CI PA 2003 XIX 11 ' International Symposium, 30 September - 04 October, 2003, Antalya, Turkey
504
A: Kind of point, 1 theodolite station
2 -> premarked control point
3 -> detail control point
4 -> section point
BC: Code number of crossection
DEF: serial number of point
3. DATA PROCESSING
3.1 Calculations
During the time following each monthly campaign all collected
data were suitably processed. All calculations not executed in
situ were completed at home in order to enable the survey work.
All measured points were determined in a common geodetic
reference system. The X-axis of the system was determined by
two points on the long axis of the Greek Orthodox Katholikon
within the monument complex. The south entrance of the
Church was given the height of 754m above sea level, using a
nearby vertical reference point. In this way all external
influences on the determination accuracy of the points was
excluded.
All survey stations and the control points of the first campaign
were adjusted in a common network. However, this was
considered unnecessaary thereafter as the geodetic
measurements ensured the required accuracy for the survey
stations.
It is estimated that the accuracy achieved for the survey stations
was of the order of 5mm, for the premarked control points of
the order of 8 mm, of the other detail points about 12mm.
3.2 Survey and Photogrammetric Work
The basic section lines for each crossection were plotted within
the AutoCAD environment. Initially version 10 of the software
was used, while for the last campaign, i.e. seven years later
version 2000!! For the correct projection of the points a 3D
rotation was considered necessary. For this purpose special
software was developed, in order to perform this rotation.
It was also established that most photogrammetric software
refuses to perform the adjustment of a stereopair if the reference
system of the control points does not simulate the situation of
the aerial photography. This means that the reference system
should have the Z axis pointing towards the camera.
All photogrammetric stereopairs were oriented and plotted
either on a Leica DVP digital stereoplotter, or an Adam MPS-2
analytical stereoplotter. The three dimensional photo
grammetric outputs were later processed by the team of
architects, in order to produce the final drawings (Figure 3).
SVT
Figure 3: A sample of the vertical crossections - South facade
An interesting project was the compilation of the drawing of the
roof tops. As aerial photography over the Old City Jerusalem
was prohibited, the plan was compiled by suitably adjusting
photogrammetric measurements from several 35mm colour
slides taken with an amateur camera and a zoom lens with
unknown geometry (Georgopoulos and Modatsos, 2002)
(Figure 4).
Figure 4: Rooftop plan
A total of 35 drawings were produced. Included are the four
plots of the plan drawing. All these plans cover an area of
40000 square metres approximately at the scale of 1:50.
4. CONCLUDING REMARKS
This unique project can never end. The complexity of a
monument such as the Church of the Holy Sepulchre, does not
present an easy task, when its documentation is concerned.
Moreover the fact that it is a living monument presents even
more difficulties. All religious communities active within its
walls and the endless crowds of pilgrims who visit the Church
every day all year round present even more obstacles, which
can never be overcome or set aside. One should work with
respect to the place and the people active in it.
However this project has been an excellent example of co
operation. On one hand, there is interdisciplinary co-operation.
Surveyors, Architects, Photographers, Archaeologists and
Photogrammetrists worked harmoniously for a really long time
under adverse conditions to complete the difficult task. On the
other hand there is interreligious co-operation. Greek Orthodox,
