case in point of St. Mark's Square and its facades, where the 
only valid and consistent representation could be a 3D 
orthophotograph, which provides the most complete vision. 
  
    
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Figure 1 First point cluods 
Here we find a similar problem, to a different scale, in the floor 
mosaics of the Basilica of San Marco. The problems lie in the 
conservative restoration done on the floor which has required a 
3D reproduction to a 1:1 scale both in order to identify and 
replace damaged parts, as well as to install them while 
maintaining the characteristic altimetric irregularities, typical of 
the floor. It is clear that a strictly "plane" floor would not reflect 
the historic veracity to which we are accustomed . 
Here then, we have a modellation using a laser scanner, 3D 
orthophoto and an automatic extraction with altimetric profiles 
for constructing templates to a 1:1 scale of the museum floor 
(measuring about 2000 m2). The object of application of the 
techniques proposed which must measure up to the economic 
and scientific aspects. 
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Figure 2 Figure 1 Superinposition of clouds of test area: 
1.452.044 points. Point acquisition using laser scanners on 
several sample areas and on several samples that are significant 
by type, particular discontinuous morphology, and appropriate 
scale of representation: cultural sites, architectures, building 
units, elements, vaults and continuous mosaic surfaces, floors, 
facades, curtain walls and elevations on squares, at different 
scales, from the architectonic to the urban, archaeological 
complexes up to fragments and objects. 
  
    
  
  
  
  
  
  
Figure 3 Outline of takens. 
Camera Rollei D7 Metric (digital): Figu 
- sensor 2/3" CCD-Chip with 2552x1920 pixels; 
- lens Rollei D-Apogon f=7 mm (equivalent to 28 mm for 
35mm) 
Surveyed test area 60 mq, 21 takens, 3 stripes. 
1 pixel = 3.5 micron 
1 ground pixel = | mm 
Longitudinal cover60% 
Transverse cover20% 
Takens dimension: ~1.9 m x 2.5 m 
Test area -80 ma. 
Expected total takens : 1700, total area 2600 mq. 
  
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Figure 4 Rollei D7 Metric 
  
Figure 5 First strip of the test area . 
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