1. kevin klein

    kevin klein Member

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    What could be the efect of extra iodide addition to an emulsion, such as two or three times as much as called for?
     
  2. Photo Engineer

    Photo Engineer Subscriber

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    Kevin;

    You can go as high as 10%, but with SR emulsions with no digest (ammonia), you will place the iodide in the core where its effectiveness is limited.

    You can go higher too, but then the emulsions begin to lose contrast severely and become difficult to develop.

    Fog generally goes up as a function of iodide content, but it depends on emulsion type and addition method.

    I stay between 0.3 and 3.0% (mole/mole).

    PE