In order to reduce the statistical uncertainty of the
accuracy results, all simulations were performed several
times. The number of required repetitions depends on
the geometrical stability of the blocks. Blocks with all
navigation data are more stable than without or with
attitude data only. The obtained relative precision of
the final values Br» By,» b, can be indicated as follows:
- simulations with block size Bl (10 x 41 photographs)
without navigation data: 7 - 10 %
- simulations with block size Bl (10 x 41 photographs)
with nativation data: 2 -.10 $
- simulations with block size B2 (5 x 21 photographs)
without navigation data: 1 - 10 $
- simulations with block size B2 (5 x 21 photographs)
with navigation data: L - 5 $.
Remark: The photogrammetric measurements of the (X,Y, 2)
control points are treated as error free, in order to
separate the block accuracy from the effects of datum
transfer.
3 Results
The results of the various simulations are summarized in
tables.2-.4 and in figures 2 - 8... The. direct accuracy
results are connected to relative terms (n, /]9,555 M, 7/9, ,
x 0 y. 0
p, f 06 and à {9 where py, is the rms value of B. and y.)
in order to make them transferable to other cases. The
acutally chosen weight unit 0, * [d5.v um sis of: no
particular meaning except for the weight ratios
involved.
The results will be compared and discussed with
reference to several considerations.
3.1 All exterior orentation elements, no ground control
If all 6 camera orientation parameters are observed the
blocks are determined and stable without any ground
control (with regard to the navigation reference
system). This Case (CO) shows the effects of auxiliary
data and of their accuracy in its purest form.
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