Abstract
The progress of science has accelerated the automanization in every field : As for the X-ray photography, the developer, the chemicals of which are previously fixed together, has heen used. In order to study the relation between the developer and the density, or the fog of film, the authors made fundamental experiments, using several kinds of developer. The developing time, one of the important conditions of developing, was examined throughly and the time of 4.5 minutes at 20℃ was used. From the experiments, the following were concluded : 1) As for the film made in Japan, the develper has hardly effects on the density. 2) As to the EK film, the sensibility of film is possible to be cahnged as the result of the change of the developer. Besides, the results of the experiments by using grid was reported here.
