Abstract
The X-ray chest radiography is most frequent used in all X-ray radiography, however, it happened many times that problems are raised at a case of diagnosis for the season of becoming degraded into habit from the monotonous of the work. This report contained the present condition of chest radiography in our land, its problems and opinions, furthermore practical geometrical subjects, emulsion, granular quality, contrast media, scatter radiation, the system of exposing value controlled. Thus, there have been so many problems on chest radiography and also it is recognized that gap is found between the theory and practice, particularly the problems of : wave form on secondary switched 3 phase 12 pulse system, of photo timer, of divided measurement method of light value on the exposing value controlled system and of saving the exposing value with quality of radigraphy depended on each type of equipment, then its explication of these problems and study by the comparative method. Especially for saving the exposing value, the problems happened between less exposing value and quality of radiography are against each other, so actually considering the exposed value, the diagnosis should be given prority, particularly on chest radiography it should be planned to make further progress of technology and quality of radiography.
