CIPA 2003 XIX th International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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The future of laser scanner methods would seem to involve 
integration with digital photogrammetry. 
This integration is done in the production of the following 
records: 
• Orthophoto: initially, we attempted to use simple digital 
orthophotos by using DEM records from laser scanner points, 
as shown for example in some texts written up on the facade 
of the St. Mark's Basilica (Guerra 2002). The problems arise 
on the use of DEM generated with the usual algorithms used 
for DTM (Kriging) without considering the discontinuousness 
present in the architecture (fig.2). 
fig. 2 ortophoto of a part of the façade with evident errors due 
to architectural discontinuities 
• True orthophotos: these represent the evolution of the 
previous form, based on the use of several photograms and a 
precision DEM (Rinaudo, Dequal 2001-2003). See the 
example of a true orthophoto of the portal of the Basilica 
realised by the authors (fig.3). 
• Solid image: (Dequal 2002-2003) these have enormous 
potential as they leave interpretation of the image up to the 
individual engineer by providing the possibility of directly 
extracting the measurements. 
• Rendering 3D model: these are the dressings with RGB 
radiometric information of 3-D models for surfaces or solids 
generated in a number of ways (mesh, parametric surface, 
geometric primitives). 
As we can see from the examples provided, in all the 
applications that have been applied and tested in St. Mark's 
Square, the photogrammetrist does not show a systematic 
consideration of the radiometric calibration of the digital image. 
Today, "colour" is considered one of the "themes" to apply to 
the representations that enable precise indications on the state 
of decay of the material (for example, the black crust) but it is 
also fundamental in the characterisation and recognition of the 
materials. 
If we think about the evolution of the use of photography in the 
metric survey, we can see how the stereo pairs 20 years ago (the 
authors remember their early photogramme trie experiences) - 
when rectifications were made using black and white film, shots 
that the photographic historian, Italo Zanier called 
"architectural photographic signposts" because of their poor 
aesthetic quality - have evolved to analogue and digital 
photographs where the photographic quality has become better 
and better. This need to value the photographic quality in 
addition to the metric rigor is associated with the higher 
diffusion of photoplans and orthophotos. The photogrammetrist 
has gradually become more and more a photographer. 
Now, the photographer and photogrammetrist must find the 
metric component of his images, so solid images will become 
more metric and the rendered 3D models will become real 
scientific colour maps. 
fig.3 Surface model and true orthophoto of the central portal of the St. Mark’s Basilica