What is the ratio for the chemicals need for film photography?
i need the ratios developing both negatives and photographs for black and white photography
developer
stop bath
fixer
developer
stop bath
fixer
Best AnswerAsker's Choice
Film and paper emulsions are virtually the same from a chemical
standpoint; we could process both using the same chemicals applying the
same processing steps. While this is possible, we prefer to handle
paper and film differently to gain optimum results. Films have an
emulsion coat that is more than twice as hefty as paper. This is
because films are viewed, printed, and scanned via one light pass thru
the emulsion. Contrariwise we view prints via two light passes. Light
from a nearby lamp plays on the print. This light transverses the
emulsion, strikes a white undercoat and reflects backward transversing
the emulsion again on its path to our eye. The two pass light path
greatly reduce the amount of light sensitive coat needed. This
translates to the fact that prints only require 90 – 120 seconds to
develop whereas films generally require 5 – 10 minutes. Additionally we
use a milder developer on film and often this developer contains a
silver solvent to reduce grain size so the film can tolerate enlarging.
After developing, we stop this action with a water rinse or a bath in a mild acid like vinegar. Both film and paper are treated about the same.
After the stop bath we fix the film and paper to render the image permanent. While two different fix chemicals are available, we have universally settled on ammonium thiosulfate. This solution acts 50% faster than plain fixer which is sodium thiosulfate. The faster fixer is nicknamed rapid fix. For film we dilute rapid fix 3 parts water 1 part fix concentrate. For paper the dilution is 7 parts water 1 part concentrate. Paper requires the more dilute fix as a more robust fix will begin to attack the silver black and white image this lightens the print. Fix time for film I 2 -7 minutes. For paper it is 45 -70 seconds.
After developing, stop bath, and fix both paper and film must be washed to flush out residual chemicals as these stain and tarnish the image. Film rinses clean is 20 minutes; papers can take 1 hour or more. We can use a chemical rinse to purge and neutralize residual chemicals. A few minutes in hypo clear followed by a few minutes wash will do the trick for both. Many modern papers are coated on a waterproof plastic base made of synthetic tree resin. This resin coat (RC) prevents the retention of chemicals in the paper thus wash time is now super quick.
After developing, we stop this action with a water rinse or a bath in a mild acid like vinegar. Both film and paper are treated about the same.
After the stop bath we fix the film and paper to render the image permanent. While two different fix chemicals are available, we have universally settled on ammonium thiosulfate. This solution acts 50% faster than plain fixer which is sodium thiosulfate. The faster fixer is nicknamed rapid fix. For film we dilute rapid fix 3 parts water 1 part fix concentrate. For paper the dilution is 7 parts water 1 part concentrate. Paper requires the more dilute fix as a more robust fix will begin to attack the silver black and white image this lightens the print. Fix time for film I 2 -7 minutes. For paper it is 45 -70 seconds.
After developing, stop bath, and fix both paper and film must be washed to flush out residual chemicals as these stain and tarnish the image. Film rinses clean is 20 minutes; papers can take 1 hour or more. We can use a chemical rinse to purge and neutralize residual chemicals. A few minutes in hypo clear followed by a few minutes wash will do the trick for both. Many modern papers are coated on a waterproof plastic base made of synthetic tree resin. This resin coat (RC) prevents the retention of chemicals in the paper thus wash time is now super quick.
Other Answers (2)
Rated Highest-
I use D-76 1:1 when processing black and white film. When I need to push Tri-X to 1200 ISO, I develop it in Acufine, no dilution
With film I use water with no agitation for the first full minute. This allows the shadow area of the film to continue developing to add a little more dynamic range to the film. If you are afraid that the remaining developer will shorten the life of your fixer, you can just rinse the film a few times with plain water.
Fixer needs to be agitated for the first full minute and every thirty seconds there after until you have full fixed the film. How you know how long that is, you take a piece of the film (from the film leader) and drop it into the graduate with the fixer in it. Without any agitation, time how long it takes for the film to clear. Double that time and your film will be fully fixed when you finish your fixer stage. Fixer is never diluted
Wash in a film washing device for at least 1/2 hour.
Dip the washed film in a clean graduate cylinder filled with distilled water and a few drops of PhotoFlo to prevent streaking as the film drys overnight in a dust free location
Dektol is usually mixed from power and its dilution is 1:2 and the RC paper is developed for 90 seconds with constant agitation. Fiber based paper is developed for 120 seconds with constant agitation
Indicator stop bath is used at 1:63 dilution
Fixer is used with no dilution and constantly agitated for at least 5 minutes.
Hypo-eliminator is used to reduce wash times of fiber based paper.
Wash times are from 30 minutes to one hour depending upon whether you are using an archival print washer or a large print tray with siphon.
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It depends on what kind of developer you are using, whether it is liquid or powder to begin with (powder has to be mixed first, then diluted). Some types require no dilution, while others can be diluted 1:50 (agfa rodinol). So more info is needed.
Stop bath and fix: follow the directions on the label.
For processing prints, again it depends on the type of developer you are using. Dektol can be used straight (mixed from the powder) or up to a 1:9 dilution.
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