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Close Range Photogrammetry in Support of Architectural Restoration and Structural Works 
2.2 The lateral façades 
The surveys of the lateral façades have been of remarkable difficulty for one series of reasons, firstly of logistic nature. It was 
impossible to use an elevator to take photograms at different height due to the limited accessible spaces and the strong traffic. So the 
photograms have been acquired from the windows of the frontal buildings of the two façades with insufficient possibilities of 
manoeuvre as far as the scale of the photograms and the position of the shoot points. Moreover, the same logistic problems not 
permitted the realisation of a good quality traditional topographic survey for the determination of outer orientation parameters: the 
polar method was adopted using reflective targets temporarily placed over more than 30 natural points easily recognisable on the 
photographs. The drawing of façade B (on the right side of the building), produced in 1:100 scale, is shown in fig. 5. The co 
ordinates of the façade points were transformed in the reference system adopted for the main façade by a 6 parameters 
transformation, using common points. 
Another survey was finally dedicated to the top of the church, with the survey of the exterior of the dome. 
2.3 The exterior of the Dome 
For the top of the church a topographic survey was carry out, integrated by direct measurement in the inaccessible parts for a greater 
detail description. Due to visibility problems, spatial intersection techniques were often impracticable and then in a first step it was 
measured with total station Leica TC2000 one closed traverse of 5 vertices covering the full area with the lantern zone exclusion. 
The closed traverse was adjusted and the results inserted in the main reference system using some tie points. From the vertices of the 
traverse a polar survey was then irradiated concerning about 100 points characterising the main geometry of the dome (fig. 6). The 
acquired points were integrated with a remarkable number of directed measurements to describe the structure details. The network 
and the final drawing are shown in figure 6. 
Figure 6: The polar survey for the exterior of the dome (a) and the final drawing (b)