Ebrahjm, Mostafa Abdel-Bary
Photogrammetrist very often estimate the accuracy of a method by controlled experiments, where the
photogrammetrically determined co-ordinates are compared with so called given co-ordinates that have an accuracy that
considerably higher than that of the method to be checked (Ebrahim, 1992).
2. THE TEST FIELD
2.1 Its Natural
A part of the ceiling of Abdel-Raheem El-Kenawi’s mosque has
been chosen as a test field for this investigation. Its flat ceiling and
its domes has a very beautiful decoration which has been painted
by the Islamic artists. The test field consists of one panel of the
whole ceiling which contains a dome centered in its flat ceiling.
The diameter of the dome is about five meter and the dimension of
the flat ceiling is about 8 x 8 meters. It surrounded by a system of
regular columns which carry a sold part decorated with a beautiful
painting and calligraphy. Above the sold part, there are a row of
windows covered with regular Islamic pattern . Theses windows
separates by painted posts which carry the flat ceiling and the
dome. Figure (1) shows part of the panel.
2.2 Its History Figure (1) Part of the panel
The mosque was built in 1948 by the constructor Aal-Zarea from Gerga city. An extension for the mosque has been
done in 1989. This extension is a copy of the main part of the mosque. Beside the main part, lies the shrine of Abdel-
Raheem El-Keenawi which directly connected to the main part.
2.3 Its Location
The mosque lies in the main square of Kena city which far from Cairo by 518 Km to south. The main entrance is in the
western side and the shrine of Abdel-Raheem El-Kenawi lies in the eastern side. The test field panel lies in the southern
side of the mosque.
3. THE USED CAMERA
A non-metric camera, YASHICA Zoomtec 90 Super, has been used in this investigation. The focal length of the
camera has been fixed to 38 mm. A self calibration for the camera has been done by the used photogrammetric software
through the processing of the project. As this camera is a non-metric camera, a separated camera has been defined for
each photo in the used software. Roll film (FUJI 100 ASA) was used with this camera with 24 by 36 image format. The
photos have been scanned via a flatbed scanner *MUSTEK ScanExpress 600 SEP".
4. THE EXPERIMENTAL WORK
4.1 The Study Procedure
1. Gather up data about the test field
2. Take ten photos of the test field with the used camera.
3. Scan the photos by a flatbed scanner.
4. Set up the camera in the used photogrammetric software.
5. Mark all the points on all images.
6. Process with the photos.
7. Compare results in analytical and geometrical forms.
4.2 Number Of Photos And Their Positions
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 197
