digital cameras that utilize the body of the 
classical film cameras. They consists of a back 
that must be added to the classical camera and 
that permits to register the image directly in the 
digital form without trasforming it into a video 
signal. 
Anyway at the moment also these instruments 
(Kodak, Rollei) cannot give a resolution on the 
acquisition of the images similar to that one 
given by the system composed by the 
photogrammetric camera and the scanner. 
3 - TO PROJECT AN IMAGE 
After the acquisition and memorization of the 
image the problem still exists of the intervention 
on it as a deformation that can be considered as a 
projection. This means to deform the image not 
only on the plane of the photogram but on each of 
the infinite planes of projection. 
Without considering the analytical aspect, we can 
reduce the problem to its minimum: the principle 
is then to think at the projection of a generic 
image on a surface of generic geometrical shape. 
This has, as a consequence the overcoming of the 
conception of bidimensionality of the image. 
It happens a convergence between the disciplinary 
approach of the conservative intervention on the 
surfaces and the disciplinary approach on the 
survey itself. 
In fact a relation more and more closer with the 
third dimension appears. It creates a new bridge 
between two worlds that, in the history of the 
restoration, had follow different assumptions and 
operative choise. The first one of the structures 
and the second of the surfaces, decorated, 
plasted, with mosaic...., that too often has been 
reduced to the images. Infact often the matter, 
which introduced a great cultural thickness, also 
physically, is negleted. 
Here is the importance to have projected an image 
of the cupola on the spheric surface (Fig.3). The 
teorical aspect is underlined, in a strong way for 
the purpose of a metodology, with the immediate 
developments and the application in the ambit of 
cataloguing. 
The using of a programm, that doesn't intervene in 
the analytical problem but manage the projection 
of images on surfaces, has been the preamble to 
verify the vision from different points of view of 
the image. This one regenerates on teh surface 
projecting then itself on the ideal plane of the 
video and so of the point of view (Fig.4 Lower 
part). 
What we said becomes essential in presence of 
surfaces that have hidden points that ask for this 
operation, to make them usable. These points are 
present at the same time in the same object but 
aren't at the same time visible (Fig.4 Upper 
part). Therefore the research opens new frontiers 
in the study of the digital images that doesn’t 
involve only the analytic-metric aspect. 
The quality of the photogram and of the image 
represent an essential parameter for their use in 
a project of conservation. For this reason the 
possibility to read the phenomena of 
deterioration, the formal values, and the analysis 
in general terms have in the photography and in 
the image the principal reference for the 
immediate reference to the object that 
characterize them (Fig.4 Upper part). 
An important consideration is about the limit of 
approaching and of the resolution of the image in 
relation with the ratio of magnification. The last 
one is directly proportional to the need of the 
operator to evaluate the phenomena of alteration 
and of deterioration and inversely proportional to 
the need to utilize the traditional scale of 
representation (1:50) as a limitation of the 
number of takens referring to the finalities of 
the drawing to plot.