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  1. #11

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    H&W Control
    This developer, invented by Harold Holden and Arnold Weichert in the late 1960's, was patented in 1973. The patent has expired, and the formula is now in the public domain.
    H&W Control was sold in retail stores for several years, but did not receive widespread distribution. Before being commercialized, it was used extensively by the US military for developing surveillance films, the kinds used by top-secret high-altitude aircraft of the day such as the U2.

    The developer recipe listed below is my TEA version of H&W Control, formulated for multi-year shelf life. This modified H&W Control formula should give you similar sensitometric results to those obtained with commercially packaged Bluefire HR.
    Solution A:
    Triethanolamine 75 ml
    Hydroquinone 0.32 g
    Phenidone 2.2 g
    Triethanolamine to 100 ml


    Solution B
    Water 750 ml
    Sodium sulfite 4.5 g
    Sodium carbonate 2.3 g
    Water to 1 liter

    Add 25 ml Solution A to 250 ml Solution B, then add water to make 1 liter of Working Solution.

    Phenidone and Hydroquinone are soluble in TEA. Warm the Triethanolamine to 80° to 100°F in a water bath. Then mix the chemicals in the order shown, and be sure each is completely dissolved before adding the next.

    Use with Bluefire Police, Agfa and Fuji microfilms, and Kodak Technical Pan. Gives unacceptably flat images on ordinary films.

    Shelf life of solution A is expected to be very long (years).
    Shelf life of solution B is expected to be 2-3 years.
    Last edited by Tom Hoskinson; 04-24-2008 at 04:33 PM. Click to view previous post history. Reason: grammar
    Tom Hoskinson
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  2. #12

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    Nov 2004
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    Looks promising,Tom.
    My H&W Control went off after about 6 months.
    Copex Rapid,EI 25, sun/shade, 14 min 68F in H&W Control.

  3. #13
    Murray Kelly's Avatar
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    I took the BF HR control packet (the smaller one) and disolved the contents in denatured alcohol. Any sulfite there is pretty insignificant and I stir well before drawing off the amount I need with a syringe. I don't believe there is enough there to make any difference, really, but do it anyway. It just disappears into the final mix.

    My separate stocks are still fine a year later. FF label them 'B' for the active ingredients and 'A' for the activator / sulfite powder, IIRC? The opposite to what I'm used to anyway. As I say - it's been a year.

    Murray

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