WILD AVIOPHOT RC10A 
THE OPTIMUM CAMERA FOR AERIAL 
PHOTOGRAPHY AND ITS REALISATION 
R. Waibel 
Wild Heerbrugg Ltd 
Heerbrugg, Switzerland 
SYNOPSIS 
Only a reliable camera with high-performance objectives can meet the increasingly high quality demanded 
of aerial photographs. In addition, it is important to relieve the operator by far-reaching 
automation of routine functions. Only the use of microcomputers in a multiprocessor system makes it 
possible to translate an optimum concept for an aerial camera into fact. The features of the RC 10A 
are described and explained in detail by the example of two novel functions. A description is included 
of an automatic control system for certain selected camera functions, an information system to maintain 
preselected parameters for an aerial-survey flight, together with the built-in service aids which 
provide the operator with a rapid diagnosis even during flight. 
1. REQUIREMENTS MADE OF AN OPTIMUM AERIAL CAMERA 
  
  
The characteristics which between them constitute an 'ideal' aerial camera will vary according to the 
task to be accomplished. Thus, instead of calling for an ideal camera for aerial photography, it is 
more realistic to think in terms of an optimum solution to the problem. In accordance with the various 
aims and objectives, characteristics can then be deduced which, duly weighted and added together, will 
then result in an optimum camera. The following points form part of these main characteristics: 
1. Picture quality 
2. Reliability of the system 
3. Handling of the system 
4. Flexibility of the system 
5. Price/performance ratio 
6. Service and maintenance 
The requirement for aerial photographs of high quality can be met only by an objective-lens system 
which provides high performance in every respect. 
The most important parameters are the geometrical accuracy of the image and high resolution. In 
addition, image motion also has a substantial influence on picture quality. The predetermination 
of a defined amount of image motion and its-control must thus be possible in such an optimum camera. 
But in addition to the quality of the image itself, the correct exposure of the film is also of : Sue 
importance. ; 
An aerial camera is required to produce an image of-the terrain covered by the flight with the 
required longitudinal and side overlap. An optimum camera must provide the requisite possibilities 
for setting and control for this purpose. - In addition to the analog detection of the apparent ground 
speed, a digital intervallometer with automatic averaging of the time intervals measured is also 
necessary in the case of very disturbed flights and long time intervals. It must provide the 
possibility to control the exposure cycle in such a way that the exposures will overlap by a 
preselected amount (percentage), but-increased-attention must-also be given to providing warnings 
of faulty manipulations and help for-the best possible use of the various camera functions. .The mm 
operator must be relieved of work which can be automated, such as the automatic identification of the 
objective lens in use and central control for setting the film speeds for all phases of the process 
involved in producing an éxposure. Particular attention has to be paid to the reliability of the 
complete camera system. An aerial camera suitable for practical work must be immune to breakdowns 
of every kind. Major influences of this kind include: temperature, humidity, vibration, ageing. 
New camera systems have to be particularly protected from high-frequency and low-frequency interference 
fields and against breakdowns in the power supply. As far as possible, the disadvantages of analog 
components such as drift, temperature dependence and ageing should be overcome by using digital 
systems. On account of their liability to breakdown, sequential circuits should be placed in the 
camera by combined-logic circuitry. The use of a microprocessor at first sight gives rise to the 
suspicion that the program will be run sequentially, with all its usual disadvantages, but a monitor 
control circuit is provided to correct any irregularities. In addition to: the known improvement in 
reliability due to a greater degree of integration, special measures are-also to be required, such as 
the use of temperature-specified modules, a reduction of self-heating, speed reduction of the systems 
and a general burn-in. 
Handling of the camera is influenced considerably by the weight of the optical systems. Optical 
systems always require stable types of construction which are therefore relatively heavy despite 
the use of light materials. By selectively breaking down the camera systems into individual 
components, the requirements of stability of the optical system and good handling characteristics 
can be met. 
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