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1) procedure of referencing points from several photos; 
2) identification of plan trough reference points; 
3) realization of line as geometrical patch of points; 
4) association of that points belonging previous referenced plan; 
5) fulfilment of remaining intermediate region as responding to the coplanar characteristics of membership. 
The undoubted usefulness and speed in the execution of such process consist in the fact that the surface points do not need 
further elaboration, since belonging to the already referenced surface, and can be simply identified by one photo. The returned 
model is determined, at first, by trending single photograms trough control points; then, trough the referencing of about 1500 
points; finally, trough about 2150 surface points, needed to describe those superficial elements belonging to different layers, 
besides lines and surfaces. 
e) The model identified one from references points, surface points, lines and surfaces provides for an approximation degrees equal 
2%. Since that, it has been further elaborated, relocating points whose range exceed 1%, in order to obtain a final result below 
such value. 
f) The final phase of the graphic elaborations makes use of the model exported in 3dsmax with the surfaces textured, defined 
geometrically by the program, containing the materials that correspond to the textures elaborating by the photographic images. 
On final 3D model, using a software CAD, has been taken some vertical and horizontal (slice/sections) with an approximation 
compatible with the scale 1:20 predetermined. 
The cryptoporticus in the Casa dell’Ancora in Pompeii (G. Spadafora) 
This second test regards the survey and the drawing of the cryptoporticus in the Casa dell’Ancora {Regio VI, Insula 10, n. 7). 
Though the project of photographic shooting and dimensional survey regarded the whole complex, in this paper we present only the 
results concerning the eastern wall. 
The final aim in dimensional accuracy guided the preliminary operations of the test: the construction of the graphic support model, 
the choice of significant points on the object able to allow a quick orientation of each photogram, and the location of the best views 
for the visual yield. The first question was to obtain quickly a schematic three-dimensional model to display the characteristic 
elements of the cryptoporticus, through the immediate perception of the materials and building techniques compatible with a 
representation scale of 1:100. The second question was to have a detail of the general model, telling the plane of the dry wall from 
the plane of the plaster with an approximation compatible with a representation scale of 1:50/l:20. 
To synthesize the description of the operating approach relative to the first question, we list the succession of the different phases 
beginning from the analysis modalities. 
a) The eastern wall of the cryptoporticus in the Casa dell'Ancora shows three different planes: the outer one is shaped by the pillars 
and by the epistyle; the middle one is determined by the arcades; and the interior one ,s determ,ned by the background of the 
roundels. Actually, the detachment of the plaster on large par, of the building surfaces determines other acc,dental ptanes 
However, the survey project was somewhat simplified in order to obtain a three-dtmens.onal model that synthettcally describes 
the general architecture of the garden. , . - , 
b) The above considerations limited the operations on the spot to the construction of a regular graph,c model of support through 
very few measurements. The markers were placed on the pillars to a he.gh, of about ml 1. 0 m correspondence w„h the bricks, 
uncovered by the plaster that is mostly in the lower part. Having in mind this horizontal plane of reference, upper and lower 
elevations of the pillars were measured as if they were on a vertical line. Also the depth ol f the pilllars was measured 
definition of the plans of the arcades lying behind. The project of photographic shoo ing considered the number of plans to draw 
and therefore nrovided at least three photograms for the arcades, two angled and one irontal. 
c) The acquisition of the photographs directly from negatives, by scanner Nikon LS30 and the calibration of the photographic 
device were made in the same way as for the Tombs of via Nocera, described in the previous paragraph. ... . . 
d) The fcZ ng Phase in laboratory concerned the realization of a 3D model in CAD environment, on the basis of the 
o lowing phase, in y, allowed the immediate visualization in Photo 
measurements made on the spot. The export ot the mouei m 
modeler.