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  1. #21

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    PE, it raises a question for me, based on discussions I've been having with people on other staining developer threads. What is your take on after-development effects on stain? The conventional wisdom regarding most Pyro and Catechol developers is that for maximum imagewise stain, the entire process should be kept both neutral to alkaline, and sulfite free. The key implications being:

    a. Acid stop baths and/or fixers can reduce or disolve stain after development
    b. Both fixers containing a significant amount of sulfite preservative, and say a typical sulfite-based hypo clearing agent can reduce stain after development
    c. Somehow imagewise stain can actually be intensified with some developers/films if the after-development process is alkaline and sulfite-free

    Gerald Koch disagrees, at least with (b) since he says the image stain is not soluble in a sulfite-rich solution once development is complete.

    Thanks
    Michael

  2. #22
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    Well, I will find out fairly soon. I will slice an identically-exposed roll into thirds after development, and fix one of each in Flexicolor, TF-5, and an alkaline fixer (possibly TF-4 if PE responds that it is indeed alkaline), respectively. I will make an enlarged contact sheet using my 8x10 enlarger and see if there are any differences between the thirds.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

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  3. #23
    Greg Davis's Avatar
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    I always felt the pinholes were created by the drastic change from the alkali developer to the acidic fixer. Perhaps my diluted stop bath allowed the film to acclimate before the more acidic fix. Perhaps the film has changed since I stopped shooting it.
    www.gregorytdavis.com

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  4. #24
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    I have a bunch of answers here!

    1. I am no expert on staining developers. I don't use them. So, the tests that I have seen were run by others and were merely reported to me directly or via others. Sorry. However, I do know that some stains come from quinones or quinones reacted with gelatin. Chemically, quinones are destroyed by Sulfites. So, there is a possible clue. And, Sulfites are (IIRC) more active in this regard at acid pH.

    2. TF-4 is about pH 8.

    3. Many films develop pinholes regardless of process. The pinholes are latent in the coating in the form of bubbles in the melt and soft coatings. During processing, in some workflows, the pinholes "burst" leaving - well - pinholes.

    The last report I saw that was official regarding pinholes was in the 50s and was written up by George Eaton. Since then, AFAIK, no Kodak or Ilford film has been demonstrated to have them.

    PE

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