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Figure 10-13.–Sheet film tank processing agitation | Up
Photography (Basic) - Introduction to photography and other graphic techniques | Next
Figure 10-16.–Leading 35mm film on wire reel |
Figure 10-14.–Reel processing rack.
with a film clip. Dry the hangers, after washing them in
hot water, without film in them.
With suitable racks designed to hold reels, roll film
can also be processed in tanks (fig. 10-14).
TANK DEVELOPING ROLL FILM
have formed. Start the timer and agitate the film for 1
minute. After the first minute of development, agitate
for 5 seconds at l-minute intervals.
The most convenient and reliable way to hand
process roll film is in a small roll-film tank. The
construction of tanks and reels differ somewhat among
The processing tank usually has enough space for
several additional hangers. However, this space is
needed for proper agitation of the film hangers.
Agitation should be accomplished by lifting the hangers
out of the tank draining them momentarily from a
the various manufacturers’ models, resulting in
10-21
differences in loading and use. Generally, the basic unit
used in Navy imaging facilities consists of a stainless
different comer each time, and replacing them in the
solution (fig. 10-13). Hangers should not be agitated too
vigorously from side to side. This forces the developer
through the holes in the hangers at high speed, causing
developing trails near the holes. The objective is to
assure an even flow of fresh solution over the surfaces
of the films regularly according to a fixed schedule.
About 10 seconds before completion of the
developing time, lift each of the hangers out of the
solution, let them drain for 10 seconds, then lower them
into the stop bath. Agitate them several times in the stop
bath, drain them, lower them into the fixing bath, and
agitate them constantly for 2 or 3 minutes.
The fixing and the washing requirements are the
same as described previously in this chapter. When
washing is complete, place the film hangers and film
into a wetting agent; then remove each sheet from its
hanger and hang it up by one corner to dry.
When the film is dried in the hangers, there is a
number of drying marks along the edges of the film, thus
reducing the actual usable size of the negative image. It
is better to suspend each film individually from a line
rewound, you do not have to open the cassette to remove
the film. The leader or loading tab on 35mm film can be
cut off square while in the light to ease loading of the
spiral reel (fig. 10-15).
Figure 10-15.–Cutting leader tab film 35mm film.
steel, center feed, spiraled reel to hold the film; a tank
with a lighttight cover; and a filler cap. Each reel is
constructed for a specific size roll of film; for example,
35mm, 120, and 220. The tank top permits pouring the
chemicals in and out of the tank under white light
conditions. The tanks come in sizes to hold from one
35mm reel to as many as eight 35mm reels or five 120
reels. Small roll-film tanks of all metal construction
(tanks, lids, caps) should be numbered or marked in such
a way that prevents mixing different tanks, lids, and
caps.
The proper loading of a film reel in total darkness
can be the most important steps and challenges in
processing roll film.
When processing roll film with a paper backing, the
paper tape sealing the exposed roll should not be broken
until the lights have been turned out. Also, for 35mm
film, the cassette should not be opened until the lights
have been turned out. If a short length of film is left
protruding from the 35mm cassette when the film is
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