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
The normal temperature for hand processing most
black-and -white film is 68F (T-Max film with T-Max
developer is 75F). There are several reasons for this
standardization. At a temperature of 68F, 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 68F 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
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
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.

Basic Photography Course

Privacy Policy