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installation time

The time required to fix the film is very important. If that period is prolonged, it dissolves some of the silver that forms the image and weakens the light areas in it where the details are important, just as prolonging the setting period prolongs the time required to wash the printed image. But if the installation period is shorter than what is necessary. The crystal and the printed image are stained, and their colors fade with time.

The fixation process is divided into two phases: in the first half of the process, silver bromide is converted into a colorless compound, but it is slowly soluble, and in the second half, this compound is transformed into another compound that dissolves quickly. For this reason the time required to set should be twice the time required to render the crystal colorless or light.

If the fixing solution is fresh; It whitens the film within five minutes, and fixes it within ten minutes. The older it becomes, the slower its effectiveness decreases, and it must be thrown away when the time required for whitening becomes 8 minutes and fixation is 16 minutes.
As for the fast-acting solutions, they fix the film by two or three minutes if they are used without diluting their strength.

Film washing

After the endorsement process, the gelatin of the sensitive layer is loaded with chemicals that continue in its effect unless it is stopped by washing to make the image permanent. Washing the film with fast running water at a temperature between 15°C and 21°C is sufficient. But if the water temperature is less than 15 degrees Celsius, and the roll of film is tightly tightened around the wheel, which reduces the flow of water around it, then the time should be increased to half an hour.

Film drying

The film should be dried in a dust free room. Successful drying is the removal of water from the film on a regular basis until its moisture becomes equivalent to air humidity. As for drying the film with a strong, hot air stream, this is a bad method, because this method increases the density of the crystal and makes it wrinkle during the summer when the weather is hot, the solution is warm, and the crystal is full of water. The drying time should not be less than half an hour, and this period is less during the winter, especially if the used film is 35 mm, which generally dries quickly.
If you want to speed up the drying process, you can use a fan to move the air, provided that it does not stir up dust. You can also speed up the drying process
More by using a stream of hot air, provided that its temperature does not exceed 38 ° C.

Wetting Agent

Photographers frequently use a wetting agent at the end of the film washing process before hanging it for drying. The water containing a wetting agent does not collect on the film in the form of dots, but rather spreads in an orderly manner over its entire page, and the water dots do not leave spots on it that appear during the printing process.