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CALIBRATING AND USING AN OLYMPUS CAMERA FOR BALLOON
PHOTOGRAMMETRY
T. M. Celikoyan“, M. O. Altan“, G. Kemper b G. Toz“
“ ITU, Division of Photogrammetry, 80626 Maslak Istanbul, Turkey, (mcelikoyan, oaltan, tozg)@itu.edu.tr
b GGS, Kämmererstr.14, 67346 Speyer, Germany, kemper@ggs-speyer.de
WG7- Photography
KEY WORDS: Archaeology, Three-dimensional, Visualization, Zoom Camera, Calibration
ABSTRACT:
An Olympus C4040 digital camera has been calibrated by using BAAP Software for taking aerial photos. This standard camera is
good priced, has got a high resolution and a small weight. As a speciality, the platform was based on a Helium-Balloon of 2,5 m in
diameter. The camera has been mounted under the balloon by using a gravimetric cardanian platform, which has been designed in
order to hold the camera always in nadir position by its own weight, fixed on 2 independent axes. The camera has been selected
because of its technical specifications such as remote controller and video output. Using the remote controller, photos are taken by
an operator from the ground, which has got a video monitor showing the view of the cameras lens hanged under the balloon. The
balloon has been controlled by three operator, using ropes.
The biggest problem of this application was the sensitivity of the balloon to the wind. The more intensive wind the wind blew, as
more rotation and movement of the balloon and the camera took place. In such cases, angles of the photos force big efforts in the
photogrammetric orientation for getting usable adjustment. Because of this, we had to use calm weather conditions for taking the
photos, mostly in the morning. The study area was an amphitheatre in the antique city of Patara. Before taking the photos, a flight
plan has been developed. The photos have been taken from an altitude of 30 to 40 meters. Ground resolution was fine for the
photogrammetric work with an accuracy of < 5 cm. Advantage of this system is the small price, the immediate available data and the
possibility to undertake daily updates to monitor the excavation process.
1. INTRODUCTION
In 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.
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.
However with some additional parts, the consisting system can
be used for special purposes.
2. SYSTEM OVERVIEW
The system contains two main units. As illustrated in Figure 1,
these are;
Ground Control Unit
Figure 1. System overview
Flight Unit
- Ground Control Unit 2 .1 Flight Unit
In the flight unit, there are three main parts. These are;
Helium Balloon
Camera Platform
Camera