A simple model of X-ray photographic action

A simple mathematical model is proposed for the interpretation of densitometric data read on photographic films of various kinds in the energy range in which the effects of photoelectric absorption prevail. The limits of the model and their causes are discussed; these limits are attributed to the use of X-radiation with a wide energy spectrum. It is pointed out, however, that for low energies, where the energy spectrum of the incident radiation is necessarily narrow and the photo-electric absorption is prevailing, the model explains very precisely the experimental data. Some functions are proposed for the calculation of the mass absorption coefficients that are drawn from the interpolation of experimental data