XIII Congress of the 
International Society for Photogrammetry 
Helsinki, 1976 
Commission V 
Invited Paper 
MAURICE CARBONNELL 
Institut Géographique National 
Paris, France 
Technical Progress in 
Architectural Photogrammetry 
Technical progress in architectural photogrammetry during 
the last several years includes the general trend towards 
improvement and better adaptation of equipment, the use of 
all photogrammetric methods, and the expansion of fields of 
application in the sphere of architecture and protection of 
sites. 
EQUIPMENT 
Lie ARE MANY working conditions to be 
considered in architectural photogram- 
metry and, because there is no univeral solu- 
tion, one must accept that a range of equip- 
ment is necessary. It is with this range of 
equipment that photogrammetric instru- 
ments have been involved. We consider 
below the different technical criteria to be 
satisfied and the different solutions adopted 
for each of them. 
VARIOUS PRINCIPAL DISTANCES 
In addition to phototheodolites, which 
have long focal lengths and narrow fields of 
view, many cameras have been produced 
with short principal distances and wide fields 
of view. In this category are the largest 
number of instruments now being produced, 
e.g., all the stereometric cameras (except the 
Officine Galileo Veroplast) and some small 
format individual cameras. 
More recently the necessity for cameras 
with much longer focal lengths (problems of 
accuracy and of distance from the object being 
photographed) has encouraged manufactur- 
ers to build new devices with focal lengths 
intermediate between those of the small 
cameras and those of the phototheodolites, 
the most useful ones still retaining a large 
PHOTOGRAMMETRIC ENGINEERING AND REMOTE SENSING, 
Vol. 41, No. 12, December 1975, pp. 1513-1517 
field of view. During recent years one has 
been able to purchase 
Officine Galileo Verostat: f = 100 mm, 
9 by 12 cm format 
Carl Zeiss TMK-12 
9 by 12 cm format 
Zeiss Jena UMK 
13 by 18 cm format 
Hasselblad MK-70 Planar: f = 100 mm, 
6 by 6 cm format 
Wild P-31 
4 by 5 in. format 
(principal point off center) 
Various Japanese Sokkisha cameras also 
have been produced. 
VARIABLE PRINCIPAL DISTANCES 
It is possible to slightly modify the princi- 
pal distance of some cameras in orderto focus 
at different distances. This facility, which is 
being reexamined by the manufacturers fol- 
lowing recent optical and mechanical ad- 
vances, is based on four different technical 
solutions: (1) displacement of the objective 
lens by a spiral movement (Officine Galileo, 
Hasselblad), (2) displacement by a transla- 
tory movement (Zeiss Jena), (3) introduction 
of rings of different thicknesses between the 
camera chassis and the lens (Wild), and (4) 
introduction of additional lenses in front of 
the objective (Carl Zeiss). 
: f = 120 mm, 
+ f= 100 mm, 
: f = 100 mm, 
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