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  1. #1

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    Cyanide in the "Olden" days

    Long ago when I was in university, I took an English writing course that had us read all kinds of essays and then write about them. I have a memory of one essay that was about early photographers and how many of them died because they did not realize how deadly potassium (or sodium) cyanide was. For a reason unknown to me, cyanide was part of the development process then. I am not sure what time frame this essay was dealing with. Anyway, the photographers would bit the cyanide pellets to break them into smaller pieces and then of course, die due to ingestion.

    I really wish I still had that essay!

    Was this true? Was cyanide used as a photographic developing chemical? If yes, when was its use discontinued?

  2. #2

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    I believe it was used as a fixer in wet plate process.
    Develop, stop, fix.... wait.... where's my film?

  3. #3

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    Hard to believe they didn't clue in real fast.
    And how good a photographer could you be if you only had one chance.
    Of course the old live fast, die young and become a tragically lost photographer was invented then.
    "There are a great many things I am in doubt about at the moment, and I should consider myself favoured if you would kindly enlighten me. Signed, Doubtful, off to Canada." (BJP 1914).

    Regards
    Bill

  4. #4

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    Potassium/sodium cyanide was used as a fixing agent for Daguerrotypes and collodian plates.

    As to mortality probably more daguerrotypists died from mercury poisoning than from any other chemical. The mercury fumes would turn gold objects such as watch fobs temporarily silver in color. Mercury is a cumulative poison whereas cyanide is not.
    Last edited by Gerald C Koch; 08-29-2012 at 09:58 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.

    ~Antoine de Saint-Exupery

  5. #5

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    Cyanide was used as part of the process described in Kodak's Mercury Intensifier Formula In-1. Published on Page 37 here: http://www.scribd.com/doc/82834476/K...alsAndFormulae

  6. #6

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    Potassium cyanide is a white granular salt made by the absorption of hydrogen cyanide in potassium hydroxide. It is soluble in both water and alcohol and a lethal poison. If mixed with acids it produces highly toxic hydrogen cyanide gas. This was the preferred fixing chemical for collodion positives because it contained no sulfides to darken the highlight silver. As a fixing agent cyanide was particularly effective. After dissolving the unexposed silver halides cyanide would also remove non-image fog producing very clean shadow areas. Prolonged fixing would eventually remove image silver. Tincture of iodine was added to dilute solutions of potassium cyanide and used to remove unwanted non-image silver in photographic materials and to remove silver stains."

    From the George Eastman House, Notes on Photography.

  7. #7
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    I've not heard of using cyanide in fixing daguerreotypes. Do you have any documentation of its use in the daguerreotype process? As previously noted, it was (and still is) the preferred method of fixing wet collodion images.

  8. #8

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    and its washed right down the drain into the water supply

  9. #9
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    Cyanide breaks down into harmless components with strong sunlight (not instantly, but within a reasonable period of time - days I believe), and these days, with the small volume of wet-plate photographers today, it is so diluted in city sewage systems that it is a non-issue, unless you have a neighbor drinking from your unfiltered outflow. Frankly, I'd be much more concerned with the prescription drug residue in the water supply than I would effluent from a wet collodion enthusiast or two.

  10. #10

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    Quote Originally Posted by TheFlyingCamera View Post
    I've not heard of using cyanide in fixing daguerreotypes. Do you have any documentation of its use in the daguerreotype process? As previously noted, it was (and still is) the preferred method of fixing wet collodion images.
    Not used for fixing or developing, but was sometimes used in the process for silver-plating the dag plates.

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