182
Maestri, Canciani, Spadafora
max
min
avg
PHOTO
48
POINTS PER PHOTO
8
28
18
TOTAL POINTS
502
PHOTO COVERAGE (%area)
23
80
50
CONTROL POINTS
169
FIDUCIALS PER PHOTO (%)
n/a
n/a
n/a
REGULAR POINTS
4
SURFACE POINTS
329
RAYS PER 3D POINT
1
6
4
POINTS ON ONE
PHOTO ONLY
number
%
ANGLE INTERSECTION
0
89
63
0
0
RAY TIGHTNESS (% of size)
0
2
0
POINTS ON TWO
PHOTOS ONLY
2
1
APPROXIMATION MAX
0.488
Fig. 12: Summary table of the survey data relating to east façade Fig. 13: Viewpoints of the photographic shooting
of cryptoporticus in the Casa dell’Ancora
Fig. 14: Indication of the rectangular support surface Fig. 15: Indication of the surfaces of the arcades
and of the surface points and some surface points
This software required the orientation of the photograms on the basis of the 3D points detectable on the photographs thanks to
the coloured markers. The final model is given up by 181 lines, 169 control points and 329 surface points. The plane of each
arcade was built subtracting it by a rectangular support surface, referenced with 4 control points shot in 2 photograms at least.
The curve of the arcade was traced on the support surface, through a set of surface points (points belonging to the surface that do
not need the reference process). Subsequently, the arcade defined by the perimeter of the control and surface points was built.
The rectangular support surface was afterwards erased in the 3D modeller software 3DS Max 3.1, used for the final rendering of
the images.
e) The model was several times elaborated in order to reduce the admissible deviation at a level lower than 2% through the hand
correction of the data resulting with a not acceptable approximation. The schematic settings of the model produce an error of
about 5 cm on the entire size, that is acceptable in consideration of the preliminary statements.
f) Then the base model was enriched with further details through the use of photographs so as to become measurable in every part.
For instance, we can measure the bricks or the stones directly in 3D model. A subsequent elaboration with a specific rendering
software (in this case 3DS Max 3.1) allowed to obtain a set of images such as the façade in orthogonal projection.
Fig. 16: East façade detail. Elaboration trough more accurate graphic model