P 
s ! 
P 
2 
P P, 
a) py = Co-ordinate differences between P; and P; 
" [8] 
P 
P 
2 
Oo 
p P 
t 3 
b) v4 — Co-ordinate differences between Py and Pj 
>> P 
lime TS à 
2 
P 
t 9p 
3 
c) Aq = Co-ordinate differences between P; und Py 
Ficure 1 
Clarifications regarding the r.m.s. errors (estimated values) 
according to the computing programme 
a) absolute accuracy with reference to item 3 of the computing programme ( A) 
b) relative accuracy with reference to item 4 of the computing programme (R) 
c) systematic error with reference to item 8 of the computing programme (S) 
Explanations: 
P, terrestrially determined point 
Pi, Po, P3 photogrammetrically determined point with repeated fitting of the models (i = 3) 
Py centre of gravity of P1, P» and Ps. 
15