What is the function of fixing the film after developing?

The function of fixing the film after developing is primarily to remove the affected silver salts. During the developing process, the film undergoes a chemical reaction where exposed silver halide crystals are converted into black metallic silver, creating the image. However, unexposed silver halide crystals remain on the film even after development. The fixing solution plays a critical role by dissolving and removing these unexposed crystals. This ensures that the image becomes stable and will not change or develop further when exposed to light or additional chemicals.

This step is essential for achieving a permanent image on the film, as it prevents fogging or discoloration that might occur if the unexposed crystals were left on the film. The proper fixation process contributes to the longevity and clarity of the final radiograph, making it an integral part of radiographic processing.