ISPRS Commission III, Vol.34, Part 3A ,,Photogrammetric Computer Vision“, Graz, 2002
.
Figure 7. Project Svinesund, six strips. Left: strips. Right:
elevation
In this case the crossing strip helped to discover a deformation
of the strip. It is not clear what has caused the deformation but
the guess is a scale factor error in the mirror roll angle. The
same kind of deformation was found by (Crombaghs et al.
2000). This deformation was not modelled or compensated for.
The final corrections for the project Svinesund are presented in
table 5.
Flightlin | Points | Z shift | Hshift | Rshift | P shift
e [m] [rad] [rad] [rad
1 778 -0.010 | -0.0005 | -0.0001 | +0.0001
5 626 +0.027 | -0.0004 | -0.0001 | -0.0000
2 1188 | -0.028 | -0.0008 | -0.0003 | +0.0001
4 1070 | -0.001 | -0.0000 | -0.0001 | 40.0000
3 1180 | -0.023 | -0.0003 | -0.0001 | 40.0002
6 777 +0.009 | -0.0001 | -0.0000 | +0.0003
Table 5. List of final corrections in the Svinesund project.
3.5 Project Gävle
Fotonor flew this mission for the National Land Survey of
Sweden. The main purpose was to investigate the possibilities
of using laser scanning to update the National Height Data
Base in Sweden. Therefore, the flying altitude was rather high
(about 1700 m). They wanted cover different land use
categories, which lead to a rather elongated flight with five
different strips (figure 8). The area was rather flat (figure 9)
and most of it was covered by forest.
Figure 8. Strips in the Gävle project
Figure 9. Elevation in the Gävle project
The final corrections are listed in table 6.
Flightline | Points | Z shift | R shift
[m] [deg]
5 816 | -0.120 | -0.0192
4 1784 | -0.029 | -0.0004
3 2212 | +0.015 | +0.0099
2 2033 | -0.178 | -0.0026
1 3278 | +0.137 | +0.0017
Table 6. List of final corrections in the Gävle project.
In this case there was an elevation offset between the two
strips in the north. This can be illustrated by thinning the
ground points where there is a small change in gradient, i.e.
