What are the main purposes of the fixing solution in processing radiographs?

The main purposes of the fixing solution in processing radiographs are to harden the emulsion and remove undeveloped silver halide salts. When film is exposed to light or radiation, certain areas of the emulsion become developed, while others remain undeveloped. The fixing solution plays a crucial role in making the image permanent by ensuring that only the developed areas remain visible.

By hardening the emulsion, the fixing solution stabilizes the structure of the image, making it less prone to damage during subsequent handling and processing. Additionally, it effectively removes any undeveloped silver halide crystals from the film, preventing fogging and ensuring that the final image is clear and free from unwanted artifacts. This is essential for achieving high-quality radiographic images that can be accurately interpreted.

Overall, the fixing solution is vital for the preservation and clarity of the final radiograph, fulfilling both the requirements of hardening the image and eliminating any unexposed material which could compromise the resultant quality of the film.