DOCUMENTA TION OF THE SILHOUETTE CHANGES OF ISTANBUL USING DIGITAL 
PHOTOGRAMMETRIC METHODS 
S. Kulur 3 , M. O. Altan 3 , Z. Duran 3 , Y. Kardas b 
a ITU, Civil Engineering Faculty, 34469 Maslak Istanbul, Turkey - (kulur, oaltan, duranza)@itu.edu.tr 
b Erdem EMI Mapping Information Construction and Transport Industry Co. Ltd. - ykardas@emi.com.tr 
Commission IV 
KEY WORDS: Cultural Heritage. Photogrammetry, Conservation and Documentation. 
ABSTRACT 
Istanbul is the one of the most historical cities in the world. The Istanbul Cultural and Presence Committee in Turkey have 
declared some old areas of the city as an historical area for the protection of her old structure. Obtaining the silhouette of these 
areas is one of the steps of this protection procedure. The silhouette of the old city called historical peninsula and the both sides 
of Bosphorus are documented using photogrammetric methods. This documentation campaign will be repeated every three-year 
and silhouette changes will be controlled by the Istanbul Greater City Municipality. Rolleiflex 6008 metric camera was used and 
pictures at predefined stations are taken and stereo models of the related areas are obtained and evaluated by Phodis ST System. 
The geodetic measurements for the control points are done by the quickest and reliable surveying methods. The result of the 
project is the scaled and defined silhouette of the area. The obtained silhouette is compared with the last one obtained before 
three years ago and changes are documented. The silhouette is defined for all the campaigns as the projection of the 
photogrammetric obtained 3D silhouette onto the plane, which is vertical to the camera direction. 
1. AIM OF THE STUDY 
Istanbul is the one of the most historical cities in the world. The 
Istanbul Cultural and Presence Committee in Turkey have 
declared some old areas of the city as an historical area for the 
protection of her old structure. Obtaining the silhouette of these 
areas is one of the steps of this protection procedure. The 
silhouette of the old city called historical peninsula and the both 
sides of Bosphorus are documented using photogrammetric 
methods. This documentation campaign will be repeated every 
three-year and silhouette changes will be controlled by the 
Istanbul Greater City Municipality using these 1/500 scaled 
silhouette maps. The project has been put out to tender and EMI 
Mapping and Information Group has acquired the adjudication 
under the supervision of the Photogrammetry Department of TU 
Istanbul. The project consists of three different steps: 
• The 1/500 scaled silhouettes of the coasts of the 
historical peninsula using terrestrial photogrammetric 
methods 
• The photogrammetric documentation of the historical 
streets and public open places 
• The silhouette map production work to control the 
silhouette changes on the both sides of Bosphorus 
2. THE SILHOUETTE FEATURES 
The silhouette is a concept, which can only be fixed with 
predefined features. The silhouette belonging to a specific area 
can be obtained differently according to the predefinitions. The 
parameters of these definitions are the distance to the object, the 
height of the station and the plane, on which the silhouette are 
projected. By this project, the silhouette points are obtained 
by means of photogrammetric methods in the object 
coordinate system and transferred to the Macro station to be 
able to be drawn. The silhouette points are then projected on 
to a plane, whose specifications are predefined. By this work 
a plane perpendicular to the direction from the object to the 
camera has been chosen. 
3. DIGITAL PHOTOGRAMMETRIC METHOD 
Digital Photogrammetric methods have greater advantages 
compared to analogue systems as better stability (geometry 
and radiometry), greater accuracy, and the ability to process 
images. It is also possible to display vector data in the 
images on the screen and to produce transformed images 
(rectification, orthophoto). 
For these reasons, digital photogrammetric method has been 
chosen for the silhouette projects of Istanbul. 
A detailed plan was designed for the silhouette study of the 
ancient part of Istanbul and according to this plan 255- 
control points (Figure. 1) has been signalised on the Marmara 
and Golden Horn shore inside of the city walls. This ground 
control points has been measured with Total Stations and 
their coordinates established. And then GPS supported 
transformation to the land coordinate system has been 
realized. In this study, the photographs have been taken with 
Rolleiflex 6008 camera on the boat from the sea. The 
relation between the focal length of the used camera and the 
image formats is shown in Figure 1. Figure 2 shows the 
same area taken with different focal length objectives. 
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