TABLE 1. SPECIFICATIONS OF GSI CLOSE-RANGE CAMERA CRC-1 
  
  
GENERAL 
eLarge format (23 x 23 cm) roll film camera 
«Standard aerial mapping film reels used (9.5 inch width, 4 inch diameter) 
Capacity approximately 140 exposures per roll (125 feet, 4 mil thick) 
Four illuminated corner fiducials 
FILM PLATEN 
Film flattened by means of internal vacuum pump 
Patented reseau system incorporated into back of platen 
(7 x 7 array standard; 13 x 13 array optional) 
Surface flat to within #5pym; function defining departures 
from flatness calibrated to within £0.50ym. 
*Platen rigidly fixed with respect to lens cone, rendering each 
reseau image the equivalent of a fiducial mark. 
INTERCHANGEABLE LENS CONES 
120 mm (88° x 88°) 
«155 mm (73° x 739) 
«240 mm (51° x 51°) 
«360 mm (35° x 35°) 
«450 mm (28° x 28°) 
FOCUSSING 
*Continuous focussing by micrometric drum graduated in units of lOym. 
*Focussing range: 1.2 m — o, 120 mm | 
1.6 m — o, 155 mm 
2.5 m — o, 240 mm 
4.0m — o, 360 mm 
5.0 m — o, 480 mm 
LENS CALIBRATION 
«Stellar calibration of elements of interior orientation and coefficients 
of radial and decentering provided for each lens cone for infinity focus. 
Plumb line calibration of coefficients of radial and decentering distortion 
provided for each lens cone for near field focussing limit. 
FILM TRANSPORT 
Digitally controlled drive motor mounted in film magazine 
Two second cycling 
Incremental advance mode in 1.0 mm steps permits execution of 
multiple exposures on same frame when retroreflective targets used. 
MISCELLANEOUS 
Precise roll ring permits rotation about camera areas through +180° 
(position of center of projection unaffected by rotation) 
«Shutter controlled by cable release, speeds 1 to 1/125 second and bulb 
eAuxiliary 35 mm SLR camera serves as viewfinder 
Power, 12 V DC external gel cel battery 
Weight, approx. 22 kg 
  
  
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