Selected instruments and techniques 
Super wide angle camera 
Description: Aerial Camera with angular field of 1209, format 9" x 9", 
focal length 3-1/2". 
Photointerpretation application: For taking small scale color or 
black-and-white photographs from relatively low altitudes. Increased 
angular field (1200) increases vertical exaggeration with normal 
stereoscopic overlap (60%). Advantageous for geologic study or terrain 
analyses of some areas. 
Remarks : Ae ARI commercially. (Wild Heerbrugg, written communication, 
1959. 
New plotting instruments 
(Suitable for use with color and super wide angle photography) 
Description: Mechanical projection-type instruments, designated B-8 and B-9, 
that are relatively inexpensive, and will accommodate photographs taken 
with 3-1/2-inch focal length cameras. The B-8 Plotter will accommodate 
full size color transparencies. 
Photointerpretation application: Any interpretation problem whose solution 
would be facilitated by use of a third order instrument for plotting 
and measuring. Particularly suitable for problems involving super wide 
angle photography or color photography. 
Remarks: Available commercially. (K. E. Raymolds, written communication, 
1959.) 
Stereoscope for viewing uncut film 
Description: Stereoscope (fig. 2) designed for viewing on x 9" or 9" x 18" 
uncut aerial photograph transparencies. Modifications of this 
instrument are available for viewing 4-1/2" x 4-1/2" film. One version 
of this instrument has 3x magnification, another has powers of 2-1/2x, 
6x, and 12x. 
Photointerpretation application: Any photointerpretation problem wherein 
storage, use, or time of interpretation would be facilitated or 
shortened by maintaining transparencies in roll form. 
Remarks: Available commercially. (R. T. Shone, written communication, 1959. ) 
Stereoscope mount for double viewing 
Description: A wooden mount (fig. 3) to raise two mirror stereoscopes and 
fix them in an oblique position. 
Photointerpretation application: To make it possible for two interpreters to 
view the same pair of photographs simultaneously without special 
equipment. (Professor Carlos Eugenio Magarinos Torres, written 
communication, 1959.)