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29)
305
(model) consists of. 30 points with six
control points has been done. The interior
and exterior orientation parameters for
both left and right photos were assumed.
the geometrical dimensions were the base
length (P). = 5.00 m, and the object
distance (H) - 10.00 m. Random errors were
added to each photo coordinate (0 to +
0.05 mm) to simulate the measuring errors
and random imzge deformations (e.g. lens
distortion, film deformation, ...etc.).
Table (1) shows the standard deviation for
object (check points} space coordinates
(in cm).
Stand.| Metric Non-metric
dev. case Case
um 0.1535 1.1270
c 8.1115 3.1103
em 0.3983 0.4976
cr 0.4440 1.5252
Xyz
Table (1)
A practical test was carried out by
Ebrshim (1992) using a phototheodolite
19/1318 metric camera. The control field
consisted of 50 check points, among which
8 control points were chosen. The object
distance was taken as H- 10.00 m. image
coordinates were taken for 15 stereopsirs
of photographs using Zeiss Jena
stereocomparator 1818 in the
photogrammetric Lab. in Assiut University.
The standard deviation for the object
space coordinates were determined using
the proposed method. The results were
compared with those calculated by the
collinearity method as a standard method.
Table (2) shows an example of the results
of the standard devistion for check and
control points (in cm) using both the
developed method and the collinearity
method.
Stand. Check points Controi points
dev. Rew | Collin.] — New] Collin.
e 8.057 0.059 0.00017] 0.047
e 0.061 0.071 0.00018[ 0.050
e? 10.186 | 0.193 ]0.00060| 0.232
eun 0.185 0.214 0.00085] 0.242
Tabie (2)
401
CONCLUSION
The developed method described here has
proved an increase in the accuracy of the
orientation parameters for both metric and
non-metric cameras, which affected
directiy the accuracy of the
calculated space coordinates for both
check and control points. This increase in
accuracy may be referred to the reduction
in the number of the unknowns in the
equations of the developed method when
compared to the collinearity method, (5
unknowns instead of 9 in the case of
non-metric cameras, and 5 unknowns instead
of 6 in the case of metric cameras). This
means that the number of iterations and
consequently the computing time is
reduced.
BIBLIOGRAPHY
1i- Abdel-Aziz and Karara, 1874. accuracy
aspects of non-metric imageries.
Photogrammetric Engineering. p.p.
1107-1117
2- Ebrahim, M.A., 1992. Using close-range
photogrammetry for some engineering
applications
3- Hottier, Ph., 1978. Accuracy of
close-range Analytical restitutions
Practical experiments and prediction.
Photogrammetric engineering and remote
sensing. Vol.42, No.3. p.p. 345-375
4- Torlegárd, A.K., 1981. Development of
D EE photogrammetry and its
future. 5 anniversary meeting of the
Finnish society of photogrammetry.
p.p. 49-72
5- Verdina, J., 1971. Projective geometry
and point transformation. Allyn and
Bacon, Inc.
Wolf ,P.R.,1974 .Elementsof photogrammetry
Mograw-Hill, Inc.
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