Basic Photography Course

Figure 10-9.Washing film in processing roll-film tank.

through the tank and around the film at a rapid rate. By
discharging the water from the top of the tank, you can
remove more hypo in a shorter time.

Roll film also can be washed in the roll-film tank in

which it was processed. To wash roll film in a roll-film
processing tank, simply push a small hose down into the

center of the reel and have the faucet turned on, so the
water overflows steadily from the tank (fig. 10-9).

TIMERS

Every darkroom should have a reliable timer.

Ideally, the timer should have both a minute hand and a
sweep second hand. The timer most commonly used in
the Navy is a Gray Lab timer (fig. 10-10). Not only does
this timer have a minute and sweep second hand but the

numbers and hands are fluorescent so they can be seen
in the dark A Gray Lab timer also has an alarm (buzzer)
that indicates when the time for processing is up.

PROCESSING METHODS

No matter how many rolls or sheets of film you

develop, it helps when you carry out the processing in
three distinct phases, beginning with preparation. First,

your work area must be clean, and the equipment needed
must be arranged so it is easy to locate in the dark The
second phase is processing. If you are not familiar with
darkroom work, you should complete ALL the
processing steps with dummy or practice film and water
to substitute for processing solutions under white light

and then practice a few times in the dark. The third phase
is film drying.

Figure 10-10.Gray Lab timer.

302.285

To make the latent image visible and permanent,

you must process the film in different chemical
solutions. There are five steps in the black-and-white
processing phase. The first step is development. In this
step the film is placed in a developer that transforms the
latent image into a visible black metallic silver image.
In the second step the developing solvents are
neutralized, and development is retarded or stopped by

a rinse bath or acid stop bath, respectively. The third step
involves placing the film into a fixing bath to remove
the light sensitive, undeveloped silver halides. The
fourth step is to wash the film to remove all the
chemicals, and the last step is to dry the film. Each of
these steps is explained further in this chapter, since
there are certain controls that must be applied to each
step.

Some of the processing steps may be carried out in

white light, while others must be done under appropriate
safelight conditions or in total darkness. The steps that
must be done in darkness or under suitable safelight
conditions begin when the film package, holder, or roll
is opened and end when the film is removed from the

fixer.

As discussed earlier, there are five steps in film

processing. The steps and the lighting conditions under

which they are carried out are as follows:

1. Development-dark or appropriate safelight

2. Rinse or stop bath-dark or appropriate safelight

10-14

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Basic Photography Course

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DOFMaster for Windows On-line Depth of Field Calculator DOFMaster for Mobile Devices On-line Depth of Field Table Hyperfocal Distance Chart Articles FAQ Recommended Books Support Contact Links Home As an Amazon Associate I earn from qualifying purchases.	contents <- previous page next page -> Figure 10-9.Washing film in processing roll-film tank. through the tank and around the film at a rapid rate. By discharging the water from the top of the tank, you can remove more hypo in a shorter time. Roll film also can be washed in the roll-film tank in which it was processed. To wash roll film in a roll-film processing tank, simply push a small hose down into the center of the reel and have the faucet turned on, so the water overflows steadily from the tank (fig. 10-9). TIMERS Every darkroom should have a reliable timer. Ideally, the timer should have both a minute hand and a sweep second hand. The timer most commonly used in the Navy is a Gray Lab timer (fig. 10-10). Not only does this timer have a minute and sweep second hand but the numbers and hands are fluorescent so they can be seen in the dark A Gray Lab timer also has an alarm (buzzer) that indicates when the time for processing is up. PROCESSING METHODS No matter how many rolls or sheets of film you develop, it helps when you carry out the processing in three distinct phases, beginning with preparation. First, your work area must be clean, and the equipment needed must be arranged so it is easy to locate in the dark The second phase is processing. If you are not familiar with darkroom work, you should complete ALL the processing steps with dummy or practice film and water to substitute for processing solutions under white light and then practice a few times in the dark. The third phase is film drying. Figure 10-10.Gray Lab timer. 302.285 To make the latent image visible and permanent, you must process the film in different chemical solutions. There are five steps in the black-and-white processing phase. The first step is development. In this step the film is placed in a developer that transforms the latent image into a visible black metallic silver image. In the second step the developing solvents are neutralized, and development is retarded or stopped by a rinse bath or acid stop bath, respectively. The third step involves placing the film into a fixing bath to remove the light sensitive, undeveloped silver halides. The fourth step is to wash the film to remove all the chemicals, and the last step is to dry the film. Each of these steps is explained further in this chapter, since there are certain controls that must be applied to each step. Some of the processing steps may be carried out in white light, while others must be done under appropriate safelight conditions or in total darkness. The steps that must be done in darkness or under suitable safelight conditions begin when the film package, holder, or roll is opened and end when the film is removed from the fixer. As discussed earlier, there are five steps in film processing. The steps and the lighting conditions under which they are carried out are as follows: 1. Development-dark or appropriate safelight 2. Rinse or stop bath-dark or appropriate safelight 10-14 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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