Storage and display of information in roentgen films

Roentgen images of high density, without actually being overexposed, tend to leave small details of low contrast unrecorded. Still, these details may be reproduced by the same film if the density is lower, even if the gamma value is kept constant. The present report is concerned with how information is stored in the film and the information stored is displayed to the inspecting eye. It appears that films of high density contain information which is invisible, so that the disappearance of image details to a certain extent reflects a defect of display.