of the trajectory. The precision 3-axis mount allows for
rotations in azimuth, elevation, and roll. Interchangeable
lenses of 5, 7, and 10 inch, nominal focal lengths are fitted to
the cameras. Film measurements are made to 3 fiducial crosses
which are internally projected onto the film, and which define
the film coordinate system. Timing data are indicated along one
edge of the film by a 1000 cycle per second flashing bulb. Full
second time is indicated in binary code.
In normal operational use, orientation of the CZR-1 camera
may be performed by using target boards, dials, or a combination
of the two methods. Triangulation is performed using 2 through
} camera combinations with the best geometry obtainable under
ordinary field conditions. Systematic errors for this system
are normally considered to be 20 to 40 seconds of arc using
. target board orientations, and 180 to 240 seconds of are using
dial orientations. In actual operation the errors of the sys-
tem are practically doubled. On the other hand, the system has
an ultimate accuracy capability of 10 seconds of arc or better.
This value was established in an earlier test using star orien-
tations and reconstruction of the directions of rays to the
stars.
Why this tremendous discrepancy factor of 50 between the
theoretical capability, and the actual operation of the instru-
ment? This becomes the story of the systematic errors in the
system, and as stated earlier, the major source of systematic