Basic Photography Course

Table 10-1.Negative Defects: Their Appearance, Cause, and Remedy-Continued

Defect

Blisters.

Appearance

Cause

Remedy

They resemble the familiar

Liquid or gas formed between the

Blisters can be avoided

ones that are caused by slight

emulsion and film support when

by eliminating their

bums on human skin.

the solution has become too warm

causes.

and has loosened the gelatin from
its support. Also, produced by
developer and fixer being too
strongly concentrated. Changing
film from one bath to the next may
cause the formation of gas
between the emulsion and sup-
port. Frequently caused by taking
the film from an alkali solution
and placing it into a strong acid.
Another common cause is
allowing water from a faucet to
flow directly on the emulsion.

Brown spots.

Small brown- or

Produced by oxidized developer or

Avoid exhausted or

sepia-colored areas or spots

by fine particles of chemicals

oxidized developer.

on the negative.

settling on the film before

Keep processing room

development. May also occur

clean and free from dry

during washing, from rust, and

chemicals. Filter the

other impurities in the water.

wash water.

Crystalline

Surface of the negative

Insufficient washing after fixing.

Increase the final wash

surface.

emulsion has a crystalline

Hypo remains in the film and

time.

appearance, resembling frost

crystallizes.

on a windowpane.

Dark lines.

These lines are divided into

The first class is caused by

For the first class, more

two distinct classes. The first

insufficient agitation of the

frequent agitation

class, those that run from

negative in tank development.

during development.

dark areas to more

Cause of the second class is

The remedy for this

transparent areas of the

thought to be of an electrolytic

class aggravates the

negative, and the second

origin.

defect in the second

class, those that run from the

class. Only known

more transparent areas to the

remedy is to remove all

darker areas. In both cases,

film hangers from the

lines are wider, not as clean

tank four or five times

cut, and not nearly as parallel

during the developing

as abrasion marks.

period, holding the
hangers in a bunch, and
allowing the corners of
the hangers to rest on
the edge of the
developing tank for 10
to 15 seconds.

10-35

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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 -> Table 10-1.Negative Defects: Their Appearance, Cause, and Remedy-Continued Defect Blisters. Appearance Cause Remedy They resemble the familiar Liquid or gas formed between the Blisters can be avoided ones that are caused by slight emulsion and film support when by eliminating their bums on human skin. the solution has become too warm causes. and has loosened the gelatin from its support. Also, produced by developer and fixer being too strongly concentrated. Changing film from one bath to the next may cause the formation of gas between the emulsion and sup- port. Frequently caused by taking the film from an alkali solution and placing it into a strong acid. Another common cause is allowing water from a faucet to flow directly on the emulsion. Brown spots. Small brown- or Produced by oxidized developer or Avoid exhausted or sepia-colored areas or spots by fine particles of chemicals oxidized developer. on the negative. settling on the film before Keep processing room development. May also occur clean and free from dry during washing, from rust, and chemicals. Filter the other impurities in the water. wash water. Crystalline Surface of the negative Insufficient washing after fixing. Increase the final wash surface. emulsion has a crystalline Hypo remains in the film and time. appearance, resembling frost crystallizes. on a windowpane. Dark lines. These lines are divided into The first class is caused by For the first class, more two distinct classes. The first insufficient agitation of the frequent agitation class, those that run from negative in tank development. during development. dark areas to more Cause of the second class is The remedy for this transparent areas of the thought to be of an electrolytic class aggravates the negative, and the second origin. defect in the second class, those that run from the class. Only known more transparent areas to the remedy is to remove all darker areas. In both cases, film hangers from the lines are wider, not as clean tank four or five times cut, and not nearly as parallel during the developing as abrasion marks. period, holding the hangers in a bunch, and allowing the corners of the hangers to rest on the edge of the developing tank for 10 to 15 seconds. 10-35 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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