Modem Methods for Using Single Images in Conservation 
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Fig.3: Typical manual sketch to be replaced or by a state of the art photomap, see Fig. 7 
3. OBTAINING GROUND CONTROL USING VIDEO BASED TACHYMETRY AND VERIFYING A4MX4M GRID 
Fig. 4.: Replacing of signalized points by video recording of the ground surveying in Patara (Turkey) 
It is liked to emphasize, the signalizing of controlpoints partly can be replaced by video recording the queue of ground survey points, 
when engaged with the reflector staff, see Figure 4. These controlpoints, can be clearly interpreted on the video screen and 
transferred to the corresponding synoptic photograph for, e.g., rectification purposes. It is also very important, clearly to assign the 
point number on the video tape, at least by voice recording. 
4. DIGITAL PHOTO MAP GENERATION, BASED ON THE MODIFIED FACET METHOD 
The facet method has been used in France until about 1970 in an analogue manner, even for precisely cadastral mapping purposes. 
The characteristic terrain surface is adapted by multiple polyeder projection. 
For a modem flexible application of a modified facet method, in particular to survey an Archaeological site, the “polyeder” can show 
a regularly (4 x 4m) grid as well as random edges, see Fig. 5. 
The edges of these polyeder pattern are marked with wooden colored sticks. 
The object surface must be suited to be adapted by a polyeder pattern 
The three dimensional coordinates of the regular or non regular situated edges of the polyeder pattern are set out and/or 
determined using the conventional terrestrial polar surveying method. 
Extremely low altitude aerial photography, successive taken with a amateur camera from a telescope beam of approximately 
10m height, must show the particular polyeder or grid plain of about 4 x 4 m in nature, as indicated by at least 4 corresponding 
marked points of the polyeder respectively of the grid. 
The exposure is verified from the ground using modem infrared control or ball exposure. 
Continuously the images, defining the polyeder, will be digitized and digitally rectified, based on at least 4 controlpoints, e.g., 
using the Rollei MSR rectification program. 
Of course an alternate method is analog optical rectification using a rectifier. 
Finally the rectified images are digitally or manually mosaiced to achieve the complete 
photomap of the archaeological site.