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  1. #1
    Mustafa Umut Sarac's Avatar
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    Loading ordinary BW Film with carbon or palladium

    I have few questions ,

    Is it possible to tone the ordinary film with carbon after film development

    or loading the ordinary film after exposure, before development with carbon or palladium

    or load the ordinary film emulsion before exposure and development with carbon or palladium ?

    So , it might be interesting to turn to this to a new process .

    Umut
    Istanbul

  2. #2
    holmburgers's Avatar
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    Ok, a few more questions to your questions.

    What exactly do you mean by "tone with carbon" and "load the film..."?

    By carbon are you referring to the use of dichromates and hardening of the gelatin, or specifically the pigment aspect?

    Once you have a piece of developed film, or paper, you can use a dichromate bleach (carbro bleach) that will harden the gelatin that is insitu with the silver. This would allow you to do a number of things with dyes and/or inks, imbibition or bromoil. Donisthorpe used a uranium toner to make dye-matrices from ordinary film, and probably others used similar techniques too.

    Thomas Manly invented "ozobrome", which I think could be used in a similar way; you bleach a film in a dichromate bath of sorts and then apply the pigments.

    Or, you can take a normal film, developed and fixed (non hardening!) and then sensitize that with a dichromate, and expose it to sunlight. The silver image that is already there will act the same as a negative placed on top, and perhaps it can be etched with hot enough water.

    I'm not super confident in these answers of mine, but maybe it'll get your brain running?
    If you are the big tree, we are the small axe

  3. #3
    Mustafa Umut Sarac's Avatar
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    Chris ,

    Thank you very much , now , I will think and reread your post and post here whatever I found.

    Yes , very informative post.

    Umut

  4. #4
    Mustafa Umut Sarac's Avatar
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    Chris ,

    All are wonderful suggestions.

    Umut

  5. #5
    Mustafa Umut Sarac's Avatar
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    Is there any easy to find , non poisonous bleach resulting like dichromate ?

    Umut

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    holmburgers's Avatar
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    If you are the big tree, we are the small axe

  7. #7
    Mustafa Umut Sarac's Avatar
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    Do chrome alum havent got any health side effects ? One day I wanted to write my notes on my notebooks with dollar green ink , I researched the ink composition and found that chrome was used and chrome effects your childs. But I dont know chrome alum have this ?

    Do you know something ?

    And could you please simplify the ozobrome process ? I really did not understand it.

    thank you ,

    Umut
    Last edited by Mustafa Umut Sarac; 07-14-2011 at 12:27 PM. Click to view previous post history.

  8. #8
    holmburgers's Avatar
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    To be honest, I don't know about a safer bleach.

    Let me read the Ozobrome description that I posted and I will come back with a concise explanation. For now though, it was the precursor to the carbro process.

    Be back in a jiffy...
    If you are the big tree, we are the small axe

  9. #9
    holmburgers's Avatar
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    Ok. So my description of the ozobrome process was somewhat flawed. "you then apply the pigments" is incorrect. It's actually just the classic carbro print. You have a b&w print (bromide), and you have a carbon tissue ("pigment plaster"). You soak the tissue in a sensitizing solution, and then bring the two sheets together and let them sit. The sensitizer reacts with the silver image of the bromide and hardens the gelatin in the tissue; this chemical reaction replaces the action of UV in carbon printing.

    Long story short, that doesn't really fit your original interest.

    There are dye mordanting processes as well, which are unlike carbon or palladium, but can be used with ordinary films. You take a developed film (a positive) and use a certain bleach that turns the silver into some other form; potassium iodide or something?? Not sure right now... Anyways, that is a strong mordant for basic dyes, and they will cling strongly only to the portions that had a silver image. Then you can bleach the silver away; leaving a brilliant dyed image.
    If you are the big tree, we are the small axe

  10. #10

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    Chromium has several oxidation states, +2, +3, and +6. It is the +6 state found in the dichromate ion that is so poisonous. Potassium chrome alum is not dangerous. Most chemicals used in photography are safe if you don't ingest them
    Last edited by Gerald C Koch; 07-14-2011 at 01:57 PM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

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