110 
Fig. 7 - (below) Mosaic of orthophotos with 
stretched meshes (medium altitude aerial 
coverage). 
Fig. 8 - (above) Orthophoto with overlaid D.T.M. 
and contour lines (grid 5x5 m. low altitude aerial 
coverage). 
representation. In these cases the digital 
photogrammetry, allowing techniques much more 
quick like the auto-calibration of non-metric camera 
images, or innovative like the orthophoto which can 
be used as support for updating the continuous 
changing situations of excavations, it dramatically 
facilitate the work of the experts. 
Meaningful improvements, in the reliability of the 
orthophoto projection, they could be reached by: 
• Increasing notably the overlap up to 85-90% 
(procedure always advisable in the relative low 
altitude coverages); 
• Directing, when possible, aerial coverages 
along the most evident altimetric jumps (scarp 
borders, trenches, eroded courses of rivers 
etc.); 
• In alternative, completing with a series of 
coverages orthogonal to those previously 
Fig. 9 - 
site dui 
altitude 
1:200). 
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overlap 
triangula 
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