PROBLEMS AND PROGRESS IN AIR PHOTOGRAPHY

A review of progress and the present technical status in air photography. While the pioneering developments were on sound lines, scientific investigation gave a better understanding of fundamentals and paved the way for the advance to present higher standards. Advances in lenses and emulsions are considered and future prospects discussed. It is stressed that attention must be given to image movements of all kinds if potentially higher resolving-power is to be realised in practice. Improvements are seen to be necessary in several directions, e.g. film flattening in the camera, filter glass transmission, processing equipment and film distortion. It is pointed out that while full advantage should continue to be taken of possibilities offered by other technologies, e.g. electronic printing aids, as a recording medium for air survey photography has unique qualities and is unlikely to be replaced.