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The operative procedure gives the possibility to obtain 
horizontal and vertical sections from the model in order 
to verify possible shifts from the vertical. 
Once we realized the model the operator chooses the 
lines defining the geometry of the object to be 
represented, and it is always better if the operator works, 
as far as possible, with specialists who will use the 
resulting elaborates in the following study phases. 
Regarding the south prospect (fig. 5) we decided instead, 
to apply to a simplified restitution method. In restitution 
phase we specifically empoyed the Eclovision system, 
while the photogramms work took place with a Rollei 
6006 semimetric camera. 
The devices carried out in the photogramms taking phase 
suited the small film size (6x6 cm), the photosensible 
material chosen (Kodakcolor Professional 120 ASA film 
and ILFORD FP4 100 ASAQ black and white film), the 
camera setting during the photogramms taking (the 
direction while taking the photogramms has to be 
perpendicular to the object plane); the framing (that is to 
say the ratio between formation of the photogramms 
taking and the average camera-object distance that has to 
be about 1:3). 
A correct planning in taking the photogramms was 
necessary also to the wideness of the south façade, so that 
more models had to be linked together. 
In the restitution phase, the Elcovision system uses a 
couple of positive photogrammms rightly enlarged (in 
our case the employed size was 24x24 cm") and placed 
on a digimetre. 
It is necessary to remark that among the advantages this 
procedure presents compared to the classic 
photogrammetry. the taking photogramms position can 
be. generally, fitted to the environmental nature, besides 
the corresponding points on the two photogrammes have 
to be monoscopicallv digitalised by using the graphic 
bar mouse, in order to make also possible for the not so 
skilled operators the instrumental coordinates knowledge. 
Once obtained, the data enter an orientation program that 
rcconstrunumerical model of the object we want to 
represent. 
The outstanding Elcovis system features are the 
utilisation of the only monoscopic vision and the 
impossibility' to restitute by continuous lines (the 
restitution only by points is something possible). This 
means the necessity of a correct individuation of the 
corresponding points on the two prints, that makes 
impossible for example the restitution of points belonging 
to curves surfaces or placed in non favourable conditions, 
that is in the shade or outside one of the two images. 
The system makes a three-dimensional restitution 
possible, that is the continuous acquirement of the 
coordinates couples and the object lines representation on 
the video. 
Such an operation is supported by a CAD inside the 
program that gives the chance to represent the digitalised 
points at the average image scale and to relate them in a 
si utable way. 
It is possible to choose the ortographic projection plan of 
the representation, keeping in mind the three-dimensional 
coordinates of the resulted points. 
In an experimental way we traced some vertical and 
horizontal sections connected to the south façade, having 
before chosen the representation ortographic projection 
plan (fig. 5) 
Fig. 5 - The south prospect of the church 
The obtained precision, also verified by the comparison 
with the coordinates values of the detailed points, has 
resulted between the graphic tolerance values for what it 
concerns the prospects restitution. 
We noticed a bigger indétermination for the Y 
coordinates (depth) values definition. These values 
differences has in fact been calculated in 5 cm. We are 
obliged to apply to classic photogrammetry for what it 
concerns the projection determination and the shifts from 
the vertical. 
The archaeological survey 
The topographic and photogrammetric survey of the 
ancient Kastro of Pereia represents the second experience 
and in this case the application is in the archeological 
field, (fig. 6) 
The whole work was performed few years ago with two 
different survey's campaigns carried out in Greece and 
more precisely in Tessaiia region. 
Fig. 6 - The ancient Kastro of Pereia