432
n — 1 degrees of freedom, where n is the number of photographs in
the strip have been used for the practical and theoretic values. The
following ratios have been found:
The strip 6010a 0 1.88 Q /. 1.46
6010b 0 1.43 Q 1.08
6011 0 1.22 Q 1.44
The table values for F 2 .5 are 2.31, 2.68 and 4.03 in the respective
strips. Consequently it may be assumed that practical and theoretic
values are similar, proving that two determinations of the inclination
angles from differeni image halves do not give significant correlations
provided that the assumptions for the theoretic derivations with respect
to the interior orientation of the main camera have been right.
7. The precision of the horizon camera values.
2—3 reference pictures have been used in measuring the horizon
pictures. Thus there are many determinations of the inclination angles.
The precision of the inclination angles has been computed by means
of these values and the following result has been obtained:
s
S M
s
S M
Strip 6010a
0
2.1 I e
1.22 c
Q
2.07 c
1.20 e
6010b
0
1.39 c
0.98 c
Q
1.26 e
0.89 e
6011
0
1.26 c
0.89 c
Q
2.87 e
2.03 e
Root mean
square value
0
1.74 c
o
GO
rs
Q
2.03 e
1.32 e
where s — the standard deviation of one measurement
and s M = „ ,, „ „ the arithmetic mean
According to the formula (2) it is possible to calculate the precision
of the image coordinates in the horizon pictures backwards. After
inserting the standard deviations into the quantities /3, R and h the
following result is obtained:
Si = —75= V /s 7 + s 3 2 (25)
f V 6 >
where Sj_= the standard deviation of one measurement
$2 }> >> >> >> >> >>
s 3 >> ” >> >> >> >>
P = 6366.2 c
(0.01 g ) in p
(mm) in R
(mm) in h