Dorffner, Lionel
HAGIA SOPHIA - PHOTOGRAMMETRIC RECORD OF A WORLD CULTURAL HERITAGE
Lionel DORFFNER *, Karl KRAUS *, Josef TSCHANNERL *
Orhan ALTAN **, Sitki KULUR **, Gónül TOZ **
* Institute of Photogrammetry and Remote Sensing, Vienna University of Technology, Austria
ld@ipf.tuwien.ac.at, kk@ipf.tuwien.ac.at, jt@ipf.tuwien.ac.at
*** [stanbul Technical University, Divison of Photogrammetry, Turkey
oaltan@srv.ins.itu.edu.tr, skulur@srv.ins.itu.edu.tr, gtoz@srv.ins.itu.edu.tr
Working Group V/5
KEY WORDS: Hagia Sophia, cultural heritage, documentation, surface reconstruction, true orthophoto, virtual reality
ABSTRACT
The Haghia Sophia in Istanbul belongs with its unique dome construction to the outstanding and extraordinary
architectural structures in the whole world. Built between 532 and 537 during the Byzantine Emperor Justinian (527-
565), it reflects the sum of all experiences and knowledge of the classical antiquity and it is one of the important
monuments of the world heritage. Nowadays the building is under investigation sponsored by UNESCO. New
techniques of digital applications in photogrammetry and information sciences open new possibilities for documentation
and investigations of such kind of buildings. The Conservation and Restoration Branch of Historical Buildings asked
the Photogrammetry Division of the Istanbul Technical University to prepare orthophotos of the Hagia Sophia.
Together with the Institute of Photogrammetry and Remote Sensing of the Vienna University of Technology, it was
decided also to create a high quality 3D model of the dome, so that the obtained results can later be also used in an
“Hagia-Sophia Information System”. This information system has to collect all information about the building and will
be a useful guide for everyone. As one result a 3D photo-model was generated and stored using the data format VRML
(Virtual Reality Modeling Language). This paper describes the measurement process, the generation of the 3D model,
the production of the terrestrial orthophotos and the setup of an information system.
1 INTRODUCTION
The capital of the Ottoman Empire, Constantinople, was located on two continents. Therefore the artistic style that
developed under the Ottomans shows elements of the eastern and western heritage. The Hagia Sophia in Istanbul is one
of the most influential buildings of Byzantine architecture and belongs with its unique dome construction to the
outstanding and extraordinary architectural structures in the whole world. It reflects the sum of all experiences and
knowledge of the classical antiquity and it has been accepted as one of the important parts of the world heritage. Hagia
Sophia was since years the focus of all searchers and historians from all over the world. The dome itself, with a span-
length of almost 30meters, lies beyond the Roman Pantheon (43m) or Petersdom (42m). But it exceeds them with its
space composition in a certain way, that, when entering the building, the structural masses and the load carrying parts
are not visible at the first view.
Starting from the proposal of the Conservation and Restoration Branch of Historical Buildings in Istanbul of the
Ministry of Culture to prepare orthophotos of the Hagia Sophia before the long time standing scaffold inside the
building is removed to another place, the Photogrammetry Division decided in accordance with the Conservation and
Restoration Branch to apply the most recent technologies together with the Institute of Photogrammetry and Remote
Sensing of the Vienna University of Technology and to create a so called 3D photo-model [Kraus K., 1997] of the
dome, so that the obtained results can later be also used in an “Hagia-Sophia Information System” which will be a
very useful tool for documentation. The 3D photo-model is stored using the data format VRML (Virtual Reality
Modeling Language). This format was chosen because it enables on the one hand a user-friendly interactive
visualization and examination of the data and on the other hand provides a lot of possibilities to link additional
information (texts, sounds, movies...) to the 3D model. Besides, most of VRML viewers are available free, so that no
additional costs arise for the viewing software.
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000.
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