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The photogrammetric method becomes even more economical when 
complicated accidents have to be recorded. Measuring an accident 
with a tape measures is far more time-consuming than taking a 
photograph, especially bearing in mind that as a rule a number 
of important detail must be recorded, possibly under extreme 
climatic conditions. A major factor contributing to the great 
economy of photogrammetry is the accuracy of the measurement. 
Various comparative measurements between conventional and photo 
grammetric procedures have confirmed the theoretical premises. 
The capital investment cost in equipment for a single photogram 
metric office is distributed as follows: 
1 Wild A 40 Autograph 45 % 
4 Wild C 120 Stereometric Cameras 45 % 
1 Wild C 40 Stereometric Camera 10 % 
The plotting and elaboration of the plans is carried out in one 
or more centrally located plotting centres, depending on the size 
of the territory to be served. The ratio of stereometric cameras 
to autographs may vary from 4:1 to 6:1, depending on the size of 
the area and the frequency of accidents. As a rule, the instruments 
can be amortised within ten years. With the equipment described above, 
it is possible each year to carry out the following work: 
Preparation of 1000 plans 70 % 
Preparation of approx. 2200 photo 
graphs including enlargement 22 % 
Filing of approx. 650 photographs 
which may be significant at a later 
date v 8 % 
The financial burden is quite modest in comparison with the other 
costs occasioned by a traffic accident or a crime and is hardly 
of any consequence. Any surplus after the ten years' amortisation 
reverts to the state. 
How do other users of photogrammetry equipment benefit financially 
from this method? Photogrammetry provides reliable documentary evi 
dence for architectur, conservation of monuments, archaeologists 
and engineers. Measurements can be carried out in a very short time 
and they are both cheaper and more accurace than measurements taken 
with conventional methods. The economic advantages of the photo 
grammetric procedure can be outlined by means of a practical example. 
On the occasion of the "European Year for the Conservation of Monu 
ments", the authorities of the Canton of St. Gallen in Switzerland 
commissioned a photogrammetric survey of the "Old Museum" in St. 
Gall eh. The photography was done with the Wild P 31 Universal Terre 
strial Camera, f = 10 cm, while the plotting was done on the Wild 
A 10 Autograph. The time taken for this project can serve as a stan 
dard for photography and plotting of other projects. The following 
brief technical description will give you an idea of the extent of 
the task.