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  1. #1
    Athiril's Avatar
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    Manipulating silver iodide image

    Long story short,

    I have a film strip with images made of what I assume is only or mostly silver iodide (or other non developable silver salts).

    It is an E-6 film, the machine borked, and the film sat in the first dev at processing temp (with no agitation) for an hour or so, I was going to rehal it into a colour neg as there was fine negs on the film, but I had already hit the colour dev by that stage and didn't want to stack a neg on a pos.

    Anyway, the results are, quite thin black and white positives, which survived the bleach and fix. There is no dye.

    This has happened once before, when T-Max was accidentally run through it (inc bleach and fix), it gave the same results, thin black and white positives.



    Assuming it's a silver layer that won't budge with any combination of steps of bleach, colour dev etc (and fix), what can I do to get this to a developable silver salt? I can then rehal it over and over to reasonable density slides.

    Eg; such as passing the film through chlorine gas to get it to silver chloride?

    Would a ferricyanide/bromide bleach do the trick and displace the iodide, that PDTA based bleach doesn't seem to?

    Regards.

  2. #2
    Photo Engineer's Avatar
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    Dan;

    Have you ever considered that it might have formed Ag2S, Silver Sulfide? This can happen. It becomes a mess as nothing can react with it.

    PE

  3. #3
    Athiril's Avatar
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    Thanks PE,

    That does make sense.


    Hmm, what about the trick to remove silver tarnish with aluminium? I could dissolve some alfoil in fixer, and add bicarb?

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    Photo Engineer's Avatar
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    IDK what it would accomplish. But, let us know.

    PE

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    Ron,

    If there really was any Ag left in the film, it sounds like a case for a cohex amplifier from the old days.

  6. #6
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    Yeah, that would work. But, AgI and Ag2S both poison the catalysis.

    So, IDK what would work.

    PE

  7. #7
    Athiril's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    IDK what it would accomplish. But, let us know.

    PE
    Electrochemical reduction of Silver Sulphide to Silver, but the Silver Sulphide needs to be in contact with the aluminium (which takes up the sulphide) in an electrolytic solution iirc.

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    At this point, you really don't know what the image is made of, do you? Is it Ag based or dye based?

  9. #9
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    Quote Originally Posted by Athiril View Post
    Electrochemical reduction of Silver Sulphide to Silver, but the Silver Sulphide needs to be in contact with the aluminium (which takes up the sulphide) in an electrolytic solution iirc.
    I got that, but Fred put it better than I did.

    We don't know for sure what the yellow is for sure. Sorry for the misunderstanding.

    PE

  10. #10

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    The original poster said "Anyway, the results are, quite thin black and white positives, which survived the bleach and fix. There is no dye." And I wondered how he arrived at the conclusion there was no dye.

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