تظهير الأفلام بواسطة الوعاء ( Tank Developing film ) -٢- كتاب فن التصوير الفوتوغرافي

Endorsement of films by container (Tank Developing film) -2-

Do not start endorsing a film before obtaining that information about the appearance and the film. The time required for endorsement ranges between two or three minutes and half an hour

When you know the exact developer time, quickly and gently pour the developer into the bowl (picture 3). For accuracy, record the time since the beginning of pouring the solution, and if you are using a timer (a clock for timing), press its button when you start pouring the solution completely.
Since the endorsement time is calculated from the start of pouring until the moment it is removed from the container, you must pour it as quickly as possible, provided that you do not stop pouring before the container is full, but be careful not to overflow the container because the solution leaves permanent stains on the places where it falls. The best way to avoid this is to prepare an amount of solution exactly enough to fill the container shown.

Shake the display in the bowl every 30 seconds. The proper way to shake the appearance varies according to the type of vessel; Some of them have a tight-fitting lid so that the liquid does not leak out, and in this case you have to turn the container upside down. Others have a metal rod that can be inserted into the upper end of the container and connected to the inner wheel, which enables this wheel and the film wrapped on it to be rotated. In this type, move the wheel for five seconds every half a minute (picture 4)

Warning: the error in stirring the presenting solution results in a distorted and incompletely developed negative crystal.

When the timer bell rings announcing the end of the endorsement period, or when the time that you wrote down as the endorsement period expires, empty the content of the endorsed container and quickly fill the container with plain water. Most of the clear solutions remain usable for several weeks or several months if kept in a cool place, so keep the solution in a dusty, dark-colored bottle (Amber Bottle) with a tight-fitting lid, and follow the instructions accompanying the solution to use it again.

Ensure that the display container is filled upright with plain water after emptying it of the display material. Shake the bowl for 20 or 30 seconds, then remove the water from it. This process washes most of the film-expressing material and thus prolongs the life of the fixer solution, which will be used in the next step.

Fixation time is also important, and it varies according to the type of fixing solution. The normal slow solution takes ten minutes if it is fresh, while only two to four minutes are required for the fast fixer. Without the necessary time, then pour the fixing solution in
The bowl. Stirring of the stabilizer is necessary only in the first half minute or so.

During the stabilization process, the unexposed silver bromide granules are washed and expelled, and the parts that have not been exposed to light become transparent. If you are not sure of the required fixation period, you can examine the film in white light a minute after dipping it in the fixative, by removing it from the container and examining the fixation percentage. Examine it several times to determine when the unexposed parts become transparent. This process requires leaving it in the solution twice as long as it takes for this to happen.

When you are done fixing, empty the fixative from the container into a vial and store it for later use. Wash the film in running water for 20 minutes. The simplest way to do this is to insert a water tube into the container, and open it with enough force to ensure the flow of water (Fig. 5). If the used container does not have a special hole, then put the roll with the film in the container and run it under running water for 30 minutes. You can also remove the film from the reel and wash it in the kitchen sink (sink) or in a large bowl.
The film was hung in a clean, dry place, and it was weighted from the bottom with metal clips to prevent it from swinging and turning during the drying process. Moisten a piece of chamois for photos, or a piece of cotton with water, then squeeze it well and gently wipe the two sides of the film to remove the stuck water. Be careful not to scratch the film or leave water spots on it, because when it dries, it leaves a mark that appears in the print.
The specialized companies have recently produced a special substance (Photo Flow), which if added to the water for the last wash, is used before the water slides off and the film dries quickly.

The time required for drying is important, and the best results can be obtained if the film is allowed to dry from half an hour to an hour, and the maximum is two hours. But if the drying process is accelerated by using heat, then this spoils the film and increases the granules. But if the film is left to dry in a humid atmosphere for a long time, this will spoil its sensitive layer. For 35 mm films, half the time required for other films is required.

Waiting for the film to dry, clean the used tools, because all kinds of solvents that appear and fixatives leave deposits that are not removed by washing alone, but must be wiped and the containers carefully dried.