CIP A 2003 xix"' International Symposium, 30 September - 04 October, 2003, Antalya, Turkey
some details on the photos such as stone'Comers etc. have been
used as control points (Figure 6)
Figure 5. Aerial photo taken from the balloon and a control
point zoomed in.
Figure 6. Terrestrial photo
3. PHOTOGRAMMETRIC EVALUATION
For photogrammetric evaluation, Pictran software has been
used. Exterior orientation of the aerial imagery was
unproblematic due to the position of the camera (almost
vertical) and the coordinate accuracy of control point. The
control points have been measured with 2-3 mm accuracy in X,
Y and ~4 mm. in Z direction. The geometric accuracy of
evaluation results for aerial images was about 4 cm.
Exterior orientation was fine also because of the geometric
accuracy of control points and their distribution over the
images. Using only the ground control points, exterior
orientation was already fine but some tie points have been
measured for getting better stabilization in the aero-
triangulation.
Difficulty of this study was the exterior orientation of terrestrial
images. In some parts of the study area, the images had to be
taken very closed to the object of interest. That caused, that the
single image covers a small area. Therefore many control points
on the facades had to be measured. Nearby, the obliquity of the
photos forced some additional problems. In that case, the
exterior orientation of some facades have been a big work and
needed long.
By photogrammetric evaluation, over 100.000 points have been
measured three dimensionally. This step was the biggest work
of the whole study. The measured 3-D coordinates of the stones
and their contours have been transferred in CAD-Software.
Editing and some additional cartographic works have been done
using AutoCAD.
At the end of the study, following maps with different scale
mentioned below have been created.
Layout plan (1:250)
Detailed plan (1:100) (Figure 8)
Drawing of 12 facades (1:50) (Figure 9)
5 Profiles (1:50)
4. FURTHER ACTIVITIES
The processing of the data is at least a big work, especially if
we use point-based systems. The possibilities of PhoTopoL
Software are, to be able to digitise directly lines in 3D and to
control them in stereo. This is possible for aerial images as well
as for terrestrial photographs. With some limits to resolution
and accuracy, also oblique photos can be processed. Further on,
the orthophoto production in such a system is possible, which
reduces the need to map all lines and increases the information
on the map dramatically. An example is given below. Such
tools are the key for complex 3D modelling up to the creation
of visualisations and animations. This will be tested.
In this frame, the data can be stored in GIS application as well
to be part of web-based GIS-application for tourist affairs and
as well as for archaeological reconstruction aims.
Figure 7. First results of edge mapping in PhoTopoL with
computed orthophoto
