Network of control points 
The plannning of survey has previewed the location of a 
network constituted by four stations around the monument, and 
one on the entrance threshold with consequent materialization 
and a monographic card for each station. (Fig. n. 1) 
The network of control points has been realized using the Total 
Station NIKON NPL-820 equipped with laser without reflecting 
prism. From every station, the positions of the single stations 
and an high number of points have been surveyed for the 
photogrammetric models. 
All control points have been referred to the same local reference 
system with opportune procedure of rigorous compensation. 
  
  
  
  
  
Figure 1: Network of control points 
The monument had been preventively equipped of affixed 
targets in all the lower part of the Church. For the other ones 
easy recognizable points of the same monument for the 
photogrammetric survey have been found. 
Laser survey 
A higher number of targets which supply a better reflectance 
have been used for the Laser Scanner survey. 
The survey has been carried out by placing the Riegl Laser 
Scanner Lms-Z210 in the same points of topographical 
network around the Church setting the instrument in order to 
acquire a grid of points with equidistance of 2 cm with a 
vertical angle of 80° and with the necessary amplitude to frame 
the Church according to the software of the instrument 
management. 
After a few minutes of surveying the Scanner has pointed out a 
dense cloud of points ( 700.000 ca.) so that it has been possible 
to see the result of acquisition in the same countryside. 
On the Notebook screen it is possible to visualize the acquired 
cloud of points in several modalities, which give the perception 
of the building shape in all the three dimensions. The same 
software exports the survey in different kinds of files such as 
the DXF which we have used in the following elaborations. 
Photogrammetric survey 
The architectonic building can be well investigated through 
photogrammetric means. For this reason we have carried out 
several photos with different photographic instruments in order 
to compare results and procedures regarding both the 
difficulties of execution and allowed accuracy. 
The first metric survey has been carried out, using a Zeiss Jena 
UMK Metric Camera (photograms 13 x 18 cm), by 5 couples 
of photograms (Fig. n. 1) for the realization of stereoscopics 
models: 4 models in axis with the lobes of the plant and the 
fifth one in adding for the main façade. 
In the same time another survey has been carried out, using a 
Rollei 6006 Semimetric Camera (6 x 6 cm photograms) with 
calibration, obtaining 5 couples with 80mm focal length and 
other 4 couples having a 40mm focal length. 
  
Figure 2: UMK 13 x 18 Photogram 
Other two surveys have been realized: 
the first one with Silvestri non-metric Film Camera (n. 8 
photograms 4" x 5") focal length Super Angulon 65mm, 
the latter with non-metric digital 3 Mpixels camera (7mm focal 
length ). 
The images recorded at the maximum resolution allowed by the 
camera firmware have produced 1,5 MB files for each one. 
Images digitizing 
The photograms realized with chemical film cameras have been 
digitized with the Wherli RM3 digital photogrammetric Scanner 
by 20 micron resolution, obtaining Tiff files of about 200 MB 
for the UMK photograms. 
Photogrammetric model with metric camera 
The files have been used to realize stereoscopic models through 
a digital plotting station constituted by SISCAM 
STEREOMETRIC plotting software with a suitable stereo 
polarized screen. 
Once realized the stereoscopic model with procedures of 
necessary I. and E. orientation we have obtained the Digital 
Elevation Model of the Church through the automatic 
correlation of images with the ADA module of the Stereometric 
software. 
The system has been set it in order to obtain a grid of 5x5cm 
for one portion of the model obtaining thus a very interesting 
cloud of points but with very long times of elaboration. 
The obtained points have been exported in DXF files in order to 
investigate the features and to compare them. 
The following images display the result of the cloud of points 
extraction with the automatic correlation of image in digital 
photogrammetry (Fig. n. 3) and with Laser Scanner (Fig. n.4). 
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