The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B5. Beijing 2008 
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(military exclusion zone), no measurements outside the temple 
area could be arranged. 
The first step was to use the Riegl LMS-Z420i (figure 3), a long 
range terrestrial laser scanner, with a maximum range of up to 
800 meters. Because of the rough terrain and the military 
restrictions it was not possible to get a complete point cloud of 
the requested area. So the idea for a photogrammetric mission 
flight was bom to fill the existing gaps of the point cloud and to 
extend the captured area (figure 4). 
Figure 3. Riegl LMS-Z420i 
Surface covered by Aerial 
Photogrammetry 
■ 
Surface covered by TLS 
Figure 4. Surface Measurements TLS / Aerial Photogrammetry 
2.2 Aerial Photogrammetry 
The available flight crew did not have any experiences in flying 
for aerial survey, therefore the application of a GPS based 
navigation system was strongly recommended. For that, the 
EasyNav System was chosen, which is part of the LEO system, 
developed by Bochum University of Applied Sciences (Heimes 
& Brechtken, 1992, Baeumker et al., 1997, 1999). This system 
is especially designed for small and medium photogrammetric 
systems. The complete hardware is rugged assembled under 
military specifications. For the Athribis project only the 
navigation part of LEO was used, the complete hardware is 
shown in figure 6. This system can be operated without any use 
of mouse or keyboard during the flight. If required the 
navigation system can be extended by DGPS / INS and also 
with a stabilized mount. The mount for small and medium 
sensors is shown in figure7. 
Figure 7. Stabilisation Mount 
The mission planning was also done with EasyNav. It had been 
planned to acquire the desired area with a ground resolution of 
25 cm, and smaller areas with 10 cm and also with 2.5 cm. To 
avoid unsharpness, especially at GSD = 2.5cm, it is necessary 
to reduce the ground speed of the sensor platform. The 
maximum distance during exposure should not be larger than 
half a ground pixel. With a shutter speed of 1/1000 sec the 
maximum ground speed is: 
Taking aerial images in Egypt, by a foreign university, is a 
more than complicated process and can only be successful with 
good connections and supporters. In cooperation with the 
Egyptian military a helicopter flight was realized. Because no 
photogrammetric equipment was available on the location, the 
complete camera-, navigation- and data processing hardware 
and software had been brought from Bochum. For the aerial 
images a Rollei AIC (Figure 5) with 39 MPix was used. 
Technical specifications are as follows (table 1): 
Focal length: 
51 mm 
Shortest Exposure Time: 
l/1000sec 
Sensor format: 
7228 pix by 5428 pix 
Table 1. Sensor specifications 
Figure 5. Rollei AIC Figure 6. Nav-System EasyNav 
0.5 • 2,5cm • 1000 = 12.5 mete ^ ec a 24knots 
This maximum speed is too slow for using airplanes, but with a 
helicopter it can be realized. For data processing on the location 
a powerful notebook with a high resolution display was used. 
Based on information extracted from Google Earth (Figure 8), 
all mission planning were already completed in Germany. 
The photogrammetric work was done with Socet Set 5.3 by 
BAE Systems (BAE Systems, 2008). The complete system, 
consisting of camera, navigation system and photogrammetric 
workstation, was carried in one suitcase as hand luggage to 
Egypt. 
For the mission flight only 2.5 hours were arranged. The 
helicopter, a Russian MI-17 (Figure 9, maybe a little bit 
oversized for such a compact photogrammetric system), was 
located in Luxor. The ferry flight to Athribis and back to Luxor 
took 1.5 hours, so nearly 60 min were left for the real 
photogrammetric flight. There was no possibility for a test 
flight or to teach the pilots. Only during the ferry flight to 
Athribis some kind of training was done. These, of course, were 
no perfect conditions, but the pilot did a very good job. Because 
of the limited time schedule it was not possible to collect all 
images, but enough images could be taken in all three planned 
flight levels. To be on the safe side, the low level flight with a