Basic Photography Course

3. Fix-dark or appropriate safelight

4. Wash-white light

5. Dry-white light

In addition to exposure, there are four factors in

development that control image density, contrast, and,
to a limited degree, the uniformity of individual
densities in a negative. These four factors are the type
of developer used, development time, temperature of the
developer, and agitation as follows:

Type of developer. One type of developer cannot

cover all film exposure/processing situations. For
example, film exposed under poor lighting conditions
may require a vigorous developer to bring out as much
image detail as possible, while film exposed under
normal conditions requires a normal working developer.
There are many different developers, each provides a
different activity and quality of development. The actual
choice of the developer to use depends on the following:
the type of film, conditions under which it was exposed,
type of negative required, developing time that is best
for the method of development to be used, and the

manufacturer's recommendation.

Time and temperature. Many factors must be

considered if you want to ensure correct development
during film processing. Two of these factors are the
length of time the film is allowed to develop and the
temperature of the developer solution. Both factors can

have a significant impact on the quality of the processed
film.

10-15

The normal temperature for hand processing most

black-and -white film is 68°F (T-Max film with T-Max
developer is 75°F). There are several reasons for this

standardization. At a temperature of 68°F, the gelatin
swells sufficiently to allow adequate penetration of the
developing solution without oversoftening to the point
where it is easily damaged (which occurs at higher
temperatures). Temperatures lower than 68°F slow
development excessively. Only when time is of the
utmost importance are accelerated temperatures used. In
most instances when high temperatures are used, the
film is treated in a hardening bath before processing, or
the film is designed specifically for being processed at
such temperatures. Since a rise of several degrees in
temperature shortens development only a small amount,
there is little to be gained by deviating from standard
processing temperatures.

As explained earlier, the activity of a developer

increases as its temperature increases. Film
development carried out for a given time at a given
temperature produces both predictable and desired
results-assuming, of course, that the film has been
exposed properly. When film is developed for a given
time at a given temperature, it is called "time and
temperature development."

When you know the time and temperature

relationship for a given film and developer combination,
processing in total darkness becomes simple. You
simply adjust solutions to the prescribed temperature
and then process the film for the required time.
Assuming proper exposure, time and temperature
processing can produce a correctly developed negative
without your having to see what is happening in the
solution.

In the time and temperature method of film

processing, as in any method of film processing, if the
film is developed for too short a time or at too low a
temperature, a weak, low-contrast image results.
Underdevelopment can result in insufficient highlight
density. On the other hand, if the negative is developed
for too long a period or at too high a temperature, the
result is a negative having too much density. The
developer solution overdevelops the exposed areas and
may even develop some of the unexposed silver halides.

All solution temperatures (developer, rinse, fix, and

wash) should be as close to each other as possible. When
there is considerable difference in the temperature of the
solutions, excessive graininess may result, or the
emulsion may be subject to excessive expansion and
contraction that causes it to wrinkle or crack This effect
is called reticulation. Since reticulation is not correct-
able, it causes the negative to be useless for printing.

For correct development, both time and temperature

must be accurately controlled. Within limits, time can

The temperature of solutions may be adjusted by

surrounding them with hot water, cold water, or ice.
Never add water or ice directly to a solution because it
dilutes the developer to an unknown degree. Ice may be
placed in a container and suspended in the solution. An
immersion heater may be used in the solution to raise its
temperature.

be adjusted for a given temperature, or temperature can
be adjusted for a given time.

There is a definite correlation between time and

temperature. When it is impossible to maintain solution
temperature at the desired level, time can be shortened
or lengthened to compensate. As the temperature
increases, developing time must be decreased to provide
equivalent development. As the temperature decreases,

development time must be increased.

contents

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 -> 3. Fix-dark or appropriate safelight 4. Wash-white light 5. Dry-white light In addition to exposure, there are four factors in development that control image density, contrast, and, to a limited degree, the uniformity of individual densities in a negative. These four factors are the type of developer used, development time, temperature of the developer, and agitation as follows: Type of developer. One type of developer cannot cover all film exposure/processing situations. For example, film exposed under poor lighting conditions may require a vigorous developer to bring out as much image detail as possible, while film exposed under normal conditions requires a normal working developer. There are many different developers, each provides a different activity and quality of development. The actual choice of the developer to use depends on the following: the type of film, conditions under which it was exposed, type of negative required, developing time that is best for the method of development to be used, and the manufacturer's recommendation. Time and temperature. Many factors must be considered if you want to ensure correct development during film processing. Two of these factors are the length of time the film is allowed to develop and the temperature of the developer solution. Both factors can have a significant impact on the quality of the processed film. 10-15 The normal temperature for hand processing most black-and -white film is 68°F (T-Max film with T-Max developer is 75°F). There are several reasons for this standardization. At a temperature of 68°F, the gelatin swells sufficiently to allow adequate penetration of the developing solution without oversoftening to the point where it is easily damaged (which occurs at higher temperatures). Temperatures lower than 68°F slow development excessively. Only when time is of the utmost importance are accelerated temperatures used. In most instances when high temperatures are used, the film is treated in a hardening bath before processing, or the film is designed specifically for being processed at such temperatures. Since a rise of several degrees in temperature shortens development only a small amount, there is little to be gained by deviating from standard processing temperatures. As explained earlier, the activity of a developer increases as its temperature increases. Film development carried out for a given time at a given temperature produces both predictable and desired results-assuming, of course, that the film has been exposed properly. When film is developed for a given time at a given temperature, it is called "time and temperature development." When you know the time and temperature relationship for a given film and developer combination, processing in total darkness becomes simple. You simply adjust solutions to the prescribed temperature and then process the film for the required time. Assuming proper exposure, time and temperature processing can produce a correctly developed negative without your having to see what is happening in the solution. In the time and temperature method of film processing, as in any method of film processing, if the film is developed for too short a time or at too low a temperature, a weak, low-contrast image results. Underdevelopment can result in insufficient highlight density. On the other hand, if the negative is developed for too long a period or at too high a temperature, the result is a negative having too much density. The developer solution overdevelops the exposed areas and may even develop some of the unexposed silver halides. All solution temperatures (developer, rinse, fix, and wash) should be as close to each other as possible. When there is considerable difference in the temperature of the solutions, excessive graininess may result, or the emulsion may be subject to excessive expansion and contraction that causes it to wrinkle or crack This effect is called reticulation. Since reticulation is not correct- able, it causes the negative to be useless for printing. For correct development, both time and temperature must be accurately controlled. Within limits, time can The temperature of solutions may be adjusted by surrounding them with hot water, cold water, or ice. Never add water or ice directly to a solution because it dilutes the developer to an unknown degree. Ice may be placed in a container and suspended in the solution. An immersion heater may be used in the solution to raise its temperature. be adjusted for a given temperature, or temperature can be adjusted for a given time. There is a definite correlation between time and temperature. When it is impossible to maintain solution temperature at the desired level, time can be shortened or lengthened to compensate. As the temperature increases, developing time must be decreased to provide equivalent development. As the temperature decreases, development time must be increased. contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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