
corners of the useful stereomodel, their operation should converge
at a fast rate.
3.3 Compilation of contours
The Z-settings for the various contours can be obtained by the
formula
Zk 35 mm Hq.Sz k. A H,SZ (3)
where A H contour interval.
A table of Zj-values for all contours to be plotted should prefer
ably be prepared before compilation.
Fig. 3. Photograph of prototype.
Summary
A description is given of a simple contour plotter, which facilitates the
direct compilation of contours or form lines on paper prints, if a number
of height control points is given.
The plotter consists basically of a mirror stereoscope. However, making
use of the Deville principle, the simultaneous stereoscope observation of a
surface, consisting of vertical strings, becomes possible. The surface which
can be deformed to compensate for model deformation, virtually intersects
the stereoscopic model along horizontal planes. A prototype of this plotter
has been constructed at the ITC,
