What do acutance dyes do?

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by michael_r, Feb 11, 2013.

  1. michael_r

    michael_r Subscriber

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    How do acutance dyes work - in laymen's terms?

    I think normally "acutance" is defined as the average gradient across a knife edge exposure (measured with a microdensitometer).

    So, do these dyes help to increase the gradient by reducing irradiation/light scatter during exposure? Or do they act "chemically" during development either on the grains themselves or by reducing infectious development effects, diffusion etc?

    Thanks
     
  2. AgX

    AgX Member

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    Acutance dyes are embedded in the emulsion. They are intended to built up opacity to stray-light originating from reflections within the emulsion.
     
  3. michael_r

    michael_r Subscriber

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    Thanks.