CIPA 2003 XIX 11 ' International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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3.2 The modern documentation 
After the end of the war. access to the castle became secure. 
There was a need to manage to realize a complete 
documentation of the unreachable parts of the castle (basically 
the eastern elevation over the valley). That’s why a helicopter 
flight was scheduled in 2003. Aerial oblique views were taken 
(figure 1) in that flight. They were composed of digital images 
(Nikon Coolpix 5000, 2560x1920 pixels) and film-based small 
format color slides (Nikon F3, Nikkor lenses, 55 mm). Last but 
not least, a complete documentation requested terrestrial views 
of the castle; digital images and again film-based small format 
color slides were taken. Thanks to this exhaustive 
documentation, three-dimensional restitution was possible. All 
the modern documentation was produced in one day. 
Figure 3. Example of modern photo 
(Nikon Coolpix 5000, 2003) 
3.3 The topographic survey 
On that same day, while photos were being taken, a team of 
geodetic surveyors installed reference points on the ground and 
elevations of the castle. These points (figure 4) were easy to 
identify on the photos. A total-station was used by the 
surveyors to measure the reference points. This generated three- 
dimensional coordinates for these points. 
Figure 4. Examples of targets used for the reference points 
3.4 The AutoCAD documentation 
The first topographic surveys conducted during the preliminary 
study were not very accurate due to the difficulties encountered 
in trying to access some of the areas of the castle. These first 
surveys were performed using GPS and tacheometric 
techniques. The AutoCAD maps (figures 5 and 6) used to 
establish the tender documents for the restoration of the castle 
were based on these surveys. The inaccuracies of these surveys 
did not represent a major problem for the restoration of the 
visible areas of the castle. Flowever, these inaccuracies 
prevented us from computing the exact position of the 
archaeological hidden remains. We plan to generate a new 
AutoCAD documentation showing the surroundings of the 
castle and the archaeological hidden remains that should be dug 
out (§5). 
Figure 5. Example of 2D AutoCAD map from the tacheometric 
survey of 2002 (level 4 of the castle). 
Figure 6. Example of 2D AutoCAD section. 
4. PHOTOGRAMMETRIC DATA PROCESSING 
4.1 Multi-image photogrammetry 
Photogrammetric solutions (Grussenmeyer et al., 2002) are 
either based on the processing of single images (e.g. image 
rectification of plane objects), stereoplottings (for stereopairs of 
photos), or multi-image restitutions when a set of convergent 
photos of an object is available. The last solution has been 
chosen for our project in order to process in one block the sets 
of photos taken from different cameras. We used the 
PhotoModeler software package from EOS System (Canada), 
well known for its applications in architecture and archaeology. 
The preparation steps in order to process the images were the 
following: 
- definition of the “camera” file for each type of camera: the 
« camera calibrator » module of PhotoModeler has been used; 
- for the archive images, an approximate camera file has been 
edited - for further “on the job calibration”;