Manual Film Processing Clifford R. Berry, DVM Adjunct Associate Professor, University of Tennessee Veterinary Specialists Center, Maitland, FL ACVR Artifacts
Jan 22, 2016
Manual Film Processing
Clifford R. Berry, DVMAdjunct Associate Professor, University of Tennessee
Veterinary Specialists Center, Maitland, FL
ACVR Artifacts
Manual Film Processing
Manual film processing involves dipping the exposed film into tanks of developer, fixer and wash.
The chemical are held in stainless steel tanks.
The water should be running and draining.
Temperature of developer and fixer must be known for adequate development.
Manual film processing
Developer Fixer
Developer
Chemical must be stirred before submerging the film into the chemicals or there will be heterogeneous development of the film.
Stirrers should be kept separate.
Developer
Time-Temperature technique.
680F = 5 minutes.
A mechanical timer with a bell is used to time the duration of development and fixing since the room will be dark
Film Hanging
The films are placed on hangers to hold the films within the tank.
Metal clips poke through the film in order to hold onto the film.
Be sure that films are not touching.
If developing multiple films, beware of safety light fog.
Manual Film Processing
The edges of the film will be punctured by the hanger and can be used to identify manual processed films.
Film corners may be cut.
Seen on all four corners.
Manual Film Processing
The films can be air dried
Dryers are available to speed the process of drying films
Manual film processing
Tanks should be covered when not in use to prevent the developer from oxidizing.
Chemical should be replaced on a regular basis.
Film Too Light
Underdeveloped
Exhausted Chemistry
Underexposed
Manual Film Processing
Exhausted DeveloperDeveloper time has to
increase to due oxidized developer and with prolonged contact with the developer chemical all crystals (exposed and unexposed) are reduced results in poor contrast.
Common Artifacts Associated with Film Processing
Low fixer level
The entire film was developed but the top portion was not fixed or cleared.
Chemistry Levels Uneven/Low
Low developer and fixer level
The top of the film was never fixed or developed
Low developer and
Fixer (higher level than developer)
The green strip at the top is the portion of the film not developed or fixed
Chemistry Levels Uneven/Low
Development - Kiss Artifact
Cleared emulsion on reflected light.
Matching radiograph to accompany
Fixer - Kiss Artifact
Developed but emulsion not
cleared so “milky” or colored
appearance (sheen) still
present at place where two films where in contact within the fixer.
Emulsion Wrinkle/Peel
Emulsion wet enough that peels away
from the film base.
Emulsion Peel
Lack of Wash - Fixer Oxidation
Formation of Silver Sulfide
Debunking Solarization
Solarization -
Process for making copy films by overexposure such that a reversal of optical densities are produced when exposed to light.
Rebromination hypothesis considered likely explanation at this time.
Optical reversal occurs after prolonged exposure of the film so that there is a reversal of the H & D curve.
Correct manual processing artifact = Sabatier Effect
Sabatier Effect
White light exposure of the radiograph while in the developer (manual processing).
Results in the silver grains in the areas that are “white” non-exposed becoming developed to Dmax. The partially developed areas are less affected by the light exposure.
Creates characteristic lines of demarcation called “Mackie lines.”
Sabatier Effect
Incomplete fixation
Colored FilmPink – on view boxGreenish with reflected lightDue to exhausted fixer, incomplete fixation or insufficient
rinsing
Non Stirred Developer
Developer - Specific Gravity Effects
Developer Specific Gravity will cause the “strongest”,
non oxidized developer to settle to the bottom of the
developer tank.
Sight Development
Cathedral Effect
Film Fog - Safety Light
Manually processed.
Light leak or inappropriate safe light in dark room.
Note the shadow (minus density) created by the
film hanger.