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The manufacturer’s recommendation should be followed in choosing a development time. Longer development time generally yields faster film speed and slightly more contrast. Development-Normal development is 5 to 8 min at 68☏ (20☌).(12.7 mm) and agitate in two directions for about 15s. Separate to a minimum distance of 1⁄2 in. Start of Development-Start the timer and place the films into the developer tank.Hangers are loaded and solutions stirred before starting development. Preparation-No more film should be processed than can be accommodated with a minimum separation of 1⁄2 in.To reduce drying time and prevent watermarks, a wetting agent is used. If the film is dried in this condition, not only will the drying time be extended but watermarks will be left on the radiograph. After the wash step, water adheres to the film in streaks and drops. Wetting Agent When the washed film is dried the processing is completed.

Buffer - (equivalent to Kodalk mild alkali), etc.].The fixer contains a solvent for silver halide and other ingredients, as shown below.įixer-Silver Halide Solvent. Almost all fixers in common use are of this acid hardening type. Acid hardening baths that stop the action of the developer carried with the film and harden the emulsion are used in all fields of photography, let alone radiography. The emulsion which is softened by the developer is hardened by the fixer. These chemicals possess activity that converts silver halides to soluble compounds. Ammonium thiosulfate is also used when quick fixation is required. The commonest fixing baths are solutions of sodium thiosulfate. The fixer is used to remove the unreduced silver halide. Such material is detrimental, especially to the radiograph as viewed by transmitted light. If the stop bath is not used, the developer carried over with the film not only increases the exhaustion of the fixer but may become the cause of a lack of processing uniformity or stain formation in the radiograph FixerĪfter development and stop bath neutralization the emulsion still contains unreduced silver halide which is not necessary for the image. In radiography, a 3% solution of acetic acid is used. To stop the action of the developer and prevent uneven fixation, a 1.5 to 3% solution of acetic acid is used as the stop bath.

If the film is directly transferred from the developer into the fixer, uneven fixation is liable to occur. The silver image becomes too dense to serve the intended purpose unless the action of the developer is stopped at a proper time.