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Technical specifications of photoshutter 
CA-M 
The range of effective 
time of exposures - 1/35 to 1/200 s 
Shutter efficiency — not less than 0.6 
Asynchronism of photo- 
shutter operation in the 
channels - 2 — 4 ms. 
The operational information imprinted on the 
mterframe intervals and on the frame field contains 
the data necessary for ground processing of survey 
materials. 
The composition of ope 
at iona1 
informat ion: 
Frame number; 
Value of real exposure; 
Code of on—board uniform time; 
Picture of the clock with the central second hand ; 
Picture of photometric wedge; 
Film numbe r; 
Equipment designation; 
Photogrammetric focal distance of channel; 
Launch date of satellite; 
Number of levelling glass; 
Zone number; 
Fiducial marks along the field frame. 
The cassete unit of CA—N photocamera can load 
600 m. film of 90 mcm thick to each channel, which 
corresponds to 2500 frames. So depending on the 
selected altitude of orbit the survey of the Earth 
surface is done with the area of 11.5 to 58.3 sq.km 
with 60% forward overlap and with 20% of side overlap 
between neighbouring images and strips respectively.