BALLOON PHOTOGRAMMETRY FOR CULTURAL HERITAGE
M. O. Altan *, T. M. Celikoyan“, G. Kemper" G. Toz*
? ITU, Division of Photogrammetry, 80626 Maslak Istanbul, Turkey, (oaltan, mcelikoyan, tozg)@itu.edu.tr
® GGS, Kammererstr. 14, 67346 Speyer, Germany, kemper@ggs-speyer.de
SS 4: CIPA — Low-Cost Systems in Recording and Managing the Cultural Heritage
KEY WORDS: Archaeology, Three-dimensional, Visualization, Camera, Calibration
ABSTRACT:
Documentation and measurements on historical buildings are mostly connected with close-range photogrammetry for high resolution
in order to analyse the detailed structure of the objects. Classical flight campaigns are expensive, limited by the resolution or
restricted. An alternative with immediate access to the data is the use of a helium-balloon based platform with digital camera.
For a project in the southern part of Turkey has been developed a system with a He-Balloon, a digital camera, a control-monitor and
a mechanic stabilization. As digital camera was chosen an Olympus Camedia 4040 with 4 Mega-Pixels, which has been calibrated.
The Camera was fixed in a triangle frame on 2 axes, so that it had always nadir view. The triangle frame was fixed with 6 ropes
below the balloon, and to the ground with 3 ropes, one carried a video and control wire. The video signal of the cameras view was
sent to a monitor and the remote control of the camera was also solved by wires.
Then a flight-campaign in August 2002 was made over an excavated historical theatre in the former city of Patara, the former major
port of Lycia, located at the mouth of the Xanthos River. In the presentation we want to show you the technical solution and the
results of this campaign. The accuracy of the aerial images was better than 4 cm in position and height, the digitising however
complex, related to the objects structure. The 3D-Vector data built the base of a fine DTM. Orthophotos have been created in order
to add information the digitised results.
1. INTRODUCTION
Helium
Balloon / /
[n photogrammetric application, image acquisition is one of the
most expensive steps. Especially if aerial images must be taken,
the expenses are always high because of the high-cost of
aircraft campaign. In some cases, other solutions for aerial
imagery such as kite, balloon and remote-controlled model
helicopter or aircraft can be the optimum solution (Leloglu et
all). These types of solutions can be used, if the area of interest
is small and non-metric cameras are enough accurate for the
job. 7 Y Flight Unit
N — Control Ropes
Camera Platform
Camera x
f RR
In this study, a low-cost solution for low-altitude aerial
photogrammetry is represented. The system is designed for :
general purposes of low-altitude aerial photogrammetry. f E
However with some additional parts, the consisting system can e Re
be used for special purposes. / : Lr Shug ‘
; "Monitor _ :
2. SYSTEM OVERVIEW Main Control Repe ;
with video |
. . ; . . . and shutter cable |
The system contains two main units. As illustrated in Figure 1, : Ce
these are; Figure 1. System overview
- Flight Unit 2.1 Flight Unit
- Ground Control Unit
In the flight unit, there are three main parts. These are;
= Helium Balloon
= Camera Platform
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