adjustable processing hanger is especially designed for processing any length of
35millimeter or 70 millimeter film up to 11 feet. Adjustable film guides accommodate
strips of different widths, while sliding clips on the top and bottom bars hold the film
smooth. The number 11 processing hanger is of the channel type and holds five sheets
of 2-11/16 by 6-1/2-inch film. Other hangers are available for 4 by 5-inch and 4 by 10-
inch films.
b. The processing procedure is the same as for conventional radiographs in
tanks. Green-sensitive films are developed for seven minutes at 68F in rapid x-ray
developer while blue-sensitive films require eight minutes. This difference is caused by
the fact that the films are coated with two entirely different emulsions. In all instances,
an acid rinse bath should be used as a rinse between developing and fixing of the films.
Section III. SPECIAL PROCESSING METHODS
4-15. HIGH TEMPERATURE PROCESSING
If it is not possible to cool the solutions and wash water to 68F, a number of
general precautions may be exercised to lessen the difficulties of processing x-ray film
at higher temperatures. For temperatures up to 75F, the development time should be
shortened as indicated in the development time-temperature table (see Table 4-1). The
fixing solution should be renewed frequently. The film should be fixed for fully 15
minutes to ensure maximum hardening and the washing time should be limited to 15
minutes. A good practice is to use a fixing solution, which is twice the volume of the
developer, and to change the fixer when the developer is changed. Short development,
through fixing, and minimum washing all help to prevent excessive softening and
swelling of the emulsion gelatin.
4-16. TEMPERATURE ABOVE 75F
For processing at temperatures above 75F, further precautions must be taken.
It is not generally possible to work with solutions at temperatures above 95F due to the
likelihood of reticulation and blisters. The recommended processing times for
development, hardening, and fixing of x-ray films are given in Table 4-7. Between
development and fixing, the film should be rinsed in a solution made with the hardening
bath formula. This solution hardens the emulsion.
DEVELOPMENT--RAPID
HARDENING BATH
FIXATION
TEMPERATURE
X-RAY DEVELOPER
80F
1 1/2 minutes
3 minutes
10 minutes
90F
1 1/2 minutes
3 minutes
10 minutes
95F
1 1/2 minutes
3 minutes
10 minutes
Table 4-7. High temperature and processing time.
MD0954
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