Dd 
Some Considerations on the Application of 
Photogrammetry for Small Scale Cartography 
The further development of Wild equipment, Part III 
by H. Kasper, Heerbrugg 
Summary 
Original mapping at small scales of large unsurveyed areas can only be carried out by the photo- 
grammetric method if the results are to be an improvement on those obtained from route survey, 
ground survey, etc. Nevertheless, there was until recently no really satisfactory photographic and 
plotting equipment for application of the photogrammetric method for this particular problem. In two 
papers published in Photogrammetria, the author has already reported on this subject and on the 
development of the necessary instruments. 
The range of Wild instruments for small-scale cartography - consisting of the RC9 Aerial Camera 
with super wide angle lens, statoscope and horizon camera, a diapositive printer embodying electro- 
nic dodging, the A9 Wide Angle Autograph with electric coordinate printer, and the Stereocompara- 
tor, also with coordinate printer - has been completed by the addition of two new small-scale plotters. 
This closing paper on small-scale cartography describes how these instruments are used in practice 
in the economical production of small-scale maps of large areas. Model and analytical aerotriangula- 
tion are discussed and compared. 
The principal feature of the whole method is its versatility of application and the strict geometrical 
solution of the plotting instruments. 
Introduction 
In two papers which have appeared under the same title in Photogrammetria XII, 1955/56 No. 1 and 4, 
some observations have been presented on the question of the instrumentation necessary to solve, 
by photogrammetric means, the most important problems in original small scale cartography of the 
order of 1:50000 and 1:100000. After comparison of the various possibilities, the conclusion was 
reached, insofar as the construction principles are concerned, that the answer lies in the use of 
vertical photography using a super wide anglelens. 
In this, the third paper, a description is given of all the instruments which have been developed in 
Heerbrugg since 1954 in fulfilment of these considerations. It will also be indicated how the applica- 
tion of the new range of instruments is foreseen in practice. 
Once again mention is made of the requirements to be expected of survey methods in the future in 
connection with the preparation of small scale maps. The urgency of opening up, in an economic 
way, large areas in the developing countries, where up to now suitable cartographic material was 
lacking, demands fulfilment of the following conditions: 
1. The maps for the economic planning must be available as quickly as possible. 
2. The cost of preparation must be kept low. 
3. The accuracy of the maps must nevertheless be so high that they serve not only for the immediate 
requirements of first development, but also for the later higher demands of general technical 
planning; and furthermore revision by simple methods should be possible. 
As has been shown in the two previous papers, the analysis of the economy and suitability of the 
photographic technique has led to the basic conception that for an optimum photographic lens, a 
super wide angle lens with a 120° angular field, for 9” x 9” negative size, is indicated. The area to 
be surveyed is to be covered fully by vertical photography in strips. The construction of a high- 
performance super wide angle lens was therefore the most important condition for the development 
of the whole range of instruments. This problem was solved by L. Bertele's calculation of the Super- 
Co