4-12. SOLUTIONS FOR ROLL FILMS
a. Temperature. It is important that the entire processing cycle be carried out at
68F. Above 70F, the emulsion may be softened to such an extent that the edges of
the film are damaged.
b. Exhaustion Limits. The maximum amount of film that may be processed in
each of the processing solutions is as follows:
One gallon of rapid x-ray solution will develop 200 feet of film.
One gallon of acid rinse solution will stop development of about 100 feet
(3) One gallon of fixing solution will fix 300 feet of film. However, this
capacity will be lessened when short lengths of film are processed.
(4) One gallon of wetting solution should be sufficient for 100 feet of film. It
should be discarded after each batch of 100 feet. For optimum results, these
recommended limits should not be exceeded. When the recommended amount of film
has been circulated through one of these solutions, the solution should be discarded.
4-13. PROCEDURES FOR PROCESSING ROLL FILMS
a. Prewetting Roll Films. Unless the film has been wound onto the processing
tank spool under water, it should be wet with water at 68F before being placed in the
developer. This may be done by running the film through the water-filled tank for five
b. Developing Time for Roll Films. It is important that the developing time be
measured from the time of immersion of the film in the developer to the time of
immersion in the rinse bath. The developing time at 68F for the first 100 feet of film in
one gallon of developer solution varies with the length of the roll being processed.
These times are listed in table 4-5. The developing time should be increased by one
minute for the second 100 feet of film processed in one gallon of developer solution.
c. Rinsing Roll Films. The film should be removed from the developer solution
and immersed in the stop bath as rapidly as possible. (To make the stop bath, add
16 ounces of 28-percent acetic acid to water to make one gallon of solution.) To stop
development quickly over the entire length of film, wind the film by hand through two
complete cycles in each direction.
d. Fixing Time for Roll Films. The fixing time for various lengths of roll film is
listed in Table 4-6.