AIR PHOTOGRAPHY APPLIED TO SURVEYING

AIR PHOTOGRAPHY APPLIED TO SURVEYING

This book, written by one who is a real authority on his subject, fulfils a long-felt need in bridging the gap between the specialist work and the popular book. It is intended for those who wish to make use of air survey to fulfil their particular purpose as well as for students of the subject.

Engineers, scientists, industrialists, town planners, estate developers and economists-all will realize the vital necessity of adequate air photography to survey standards at a very early stage of economic development of the region, not only to enable the required maps to be prepared without undue delay, but so that photographs are available for scientists and all the others concerned in such developments.

It has been shown that successful surveying from air photographs depends upon full appreciation of the scientific requirements of air photography and of methods of mapping from them. This work gives important information on the pitfalls which may be encountered by the uninitiated.

Before outlining the various methods, elementary perspective and stereoscopy as applied to the subject are given. A description of the simple graphical ‘radial-line’ method of plotting is then given, followed by the corresponding simple method of plotting contours. The basic principles are given of the various types of elaborate plotting machines, together with details of some of the more important ones.

Recent great improvements in photographic materials and technique of photography have resulted in much more accurate results with stereoscopic observations, and instruments such as the stereocomparator have enabled the scope of a simple method to be increased to the 1/2500 scale.