Analytical Study of Photographic Characteristics based on the Observation of Ultra-thin Cross-section of Emulsion Layer

Abstract

Authors have developed the making technique about the ultra-thin cross-section specimen of photo-graphic emulsion layer for electron-microscopical observation. We consider that this specimen will showthe faithful appearances of optional cross-section of emulsion layer, because of this specimen is so thin (few hundred Å) and stable.
Hence, it is possible to determine the number of silver halide grain or developed silver grain per unit area of emulsion layer based on the microscopical caluculation of grain's number dispersed in the ultra-thin cross-section of emulsion layer. We measured the number of silver halide grain in the undeveloped emulsion layer of Neopan SS Film and the number of developed grain of each six parts of developed layer of the same film along three characteristic curves which were exposed in sensitometer and developed by D-72 (1: 2), ID-68 and DK-20 developers at 20°C: 3 min., 20°C: 10 min. and 20°C: 15 min. respectively, according to above mentioned procedure. These values are shown and discussed in connection with exposure quantity and density.