4-9.
CHEMICALS FOR PHOTOFLUOROGRAPHIC FILM PROCESSING
Processing chemicals recommended for use with photofluorographic films are
rapid x-ray developer and acid rinse bath, x-ray fixing solution, and wetting solution.
Regular x-ray developer should not be used because of its relatively lower development
activity. Solutions prepared for these chemicals may be stored in bottles prior to use.
All used but unexhausted solutions should be stored in stopper bottles also.
4-10. PROCESSING ROLL FILM
a. In processing roll film, the leader and trailer should not be left attached to the
ends of the roll while it is being processed. There are camera-activating perforations
along the edges of the leader and the trailer. If the film is rolled on spools in the tank so
that the first and last few frames will be in contact with the leader and trailer, the
perforations can be the source of oval areas of increased density on these frames. The
alternative to removing the leader and trailer prior to processing is not to make
exposures on the first and last three of four frames on a roll.
b. In transferring the film from the magazine of the camera to the spool of the
tank, great care must be exercised not to produce crimp marks or abrasions on the film.
In addition, static electricity will occasionally be created during this operation if the
humidity is low. This can lead to the creation of tree-like artifacts on the film. This can
be prevented if the magazine itself is placed temporarily on one of the spindles of the
tank cover assembly and the film threaded and started onto the processing spool. The
entire assembly can then be immersed in water and the transfer of the film to the spool
completed. The empty magazine reel is then removed and the other processing spool
put into place.
4-11. PROCESSING FACILITIES FOR ROLL FILMS
a. A shallow sink, 30 inches long by 20 inches wide by 12 inches deep,
equipped with a standpipe is very useful as a water jacket. The processing tank as well
as the solution bottles can be placed in the sink for regulation of the temperature. The
sink should be supplied with both hot and cold water and either a mixing faucet or a
thermostatic mixing valve, the latter being the more satisfactory. A rubber hose
connected to the faucet or the valve outlet is useful for filling or cleaning the processing
tank and solution bottles as well as for filling the sink itself.
b. The motor-driven, rewind type tanks are designed with a spout so that if
necessary only, one tank can be used and the processing solutions poured in and out
as necessary. However, it is much more convenient to use two tanks so that the motor-
driven reel assembly can be removed from one solution and immersed in the next
solution in a second tank with a minimum loss of time.
MD0954
4-9