4.3 .Fig..1 shows. that auxiliary data of poor precision, as 
they will easily be available, are already most effective. 
In our example of 1:60 000 photo scale positioning data for 
camera stations with standard errors of 10 m (and attitude 
data with standard errors of 70 mgon, 1 mgon = 1,6-10-$) 
give hlock. accuracies of 1,9 min x'and y agd 3,00 in°z. ‘In more 
general terms the block accuracies are Uxy /50 = 2,1 - and 
Hz/00 = 3,3. With regard to the vertical Accuracy it is more 
general to introduce a standard vertical precision of oogz - 
09/2/0 (© = base height ratio). Then we obtain uz/097 = 1,4. 
These results refer to the weights of auxiliary data of 
Pxo.yo,zo 7 2»25-10712and p, , &: - 182-10* um*. If compared to 
standard aerial trianguls on without auxiliary data it is 
evident, that the same results could only be obtained with 
quite dense ground control. 
With increasing precision of the navigation data the resul- 
ting block accuracies improve almost linearly, reaching the 
oo and Sog level for ux,y and uz with standard errors of the 
auxiliary data of about > m (15 mgon) or weight ratios of 
5.1071? (4.10?um*). Thus, with still moderate precision of 
the auxiliary data, results are obteined which would conven- 
tionally require very dense ground control. If, eventually, 
the standard errors of the orientation data will be < 0,5m 
(and < 1 mgon) the results will be truly in the high precision 
range of aerial triangulation, opening most interesting app- 
lications for large scale mapping, too. 
The simulation results show clearly that auxiliary position 
data have the major effect on improving aerial triangulation. 
Additional attitude data change the results very little. 
Attitude data alone give very much poorer results than posi- 
tion data. The conclusion is, therefore, that navigation 
systems which give position data are of prime interest for 
aerial triangulation. 2 chains of vertical control are re- 
quired in this case, in order to avoid near-singularity. 
The situation changes completely, however, if the precision 
of attitude data is in the order of about 5 mgon (310-*) or 
better. In that case these data stabilize sufficiently the 
angular orientation of photographs. The results are then 
simular to those obtained with high precision position data 
(1 m or better) and can ensure by themselves high precision 
aerial triangulation, independent of photo scale. 
Remark: The curve showing ux,y for attitude data seems to 
represent a different type of relationship than the other 
[m] curves in fig. 1. However, these curves too would deviate 
from the apparent linearity. If further extended to the 
[mgon] right they also would approach asymptotically an upper 
4 limit, as auxiliary data of very low precision have no ef- 
E fect on the block adjustment. 
ed 
Myon 
- 11 -