PHOTOGRAPHIC SURVEYING OF 
   
   
  
   
HISTORIC BUILDINGS 
SUMMARY: 
Photographic surveying of the historic buildings has been 
carried out systematically in Belgium these two last years. The 
country is thus materializing the wish Dolezal expressed during 
the Iyf^ Congress on Photogrammetry held in Paris. The underta- 
king is patronized by the "Corps de Sécurité Civile” responsible 
For the preservation of the artistic inheritance of the Nation. 
The technical execution is entrusted to the "Service de Topogra- 
phie et de Photogrammétrie du Ministère des Travaux Publics", who 
in turn have taken the advice of experts in archeology and art 
history and of the "Commission Royale des Monuments et des Sites". 
The result aimed at is not an immediate drawing up of the 
maps of the existing buildings, but the gathering of photographic 
documents accompanied by the essential metric elements from which 
building maps may be arawn up, at any time. 
The plotting material - 155. order blotting instruments of 
the universal type - will always be available; it is perfectly 
adapted to the needs of the architectural photogrammetry. Such 
is however not the case with the equipment for taking photopraths. 
Consequently an equipment specially suitable for the task underta- 
hen has been created and perfected by "Officine Galileo” Florence, 
under technical control of M. E.Santoni. 
This equipment consisus of two metric cameras which can 
be adapted to a theodolite. In this way it 1s possible to use 
them as two independent bphototheodolites. Furthermore, fixed 
bases of 2 and 3 m. have been provided for on which these came- 
ras-may be fixed; they can thus be used Like the twin cameras 
known in short distance photoprammetry. Mounted on a fixed ba- 
Se, they can be fitted on a fixed stand or used in ” floating " 
position, owing to the extremely thorough synchronisation of 
the shutters. 
The authors are drawing attention to the difficulties met 
with regard the photogrammetric technioue, but more specially 
from the archeological point of view where they necessarily must 
have recourse to the knowledge and advice of specialists. They 
show the technique and processes adopted for a promp carrying 
out of the task undertaken and the most suitable filing of the 
collected. 
  
documents