LENGTH OF FILM
DEVELOPMENT AT 68F
6-1/2 feet
6 minutes
25 feet
8-1/2 minutes
50 feet
9 minutes
100 feet
10 minutes
Table 4-5. Developing time--roll film.
LENGTH OF FILM
FIXING TIME AT 68F
First 100 feet
10 minutes
Second 100 feet
12-1/2 minutes
Third 100 feet
15 minutes
Table 4-6. Fixing time--roll film.
e. Washing Roll Films. To increase the flow of water through the motor-driven
tank during the washing procedure, one end of the cover assembly should be propped
up about one-quarter inch. The hose nozzle is inserted into the bottom of the solution
trap and the film should be washed for at least 25 minutes in rapidly running water.
f. Preventing Water Spots. Following washing, the flow of water should be
stopped and the motor turned off. The lid of the tank with the film pools attached should
be removed and about a pint of water poured from the tank. Then, 1-1/4 ounce of
wetting solution should be added to the remaining water. The lid and spools are
replaced and the motor runs for five minutes.
g. Drying Roll Films. All photofluorographic film requires great care in drying.
Drying should be done in a room as free as possible from dust. After film has been
removed from the tank, excess water should be removed with a chamois, photographic
sponge, or squeegee. This should be done regardless of whether the film is to be dried
in loops or on a rack. If heat is used, the film should never be allowed to become bone
dry since it will tend to become brittle. Allowing the film to remain several hours in a
normal room atmosphere after drying will promote equilibrium between the moisture
content of the film and that of the room. When the film is dry, any residual spots or
fingerprints may be removed with film cleaner.
4-14. PROCESSING SHEET FILM AND SHORT LENGTHS OF ROLL FILM
a. Standard tanks for processing 14 by 17-inch radiographs may be used to
process both sheet and short lengths of 35 millimeter and 70 millimeter roll film. An
MD0954
4-11