lens distortion and
CCD
geometric deformation mainly affect
the height positioning accuracy of the
GFXJ
camera.
The experimental results for Data C are plotted in Figures
17–20. Figure 17 shows the residual error distribution for 85
control points after
DG
. Figure 18 shows the residual error dis-
tribution after
AT
& Calibration. Figure 19 shows the residual
distribution of the direct positioning using
CAM
files. Figure 20
shows the residual distribution of the direct positioning using
both updated
GNSS
/
IMU
observations and
CAM
files. From the
analysis of Figures 17–20, similar conclusions can be drawn.
The
AT
& Calibration process can effectively eliminate the
systematic errors of the
GFXJ
camera and improve the position-
ing accuracy. Lens distortion,
CCD
rotation, scaling and other
Figure 17. Geometric residual distribution for Data C after
DG
.
Figure 18. Geometric residual distribution for Data C after
AT
& Calibration.
Figure 19. Geometric residual distribution for Data C after
the second
DG
.
Figure 20. Geometric residual distribution for Data C after
the third
DG
.
Figure 13. Residual distribution for Data B after
DG
.
Figure 14. Residual distribution for Data B after
AT
&
Calibration.
Figure 15. Residual distribution for Data B after
DG
Using
CAM
Files.
Figure 16. Residual distribution for Data B after
DG
using
updated
GNSS/IMU
observations and
CAM
files.
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
September 2019
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