REDUCERS

byTed Peterson
When you have a correctly exposed negative of a contrasty picture and is overdeveloped, the negative can be improved sometimes if a reducer is used that removes a larger fraction of the silver deposit from the areas corresponding to the highlights of the subjects. This is called a superproportional reducer. If the complete negative is overdeveloped, this calls for a reducer that will remove an equal fraction of the silver thus decreasing the contrasts of the negative. These are called proportional reducers.
Farmer reducers is the reducer that is used most of the time for this. The only trouble that you may have is being able to pick up Potassium ferricyanide. You cannot ship it across a state line. (US law). I ran into this when I was selling chemicals.
The materials necessary to produce this do not keep well together. You can make two stock solutions if necessary.
Solution A.
Potassium ferricyanide 2 1/2 ounces.
Water to make 32 ounces.
Solution B.
Sodium thiosulfate (hypo).
Water to make 32 ounces.
To use, 1 part of A is mixed with 3 parts of B and 30 parts of water. It will take from 1 to 5 minutes. Watch it. At that point throughly wash the negative. This makes superproportional reducers.
To make it work as a proportional reducer you will use it as a 2 step development. First immers the negative in solution A for from 1 to 4 minutes and then into solution B for 2 minutes and then wash it. There are a lot of other reducers out there but this is the one most people will use.
Be careful with this as Potassium ferricyanide is what they use in gas chambers. Make sure the you have the windows open.
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