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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