50 +83 + 4 86 
  
Qo, i chus Pee 4 p (192) 
h^ h? 
= — 4 —— 9: 
Quo; +1 bèd? + 4 d? ( 1 9 3) 
2 d? 1 
Quins = 73m 60 (194) 
If more points are used for the relative orientation the corresponding 
weight- and correlation numbers must be used instead of (174)—(182). 
2.2. The error accumulation in a cantilever extension 
The error accumulation due to the errors in the transfer points is of 
the same type as demonstrated above for the stereo-radial triangulation. 
The expressions (117) and (118) consequently can be applied also to 
the model triangulation if only two transfer points are used between 
adjacent models. 
The error accumulation is demonstrated for the center points by the 
expressions (117) and (118). The errors in arbitrary points can be found 
after adding the corresponding weight numbers. Such numbers, how- 
ever, are so small in comparison with the weight numbers of the center 
points that they can be neglected already after a few models. The 
weight number of the model coordinate measurements in the center 
points and in other points can be taken into account in adding 1 to the 
expressions (117) and (118). 
  
Hence we find 
] 
Qx,x, — 14 á (2 n 4- 1) (n 4- 1) n Q, 3- n Q,,, + (A + 1) n Q,,, (195) 
p? 
Qv, r, = 1+ 6 (2n +1) (n 3- 1)nQ,, T n Q,, 7-0 (n - 1)nQ,,, (196) 
Next the weight- and correlation numbers (183)— (188) can be substi- 
tuted into (195)—(196). For the usual six orientation points of the 
relative orientation the weight- and correlation numbers (189)— (194) 
shall be used. In order to simplify the calculations we assume wide 
angle photographs and normal overlap to be used. This means b = d 
3h