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  1. #21
    Jon King's Avatar
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    Donald Qualls (he's here on apug) came up with a monobath formulation using HC-110, and Ilford Rapid fixer, and household ammonia. He originally posted it on photo.net, and I referenced it in an 'pintoid' camera article here on apug in the how to article section.

    It works. My negatives were printable, but a bit low in contrast. I plan to experiment with the developer as a winter darkroom project to see if it can be optimized. I don't know if he has any refinements to it.
    Jonathan
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  2. #22

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    See if you can locate a copy of Grant Haist's Monobath Manual.

    One of the problems with monobaths is that they must be fine-tuned for each particular film. For example, a monobath created for Plus-X need not work well with Tri-X. This in part negates their usefullness.

    Another problem is that the rated film speed for a film is usually not the same when developed in a monobath as opposed to a conventional developer. Plus-X could be faster than Tri-X.

    Most of the useful monobaths use hard to obtain and possibly dangerous ingredients.

  3. #23
    David A. Goldfarb's Avatar
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    I've done what Ole mentions, and Patrick Gainer discusses in other threads--just killing the developer with rapid fixer concentrate. It works pretty well, particularly if you use a dilute developer that oxidizes quickly like PMK, but who knows what the archival properties of such negs would be.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com

  4. #24
    Ian Grant's Avatar
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    In the 70's I did a lot of commercial research into Monobaths.

    Have look in old British Journal of Photography Annuals, early 70's, Geoffrey Crawley wrote an article . I must still have it somewhere.

    Our research was on monobaths for print processing, but for films would have been only slightly different in formulae. Particularly as the emulsion under test was a Silver Bromide/Iodide composition which we'd evolved and manufactured in-house.

    If the formula was balanced correctly results quality wise and longevity were no different to normal processing.

    Ian

  5. #25
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    Just FYI, D76 is a monobath for all practical purposes for some B&W papers, if they are high chloride. The paper loses a lot of speed, but develops a nice image and is fixed out in about 3 - 5 minutes in D76 with no fuss.

    Interesting, but probably of no use to anyone unless you like to play around.

    PE

  6. #26
    gainer's Avatar
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    Quote Originally Posted by David A. Goldfarb
    I've done what Ole mentions, and Patrick Gainer discusses in other threads--just killing the developer with rapid fixer concentrate. It works pretty well, particularly if you use a dilute developer that oxidizes quickly like PMK, but who knows what the archival properties of such negs would be.
    I cannot see how this method could have any effect on archival qualities. It simply dissolves the halide as any other fixer. The rest depends on the washing. The result of adding fixer to developer is to form an alkaline fixer, usually. If an alkaline concentrate such as TF4 is used, the result will certainly be an alkaline fixer. Aren't these supposed to be more easily washed out?
    Gadget Gainer

  7. #27
    Ian Grant's Avatar
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    Monobath Formula

    FX-6a (G Crawley)

    Sodiun Sulphite (anhyd) 50gms
    Hydroquinone 12gms
    Phenidone 1gm
    Sodium Hydroxide 10gms
    Sodium Thiosulphate 90gms
    Water to I litre

    The Thiosulphate can be varied betweeen 70gms to 125gms to alter sftness, and increasing Hydroquinone to 15 - 17 gms will increase the contrast. Crawley states that this formula gives normal film speeds, processing is normally around 4 to 5 mins at 20°C
    and between 9 - 12 films per litre capacity.

    See British Journal of Photography Annual 1972, page 162, article: Rise and Fall of the Monobath, also page 231 for details of how to use the Monobath

  8. #28

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    Two-bath monobaths are not true monobaths. The addition of the fixer concentrate merely stops and fixes the film as in any ordinary B&W process. For a monobath processed negative the bulk of the silver is concentrated near the surface of the emulsion. If you should look a two-bath monobath negative it would look like a conventional negative with the silver distributed throughout the emulsion.

    Anyone wishing to experiment with monobaths should read Haist's book. This is the bible on the subject.

  9. #29
    Ian Grant's Avatar
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    Gerald, am I right in assuming Crawley's referance to the Monbath Manual, by Grout Haist in the 1972 BJP Annual is a Typo for Grant Haist, when was the book published, and rather was it revised after 1972.

    Not quite sure about your referance to Two bath monobaths, Crawley does indicate that FX-6a can be made up and stored in two parts before use. But it's a obviously a true monobath when mixed for use.

    Ian

  10. #30

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    Yes you are correct about the typo for Grant Haist. The monobath Manual is a great book and while fairly slim summarized monobath development at the time of publication. AFAIK, interest in monobaths soon faded after publication because of the difficulty in a producing a bath which would work with any film.

    I was commenting on Ole's post in which he says "... I've turned to "two-bath monobaths" - single shot developer, pour in a dash of rapid fixer concentrate at the end of development." While this may work it is not a monobath and will not produce the same results as a monobath.

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