stanbul 2004
IBI xl
MilMeter(R)
le status
«inl xj
; 67 ya
et
"T
Milifeter(R)
m 4.40
iur
ec
y-axi
d directions
"TON
re has been
nagery was
aera (almost
| point. The
curacy in X,
accuracy of
1e geometric
on over the
nts, exterior
s have been
| the aero-
of terrestrial
es had to be
used, that the
ontrol points
liquity of the
at case, the
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part BS. Istanbul 2004
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)
- A Drawing of 12 facades (1:50) (Figure 9)
- 5 Profiles (1:50)
5. 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 1s 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
e
computed orthophoto
6. CONCLUSIONS
Evaluation of ancient settlements and cultural heritage has
always been one of the most interesting topics in
photogrammetry. One of the difficulties by archaeological
photogrammetry is the position of the camera. Suitable camera
position cannot be arranged in any cases. In this study, a
different platform has been used for image acquisition. The
interesting point of the image acquisition system is the
availability of the covering area in the monitor by the ground
operator. This causes more effective work on the field. Another
interesting point is the structure of the camera holder, so that it
acts likely as a compensator. This causes to take more suitable
photos for photogrammetric applications.
In archaeological sites, excavations take place mostly in
summer. This causes — especially in Mediterranean part of
Turkey- to work in hot weather. Thinking about the contrast on
the images, this was a disadvantage. Because of that, image
acquisition has been done very early in the morning. Nearby, in
those hours, it is very silent and not windy. This 1s an advantage
for using the helium-balloon too.
It is well known that oblique photos have some problem during
exterior orientation. But in some cases like facade evaluation
etc. this is a must, if any of the additional equipment has been
used. Ongoing study is to use the balloon and the camera for
façade imaging especially for tall or non-reachable building.
7, REFERENCES
Leloglu, U.M., Tunali, E.and Algun, O., Aerial Photos,
http://vega.bilten.metu.edu.tr/aerialphoto/, (accessed on 12 June
2003)
Miyamoto, M., Yoshino, K. and Kushida K. 2001.
Classification of wetland vegetation using aerial photographs
by captive balloon cameras and aero NIR color video image,
Kushiro northern wetland in Japan. In: 22 Asian Conference
on Remote Sensing, Singapore.
Karras, G.E., Mavromati, D., Madani, M., Mavrelis, G.,
Lymperopoulos, E., Kambourakis, A. and Gesafidis, S. 1999.
Digital orthophotography in archaeology with low-altitude non-
metric images. In: International Archives of Photogrammetry
and Remote Sensing, 32 (SW11), pp 8-11
Kemper, G., Celikoyan, T.M., Altan, M.O. and Toz, G. 2003,
Balloon-photogrammetry for cultural heritage, In: a
International Symposium Remote Sensing of Urban Areas, 27-
29 June 2003, Regensburg, Germany