International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B4. Istanbul 2004
Table 4. Standard deviations of the adjusted ground coordinate
of MOLA and tie points
Site Type | ox(m) | oy(m) | oz (m) Zo
(pixel)
Eos MOLA | 9.210 8.941 10.183 1.037
Chasma Tie 99.012 | 141.643 | 43.296 ps
Gusev | MOLA | 7.869 10.205 . | 10.158 1.059
Crater Tie 21.270 | 5.020 6.633 t
Isidis MOLA | 18.297 9.799 18.302 1.014
Planitia Tic 7.344 | 57.934 | 8.684 :
5.3 MOLA and MOC Registration
The image coordinates of MOLA ground points are calculated
using adjusted exterior orientation coefficients after the bundle
adjustment. The new image coordinates can be compared with
the mis-registered image coordinates of MOLA profiles
obtained before bundle adjustment to examine the improvement
as a result of the bundle adjustment.
The improvement of the MOLA registration can be examined
by visual checks in Figure 2 and Figure 3. Figure 2 shows the
comparison of the MOLA profile registration on stereo images
before and after the bundle adjustment in Gusev Crater site.
The results of all sites show considerable improvement of
MOLA registration. However, only Gusev Crater (Figure 2)
and Isidis Planitia (Figure 3) results are provided due to the
limit of space. Figure 2 (a) images are the MOLA profile
registration overlaid with MOC stereo pair images before
bundle adjustment. The MOLA profiles show the systematic
registration shifts around one MOLA GSD, about 325 meters,
in both stereo pair images. The index number 77 of MOLA
profile is projected outside of a crater in the left stereo pair
image and, inside of the crater in the right stereo pair image in
Figure 2 (a) Figure 2 (b) images are the MOLA profile
registration after the bundle adjustment with the contribution of
tie points, MOLA ranges and other measurements. Figure 2 (b)
is the MOLA registration after the bundle adjustment using new
adjusted exterior orientation. The MOLA profile with index
number 77 is projected to the same positions slightly outside of
the crater on the both stereo pair images. Figure 3 shows
MOLA registration to MOC stereo images in Isidis Planitia.
Figure 3 shows the MOLA registration results before (Figure 3
(a)) and after (Figure 3 (b)) bundle adjustment in Isidis Planitia.
Figure 3 also shows MOLA profile with index numbers near a
crater in Isidis Planitia site to easily identify the MOLA
registration results. MOLA profile locations from index 6 to
index 8 are different in the stereo pair around the crater area in
Figure 3 (a). However, they are correctly projected to the same
in Figure 3 (b).
Figure 4 is the bundle adjustment results with MOLA profiles
and tie points overlaid with MOC stereo pairs. Figure 4 (a)
shows the stereo pair of Gusev Crater site and Figure 4 (b) is
the stereo pair of Eos Chasma sate. MOLA profiles show linear
pattern on the images, while tie points are scattered over the
images. Because the tie points are not changed after the bundle
adjustment, it shows exactly the same location as they are
collected either manually or automatically. In Figure 4, image
coordinates of MOLA and tie points are projected to the same
position of both stereo pair images.
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Figure 2 (a). MOLA registration before bundle adjustment in
Gusev Crater
Figure 2 (b). MOLA registration after bundle adjustment in
Gusev Crater
Figure 3 (a). MOLA registration before bundle adjustment in
Isidis Planitia
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