Luminance Measurement by Photographic Photometry

In the field of illuminating engineering, a great deal of time and effort is currently being devoted to the subject of luminance design. Throughout such considerations, problems frequently arise with respect to the actual determination of the luminance values themselves. For this purpose several methods can be used. It is probably true that all these methods have, to a greater or lesser extent, disadvantages associated with their use, due largely to the complex nature of the quantity to be measured. This paper is a summary of a system of luminance measurement which relies on the photosensitive reaction of photographic film. The authors feel that the technique has certain advantages of other methods, and is worthy of consideration.