出版社：The Society of Photographic Science and Technolgy of Japan
摘要：It is not convenient to use the ordinary sensitometer with 1/20 sec. exposure for photographic materials which are exposed to very low intesity as in the astronomy. A low-intensity sensitometer was designed as Fig. 1 where a low intesity light beam is reflected by a porcelain reflector & passes through a narrow hole to the film. The exposure time of 3-4 hrs. is suitable for the material used.Some photographic materials made by Fuji Photo Film Co., having the similar characters of 103 aO, 103 aD, 103 aF of Eastman Kodak were tried by this low intensity sensitometer. The results showed that this sensitometer is suitable for use of such materials.
