Basic Photography Course

clearly defined detail in all parts of the image from the
strongest highlights to the weakest shadows. The

contrast is satisfactory. It may not reproduce the contrast
of the original scene exactly, but it has sufficient contrast

to produce a pleasing reproduction.

When the film is overexposed and normally

developed, as in No. 8, the highlights in the image show
a loss of detail. Giving the overexposed film less than

normal development may save some highlight detail,
but it also reduces the contrast. When the overexposed
film is overdeveloped, as No. 9 was, all highlight detail
is destroyed and the contrast is also reduced.

Table 10-1 is a listing of defects that commonly

occur in film processing. The appearance, the cause, and
the remedy for each of the defects listed are also
provided.

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

Defect

Appearance

Cause

Remedy

Abrasion
marks or
streaks.

Fine black lines, usually
resembling pencil scratches
and running in the same
direction.

Friction on emulsion caused by

Great care should be

improper handling or storage. Dirt,

taken in storage of film.

or grime, in camera or magazine.

Boxes containing film
should be stored on
end, so no pressure is
exerted on the surface
of the emulsion. Care,
also, should be taken
not to rub or drag
sensitized material over
a rough surface. Be
sure camera back or
magazine is clean and
free from dirt, or grime.

Air bubbles.

An air bubble occurring

Transparent spots occurring in the

Immerse film carefully

during development shows

developer are caused by bubbles

and thoroughly in

as a small, transparent spot.

of air on the surface of the

developing and fixing

Sometimes minute dark

emulsion. These prevent the

solutions. Move film

streaks lead from the spot.

developer from coming into

during development

When the negative is rocked

contact with the emulsion.

and fixation to break up

in a tray, streaks project from

Darkened streaks are the result of

and prevent air bells.

each side of the spot in the

excess oxidation of the developer,

Water always contains

direction the tray was

caused by air in a bubble. Dark

some air and when

rocked. If the tray is rocked

spots that occur in the fixing bath

there is a rise in

in two directions, streaks

are caused by a pocket of air

temperature, air is

form a cross with a

holding the fixer away from the

expelled and gathers in

transparent spot in the center.

emulsion and allowing a slight

the form of small

In tank development. dark

continuation of development.

bubbles on the inside of

streaks usually form at the

the tank and also on the

lower edge of the transparent

surface of the film

spot. In the fixing bath they

during preliminary

show as small, round, dark

stages of development.

spots.

10-34

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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 -> clearly defined detail in all parts of the image from the strongest highlights to the weakest shadows. The contrast is satisfactory. It may not reproduce the contrast of the original scene exactly, but it has sufficient contrast to produce a pleasing reproduction. When the film is overexposed and normally developed, as in No. 8, the highlights in the image show a loss of detail. Giving the overexposed film less than normal development may save some highlight detail, but it also reduces the contrast. When the overexposed film is overdeveloped, as No. 9 was, all highlight detail is destroyed and the contrast is also reduced. Table 10-1 is a listing of defects that commonly occur in film processing. The appearance, the cause, and the remedy for each of the defects listed are also provided. Table 10-1.Negative Defects: Their Appearance, Cause, and Remedy Defect Appearance Cause Remedy Abrasion marks or streaks. Fine black lines, usually resembling pencil scratches and running in the same direction. Friction on emulsion caused by Great care should be improper handling or storage. Dirt, taken in storage of film. or grime, in camera or magazine. Boxes containing film should be stored on end, so no pressure is exerted on the surface of the emulsion. Care, also, should be taken not to rub or drag sensitized material over a rough surface. Be sure camera back or magazine is clean and free from dirt, or grime. Air bubbles. An air bubble occurring Transparent spots occurring in the Immerse film carefully during development shows developer are caused by bubbles and thoroughly in as a small, transparent spot. of air on the surface of the developing and fixing Sometimes minute dark emulsion. These prevent the solutions. Move film streaks lead from the spot. developer from coming into during development When the negative is rocked contact with the emulsion. and fixation to break up in a tray, streaks project from Darkened streaks are the result of and prevent air bells. each side of the spot in the excess oxidation of the developer, Water always contains direction the tray was caused by air in a bubble. Dark some air and when rocked. If the tray is rocked spots that occur in the fixing bath there is a rise in in two directions, streaks are caused by a pocket of air temperature, air is form a cross with a holding the fixer away from the expelled and gathers in transparent spot in the center. emulsion and allowing a slight the form of small In tank development. dark continuation of development. bubbles on the inside of streaks usually form at the the tank and also on the lower edge of the transparent surface of the film spot. In the fixing bath they during preliminary show as small, round, dark stages of development. spots. 10-34 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
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