DOCUMENTATION OF ARCHAEOLOGICAL RUINS AND STANDING MONUMENTS
USING PHOTO-RECTIFICATION AND 3D MODELLING.
F. Summers ^ *, N. Atalan a , N. Aydm a , O. Baraga? a , G. Ugar 2
a The Kerkenes Project, Faculty of Architecture, Middle East Technical University, Ankara, Turkey -
fsummers@metu.edu.tr, natalan@isbank.net.tr, ozge@metu.edu.tr, gulnurucar@yahoo.com.
KEY WORDS: Archaeology, Cultural Heritage, Photogrammetry, Photo-rectification, G1S, 3D Modelling, Digital Photography,
Virtual Reality.
ABSTRACT:
Photo-rectification and 3D modelling offer a wide range of methods for the study and presentation, to a variety of audiences, of both
urban features and standing monuments at archaeological sites. Ever more powerful software and hardware are continually pushing
forward the limits of performance while electronic publication, on CD-Rom and through the World Wide Web, allows quick and
easy dissemination of results. This paper presents a study at the METU Faculty of Architecture, made possible by a METU research
grant (AFP2000), in which staff and students worked on different techniques for recording and surveying urban and architectural
elements and reconstituting them in a virtual environment. The studies include examples from Kerkenes, a large Iron Age city in
Central Anatolia, where well-preserved elements of defensive stone structures together with extensive stone paving were revealed, a
portion of the standing Byzantine to Ottoman walls at Ankara Kale and, finally, multi-period remains of Napoleonic to WWII
defences located on a small islet off the south-east coast of Mauritius. Software employed are (i) AERIAL, a simple rectification
program designed for non-experts working on desktop computers, (ii) PhotoModeler and (iii) GIS (Geographical Information
System) software, including ArcView and ERDAS Imaging. These studies have made considerable and significant progress towards
demonstrating the potential of IT (Information Technology) and GIS tools in the study of architectural and urban elements within
both the historical and the present environment. The methods and techniques could equally well be used to make visual projections
of active and intrusive architectural conservation and restoration programs.
1. INTRODUCTION
New software and improvement in hardware continually push
forward the limits of performance in the application of photo
rectification and 3D modelling. Electronic publication of
results, on CD-Rom and through the World Wide Web, allows
for rapid and easy dissemination of results. The aim of these
studies, conducted on a wide variety of projects, was the
development of techniques in photo-rectification and 3D
modelling that would have a broad range of applications in both
urban and architectural studies. The Kerkenes Project team has
pioneered employment and collation of several different
methods for surveying, recording and analysing urban elements.
Recent results show that Information Technology provides
numerous, continually developing, tools which the city planner
and the architect can use in studies of the built environment, be
it historical or contemporary. Examples have been taken from
several ongoing projects concerned with archaeological, urban,
architectural and environmental studies. The project has
focussed on:
1. The use of various techniques for recording and
surveying urban and architectural elements, both historical
and contemporary;
2. The representation of data and results in a virtual
environment;
3. Virtual reconstitution of urban and architectural
elements within the areas of study;
4. Traditional and electronic publication of the results.
2. SURVEY AND RECORDING TECHNIQUES
2.1 Plans and Elevations of Stone Walls
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Figure 1. Rectified photographs are imported into AutoCad and
cropped to form a photo-mosaic of the wall elevation.
Stone walls are tedious to record when accurate scale drawings
that show each stone are required. Digital photography and
rectification can greatly reduce time expended on detailed
recording in the field. One example chosen for this study was a
stretch of walling (Fig. 1) revealed by a machine dug trench at
the bottom of the Kerkenes Dag to tap water to the village of
$ahmurath. This feature, perhaps of historical value, was
exposed only for a short time and working conditions were
difficult. Rectification with AERIAL 5.3 involves creating over
the wall surface a net of control points marked with chalk,
paper or in some other suitable way. Strings can also be used to
mark the triangles formed within the net. In cases where the
surface comprises a combination of different planes it is
Corresponding author.