Table 10-1.-Negative Defects: Their Appearance, Cause, and Remedy-Continued
Defect
Appearance
Cause
Remedy
Streaks.
Streaks and patches. In the
case of spots, may be dark,
white, or transparent.
May be due to uneven
development, caused by
insufficient agitation. May also be
due to developer splashed on the
film before development, a dirty
tank, fixer tray or tank used for
developing, or a light fog. If the
edges of the film are clear, trouble
is in the camera; if the edges are
fogged, it is due to a light leak in
the film magazine or processing
tank. Certain types of resinous
woods and varnishes cause dark
patches. White or transparent
patches may be due to
obstructions in the camera that
prevented light from acting on the
film; an oil or grease that
prevented action of the developer;
hypo on film before development.
Drying marks in the form of
teardrops or white patches are
caused by splashes of water on a
dry negative or by leaving spots of
water on the film before drying,
especially if the film is dried in
warm air.
Trace the cause of the
streaks. In many cases,
they can be avoided in
the operation and
maintenance of
equipment. When
drying negatives, be
sure to use wetting
agent or stabilizer.
PROCESS MONITORING
To consistently produce the highest quality
photographic products possible and to prevent chemical
processing defects, you must monitor the photographic
processes. From a hand-processing system to a
sophisticated, computerized processing system, process
monitoring is necessary to achieve high quality on a
consistent basis. When it is performed routinely, process
monitoring can detect minor problems before a major
casualty to your imagery results as well as aid in the
proper replenishment of your processing system.
The area of quality control and process monitoring
can be very complex. Some Navy Photographer's Mates
earn an NEC and specialize in the field of quality control
for photographic processes. It is not the intention of this
training manual to provide you with the information
necessary to become a specialist in photographic quality
control; however, you must learn the appropriate steps
to monitor the process.
The production of high-quality photographic
products requires control over all the factors that affect
light-sensitive materials. Film exposure and processing
are the most important of these factors. Negatives or
positives that have not been uniformly and correctly
exposed and processed may provide unusable results.
By monitoring the process and providing high-quality
products, you can save time and operating costs by
reducing waste and retakes.
Any monitoring system for the photographic
process requires a reference or standard, and
comparison of daily production to this standard. Visual
comparison of the reference to the standard is very
subjective and limited in accuracy because of personal
opinion. A more accurate method is to measure your
production against the standard. Two means of making
10-38

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