CJPA 2003 XIX 11 ' International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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- edition of the control point table (from the geodetic survey); 
- scan of the film or paper-based images (for the set of archive 
images and the color slides from the Nikon F3 camera). 
The basic steps in a project performed with PhotoModeler are : 
- choice two or more overlapping photographs from different 
angles of the object; 
- use the point and line tools to mark on the photographs control 
and tie points; 
- reference the points by indicating which points on different 
photographs represent the same location on the object 
(homologous points); 
- process referenced data to produce 3D model; 
- check the adjustment and view the resulting 3D model in the 
3D viewer; 
- extract coordinates, distances, curves, surfaces, texturs etc. 
within PhotoModeler; 
- export the 3D model to rendering, animation or CAD 
program. 
4.2 Calibration of the cameras 
Four types of images are used for this project: 
- images from Nikon Coolpix 5000 in the extreme positions of 
the zoom (7mm and 21mm). This camera was calibrated in the 
two positions using the calibration grid proposed in the 
PhotoModeler software (module "camera calibration"); 
- images taken with a traditional reflex camera Nikon F3, 
equipped with an objective Nikkor 55mm. The calibration was 
carried out like previously after scanning the slides; 
- images of 1930-1936 scanned with a resolution of 900dpi: 
unfortunately no photogrammetric information on the 
characteristics of the cameras used has been found until now. 
Several types of glass-plates-based cameras with focal distances 
of 20 to 30cm were used at that time for the acquisition of aerial 
and terrestrial views (Roussilhe, 1936). 
4.3 Adjustment of the block of images of 2003 
More than 130 images were realized in spring 2003 with the 
Nikon F3 and Nikon Coolpix cameras (a hundred images on the 
ground and about thirty in the helicopter). A first block of 18 
oblique views of the castle was oriented in June 2003 using the 
control points materialized on the ground by targets (figure 4). 
Standard deviations of about 10 cm on the co-ordinates of the 
points measured on the images have been obtained. We then 
selected in this project ten visible points simultaneously on the 
images of 1931-1936, in order to define approximations of the 
photogrammetric parameters, and to calculate a block based on 
a selection of these archive images. 
4.4 Adjustment of a block of archive images 
Initially we selected 4 oblique photographs (scales of 1/1000 to 
1/2000) in order to document archaeological vestiges of the 
North and West parts. The approximate values of the internal 
and external orientations of the archive images have been 
computed within the module "process & autocalibration" of 
PhotoModeler with the help of control points defined in §4.3. 
4.5 Merger of the two projects and preparation of the 
restitution 
At this stage, the two separately calculated projects are referred 
to the same reference system. The process of merging (of 
several projects) proposed in the PhotoModeler software allows 
the restitution of three-dimensional elements simultaneously on 
the photographs of 1936 and 2003, and to superimpose and 
display these results within a unique project. 
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Figure 7a. Overview of the camera stations and the block 
configuration after the exterior orientation 
Figure 7b. Aerial view of 1935, allowing to locate the camera 
stations of the figure 7a 
5. RESTITUTION OF THE HISTORICAL 
STRUCTURES NOWADAYS DISAPPEARED 
From the block of images previously oriented, the restitution 
initially carried out in 2D in Autocad (e.g. fig. 5 and 6) will be 
enriched by a 3D restitution corresponding to the objectives of 
the documentation. We are then able to calculate and draw the 
visible structures on the aerial and terrestrial photographs of 
2003 by digitalizing on the images (fig. 8). 
One will proceed in an identical way on the archive 
photographs to measure the archaeological structures currently 
covered by the remains of the war, or to plot in 3D parts of the 
castle currently embanked or destroyed (fig. 9).