CIPA 2003 XIX th International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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0 2 2 3 5 n 
Figure 9. Digital photo of Tower 5 at Ankara Kale before 
and after rectification. A rectified greyscale image is inserted 
to the AutoCAD file to match the control points and an 
outline drawing of the individual stones can be produced by 
digitisation. The image can also be printed to scale and stone 
outlines traced by hand, preferably on acetate. 
The final example chosen to illustrate rectification and 3D 
modelling techniques is a study of the Byzantine-Ottoman 
castle walls of Ankara. The research is undertaken by Sinan 
Suluner as part of his PhD thesis, supervised by Prof. Dr. 
Omur Bakirer. The study focused on the towers at the Ankara 
Kalesi Zindankapi where recent restoration work has been 
carried out under the auspices of the Turkish Ministry of 
Culture. The aim was to produce a 3D model of the towers 
and rectified photographs of wall faces from which scaled 
elevations could be drawn. The graphics and drawings assist 
in the analysis and the statistical study of the building 
materials that were used and reused during construction in 
the Byzantine and later periods. 
To collect the necessary data, a GPS survey was conducted 
over seven days using a Trimble 4600 LS rented from the 
British Institute of Archaeology at Ankara. T his GPS system 
utilises a base station and a roving antenna to provide highly 
accurate measurements. Approximately 10,500 readings were 
taken. A static survey, lasting two days, provided the UTM 
WGS 84 coordinates for a selection of fixed points located 
during the restoration work. Data processing was done with 
the GPSurvey program. Points needed for the rectification 
were also collected using the static survey technique while a 
kinematic survey provided data for a 3D surface model 
constructed using the G1S software Arcview 3.2 and Arcview 
8.2. 
Where it was not possible to measure points with the GPS, 
either because of the inaccessibility of the point or because 
the GPS signals were masked, a theodolite was used. Kemal 
Giilcen, from the METU Photogrammetry Laboratory, 
carried out the theodolite survey, measuring (x,y,z,) 
coordinates for all necessary points. AERIAL 5 was used to 
rectify the digital photographs (Fig. 9) from which tracings of 
individual stones were done. 
3. CONCLUSIONS 
There are, perhaps, three largely separate but overlapping 
areas in which these techniques can be used and developed: 
1. Rapid, efficient, accurate and detailed recording, 
or documentation, of archaeological and architectural 
features. Applications include the recording of standing 
structures, such as built defences, and of excavated 
remains. It is possible, and indeed desirable, to use these 
techniques in emergency situations as well as in routine, 
day-to-day, recording. 
2. The 3D models permit realistic rendering and 
multi-perspective views of monuments in their present 
condition and situation. Modelling will also allow 
projection of the effects of active restoration and 
conservation schemes. 
3. The graphic displays of heritage sites and 
monuments, as they are at the moment and as they may 
once have been, permits world-wide dissemination to a 
variety of audiences. This can be achieved by means of 
the World Wide Web, publication on CD-Rom or DVD, 
or in printed form. 
The methods and techniques used for the different studies 
were selected so as to provide a comparative study of 
different approaches. The potential of Information 
Technology and GIS tools in the study of architectural and 
urban elements of the historical and the present environment 
has been demonstrated. They could equally well be used to 
make visual projections of the results of active and intrusive 
conservation and restoration programs. It must however be 
noted that the increasingly sophisticated software and 
hardware are continually stretching both human and financial 
resources, and the need to upgrade the hardware or to acquire 
new software is difficult to meet. 
4. REFERENCES 
Baturayoglu, N., Summers G.D., Summers, F., Aydin, N., 
2001. The Survey and Documentation of an Iron Age City in 
Central Anatolia: Kerkenes Dag, Proceedings 18 th 
International Symposium CIPA 2001, 18-21 September 
2001, Potsdam (Germany), pp. 407-414. 
Baturayoglu, N., 2001. The Survey and Documentation of 
the City Wall and Cappadocia Gate of the Iron Age 
Settlement on Kerkenes Dag in Central Anatolia, 
Proceedings 18 th International Symposium CIPA 2001, 18-21 
September 2001, Potsdam (Germany), pp. 100-107. 
For further information on the Kerkenes Project, see: 
http://www.metu.edu.tr/home/wwwkerk/index.html 
5. ACKNOWLEDGEMENTS 
Studies reported here have been conducted by METU staff 
and students involved in research undertaken from the 
Kerkenes Project Office, Faculty of Architecture. We thank 
all those who have been involved in this multi disciplinary 
research as well as those who provided technical or financial 
support, in particular ESRI, ERDAS, Islem GIS and John 
Haigh (AERIAL). METU Faculty of Architecture AFP grants 
(1999 to 2001), coordinated by Prof. Dr. Omur Bakirer, have 
largely supported the ongoing studies. We also thank Refik 
Toksoz and Geoffrey Summers for sharing their expertise.