T TT
The following t&bulation shows the situation interpreted in terms of the re-
cording of the various points (Nos. 1-9) by the various camera stations (Nos.
T, II end III)
Point Type of Point Camera Stations at which the point was recorded
Nos. | T II IIT
i A: > x
2 O - x
3 © x x
4 O - x x
2 O x -
6 O x
T A - x
8 © x x -
9 A - X -
Counting the cross marks, we see that 19 individual rays are present, Each
ray leading to 2 equations, we have, 19 x 2 = 38 observation equations for the
55 unknowns which (assuming for example, the three elements of interior orien-
tation of each camera orientation as known) are composed of 3 x 6 = 18 elements
of orientation and (9 x 3) = 12 = 15 coordinates of the model. As an inter-
esting by-product, it may be mentioned, that the evaluation of the chosen
problem, although slightly overdetermined, would not be possible with con-
ventional restitution equipment and techniques, because there are only a
maximum of 4 intersections between corresponding rays of any one pair of photo-
graphs, as can be seen from the above tabulation.
. With the help of this tabulation we form the corresponding 38 observations
&l equations which are shown schematically in Fig. 6, In Fig. 6 each line
represents an observational equation formed according to formulas (18) with the
terms given in formulas (15), (40) and (41), The individual A matrices and
similarly the corresponding P -matrices actually &re & sequence of completely
separated sub-matrices. An inspection of Fig. 6 shows the fact, which has
already been mentioned, that in case there are no V's, the À matrices become
& sequence of unit matrices.
46
No. of observation equations
+
OW aN OPN =