CLOSE RANGE ORTHOIMAGE USING A LOW COST DIGITAL CAMCORDER 
E. Tsiligiris 3 , M. Papakosta 3 , C. Ioannidis b , A. Georgopoulos c 
3 Surveying Engineer, Post-graduate Student, National Technical University of Athens - tsili@hol.gr 
b Ass. Prof., Lab. of Photogrammetry, National Technical University of Athens - cioannid@survey.nyua.gr 
c Prof., Lab. of Photogrammetry, National Technical University of Athens, Greece - drag@central.ntua.gr 
KEYWORDS: Digital Camcorder, Close Range, Orthoimage, Heritage Recording 
ABSTRACT: 
Video recording and digital photogrammetry are usual techniques to achieve monument morphological and metric documentation 
respectively. An all at once approach provides significant cost and time saving, especially when dealing with complicated objects, 
which demand multiple photography for their full coverage. Based on this consideration, this paper examines the possibilities of 
using a low cost digital camcorder to supply imagery in order to create large-scale orthoimages of a site with adequate geometric 
accuracy and radiometric quality, through the usual photogrammetric procedures. The first step of this research is the calibration of 
the camcorder at an appropriate test field applying a bundle adjustment. Then, an application took place on one side of the Gate of 
Adrianos monument. Still images were captured through a DV card. The manual generation of a DSM and the creation of 
orthoimages derived from different initial still images took place in a SSK. Z/I Imaging digital photogrammetric workstation. A 
comparison of the achieved accuracy, completeness and cost of this method’s products with the conventional orthophotos of the 
monument, which were derived from photos taken with photogrammetric cameras, was made. Finally, limitations of the specific 
camcorder’s use, for the geometric documentation of the monuments, are also described. 
1. INTRODUCTION 
During the last years digital photogrammetry became a very 
useful tool not only for site recording but especially for 
architectural geometric documentation. Many applications exist 
in the relevant literature, in which metric or semi-metric 
analogue cameras and non-metric digital cameras are used. 
Video is an other alternative tool for the documentation of 
monuments, in various levels, starting from simple digital 
image recording up to the 3D extraction of metric information. 
Videometry has developed significantly since 1990 mainly in 
the field of industrial applications or for the monitoring of 
dynamic phenomena (Tournas, 2003), and in the field of 
architectural applications as well. The video capabilities for the 
recording and visualizing both real and computer generated 
scenes or the readily available output of every CAD, 
photogrammetric or visualization tool or even the production of 
geo-referenced 3D video (Sechidis et al, 2001), show that it is a 
powerful and promising tool for archaeological applications. 
Moreover, the development of the Mini-DV and Micro MV- 
Network technology is more than rapid making the digital 
camcorder to be a low cost solution. 
According to the above it was decided that a test should be 
performed. The main aim was to investigate the capability of 
digital amateur videos for providing usual photogrammetric 
products, such as an orthoimage. The application of this work 
was carried out on the east side of the Gate of Adrianos 
monument, considering as main theme of the camcorder’s 
orthoimage, part of a column capital. This monument was built 
in the 2 nd century by the Roman emperor Adrianos at the 
entrance of the ancient city of Athens. This impressive 
construction measures approximately 14 m in breadth and 17 m 
in height. It consists of two parts. A lower one which presents a 
majestic arch - the main city gate- and an upper part, which is 
lighter, ornamented with pillars. Today it is located at 
Figure 1. Grayscale Orthoimage of the east side of Gate of 
Adrianos and an ortho-detail of the specific column 
capital 
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