I would have expected the film to be completely blackened, once brought to proximity of a strong source of gamma radiation. (i.e. the "Most Dangerous Radioactiv

I would have expected the film to be completely blackened, once brought to proximity of a strong source of gamma radiation. (i.e. the "Most Dangerous Radioactive Material") Even if the camera was put into lead encasing, the shielding shutter was opened for quite a long time and pointed directly at the source of the gamma rays.