How is film density influenced by exposure time in radiography?

Longer exposure times in radiography generally result in greater film density due to the increased amount of gamma radiation that reaches the film. When the film is exposed to radiation, the intensity of the exposure causes chemical changes in the film emulsion, which results in the formation of a latent image. This process is directly related to the duration of the exposure; the more time the film is exposed to the radiation, the more photons strike the film, leading to a greater accumulation of the latent image.

In turn, this accumulation manifests as increased film density upon development, which is perceived as a darker image on the film. The longer the film is exposed, the more radiation it absorbs, thus creating a denser image that can provide clearer details of the inspected materials or structures.

Shorter exposure times typically result in less radiation reaching the film, which can lead to lighter film density and potentially underexposed images that may not reveal adequate detail. Therefore, understanding the relationship between exposure time and film density is crucial for obtaining high-quality results in industrial radiography processes.