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CONCLUSION AND OUTLOOK
| Although the results can not be pre-
sented in its entirety in this paper it
could be shown that with a relatively
small effort the reconstruction of a sur-
face of a natural stone with an high ac-
curacy can be realised. Because the ac-
count of the weathering process is not a
priori known, an approach passing into
macro-photogrammetry as described in
/Mauelshagen, Strackenbrock 1990/ would
have been more suitable. The resolution
which can be achieved in that way - in
the range of some microns - is in better
accordance with the structure of a natu-
ral stone.
Regarding the developments in the
area of digital photogrammetry relying on
surface reconstruction for a close-range
application like this one new perspecti-
yes are given. Taking digitized photos or
using a CCD-camera it is also possible to
meet the task. At our institute a first
attempt will be made. Then the surface
reconstruction will be evaluated with Fa-
cet Stereo Vision (FAST Vision), an ap-
proach introduced by Prof. Wrobel /Wrobel
1987/. In the future more and more auto-
mazation of the measuring process will be
achieved. This offers the curators of mo-
numents a photogrammetric tool which en-
ables a quick interfering if stones are
threatened by weathering of stones.
ACKNOWOLEGDEMENTS
The author sincerly thanks:
Mr. Niebel for his support at the outdoor
work and the modification of the cameras,
Dr. Stephani from the Chair of Photogram-
metry and Remote Sensing (TU Munich, FRG)
for making the testfield available to us
and for his support at the calibration.
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