plane is sometimes only coincidental; and is a direct funetion 
of the design and manufacture of the instrument itself. Among 
the many problems to be considered are: mislevel of the instru- 
ment, misperpendicularity of the axes of rotation, standards 
errors, collimation errors, dial graduation and eccentricity 
errors, and so forth, to name only a few. 
THE CZR-1 FIXED CAMERA SYSTEM 
The CZR-1 Fixed Camera is a modification of the RC-2, Bowen 
ribbon-frame camera developed by Dr. Ira S. Bowen at the Cali- 
fornia Institute of Technology. The camera utilizes 5% inch wide 
roll film passing over a cylindrical drum focal plane. The 
shutter is an open slit in a second cylindrical drum rotating 
around the film drum and having a focal plane shutter effect on 
the surface of the film. Both the film drum and the shutter 
drum rotates at a constant, although different rate. By varying 
the number and location of the shutter slits, a varied rate of 
30, 60, 90 or 180 frames per second can be obtained. The height 
of each frame decreases with increased frame rate; the dimensions 
being 0.90, 0.45, 0.30, and 0.15 inches respectively for the 
above frame rates. 
The camera is operated in a position of fixed orientation 
Selected to obtain maximum eoverage over the desired portion of