4.12b
4.12c
4.13
4.21
4.22
-» lll.
Is it checked by plotting of & standard stereopair?
Yes 14 Not answered 2
No 4T
Is it checked by other methods?
Yes 8 Not answered 3
No 52
Are there fixed tolerances for accuracy of instruments?
Yes 52 Partly
No 7 Not answered
By how many operators are the instruments run”
l operator 26 1 or 2 operators 15
. 2 operators 20 Not answered 2
For how many hours per day are the instruments exploited?
5 hours 3 Variable 10
hours T Not answered 1
hours 13
11 hours 4
12 hours 6
13 hours 1
14 hours 8
15 hours 2
16 hours 8
17 hours 1
18 hours 2