What is the primary function of the fixer in the radiography process?

In the radiography process, the primary function of the fixer is to remove unexposed silver halide crystals from the film. After the film has been exposed to radiation and developed, it contains both developed silver (which forms the image) and unexposed silver halide crystals. The fixer, which is a chemical solution, works to dissolve these unexposed crystals, preventing them from continuing to react to light and ensuring that the image remains stable and does not change when it is exposed to light during handling or viewing.

This process is crucial because it ensures that the final radiographic image is clear and permanent. If the unexposed crystals are not removed, they could darken over time or cause fogging on the film, which would ultimately compromise image quality. Therefore, the role of the fixer is essential in achieving a high-quality radiographic image.