105 
Fig. 7 - Metric camera settling in the upper side of 
the aisle of the Ospedale dei Crociati. 
2. Archaeological excavation documentation 
regarding the refurbishment of an historical 
building 
During the refurbishment of Ospedale dei Crociati di 
Molfetta (Bah) the need for a detailed 
documentation of the bottom of the archaeological 
excavation beneath the nave and the aisles. 
The presence of masonry marks of ancient 
structures, pillar foundations, water basins, water 
downflow canals etc., made the photogrammetric 
survey project really complex. It was decided to give 
priority to the production of a coverage with nadiral 
shots in a photo-scale suitable for plotting up to 
1:20. 
The need for the usability of the survey also by art 
historians, not skilled to operate on a 3D vector 
graphics, suggested the production of a 
orthophotomosaic of the whole surface involved in 
the excavation. 
2.1 Design and execution of photogrammetric 
analysis 
The frame scale attained, of about 1/40-^1/50, is far 
larger than the minimum required and was 
conditioned by the available distance. 
A D.E.M., with a 30x30cm grid, has been manually 
constructed with an analytical stereoplotter Siscam 
Stereocart after about a fifteen hours work. The 
orthophotoprojections have been executed with the 
S/W StereoView (Nikon Instruments S.p.A.), and 
there wasn’t any operational difficulty, apart from the 
size of the flies that compose the whole b&w 
orthophoto-mosaic (about 70MB). 
3. Conclusions 
The experiences made demonstrate how the 
production of single orthophoto, and of mosaic of 
ortophotos, is really useful for users not skilled to 
take the most of the capabilities of 3D vector 
graphics. The interpretation of digital orthophotos 
seems to be much easier for the not skilled users, 
but contains small areas where the pixel distribution 
is less clear. The reference is to all the zones where 
the photographic shadows, together with the sudden 
altimétrie variations, require the completing of some 
areas that lack in photographic information, in all 
this areas the final image should be edited and 
cleaned, substituting the orthoprojected pixels in the 
adequate performance, also enough fast. 
The result showed a good quality, being the 
analysed surface without any photographic 
discontinuity and shadows, together with the high 
density of D.E.M. according to the characteristics of 
the altimetry of the object. 
The settling of the camera, also in this case a UMK 
10/1318, was made with scaffolds constructed at the 
vaults intrados at about 4-7-5 m from the floor, with 
an auto-built support suitable for nadiral 
photographs.