De sensitizing film rather than Hyper sensitizing

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I am curious is there an opposite to hyper sensitizing film? Is there a treatment that can be done to a film to reduce its speed without effecting its normal characteristics. ( I AM NOT INTERESTED IN ND FILTERS OR PULLING FILM)
 

holmburgers

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Interesting question. When you talk about hyper-sensitizing film, are you referring to techniques used by astronomers and such to reduce reciprocity failure? (http://www.astropix.com/HTML/I_ASTROP/FILM/HYPERING.HTM)

Other than aging it somehow, I'm not sure I have any advice. What do you have in mind? Although you're just curious, there has to be something that sparked this idea, eh?

Cheers
 

Ian Grant

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Use a PPD developer, they can knock film speed down by 2-4 stops particularly if no other dev agent is used.

p-Phenylenediamine / para-Phenylenediamine is a weak colour developing agent used in ultra fine grain developers, it was used on it's own in Sease 1 and with Glycin in Sease 2, 3 & 4 or in equal molecular parts with Pyrocatechin to form Meritol in Johnsons developers.

Ian
 
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