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  1. #11

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    Quote Originally Posted by gainer
    Perhaps the biggest problem would be assuring that the metol and hydroquinone were both uniformly distributed in the mixture.
    What you need is a "ball mill".

    Throw a dozen large steel balls in the container (hopefully it is not glass or thin plastic) and roll it around for some time to let the balls break the crystals into smaller crystals and powder them.

    Use a rock polisher if you have access, or duct tape the container to the inside of the mag wheels of a friend's muscle car and drive around slowly for an hour. This will allow the steel balls to pulzerize the mixture and mix it until it becomes homogeneous.

  2. #12
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    Quote Originally Posted by Donald Qualls
    Gadget, I'm pretty sure 777 isn't fast working enough to make a monobath with rapid fixer. HC-110 Dilution A is barely fast enough, with the rapid fixer diluted at 1:24 (normal film strength is 1:4).
    That being the case, you can probably use the fixer, developer and all, as fixer. I say this because I often add fixer concentrate directly to the developer at the end of development time. Even TF4 acts as stop bath and fixer when I add at least 1 ounce of fixer concentrate for every ounce of developer. Edwal used to suggest this method of using their rapid fix, and I did it then and still do. I think in some cases the timing of development is more consistent than if I poured out the developer, poured in stop bath or water, poured that out and then poured in the diluted developer.
    Gadget Gainer

  3. #13

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    Quote Originally Posted by jdef
    I've used my blender to powder sugar, and grind coffee. Might work.
    THis would work, but I would dedicate that blender to only be used with chemicals, and not coffee. Perhaps you local thrift store has some real cheap.

  4. #14

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    Hi there,

    Commercial Developer Kodak DK - 50

    Water (125°) 500ml
    Elon (metol) 2.5g
    Sodium Sulfite 30.0g
    Hydroquinone 2.5g
    Kodalk 10.0g
    Potassium Bromide 0.5g
    Water to make 1.0L

    Dissolve in order given.
    Suggested: 4 - 6 min.@68°F in trays
    8 min.@68°F in tanks
    8 min.@68°F in tanks at 1 -1 for portraits


    Commercial Developer Kodak DK - 60a

    Water (125°F) 750ml
    Elon (metol) 2.5g
    Sodium Sulfite 50.0g
    Hydroquinone 2.5g
    Kodalk 20.0g
    Potassium Bromide 0.5g
    Water to make 1.0L

    Dissolve in order given.
    Suggested: deep tank = 7 min.@68°F

    You could always mix it up as divided D-76. DK50 & DK60 are both very fast acting, dilute 1-1.

    Just a thought.

  5. #15
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    Quote Originally Posted by Kirk Keyes
    THis would work, but I would dedicate that blender to only be used with chemicals, and not coffee. Perhaps you local thrift store has some real cheap.
    I have in fact seen small blender-type coffee grinders at low cost. Walmart probably has one. That might be a good thing to have for dedicated use in the darkroom. I don't think much of coffee ground that way.

    One problem with this method of mixing is that air is entrapped in the powder, which probably increases the oxygen diaaolved in the developer solution. This initially dissolved air may be more than can be absorbed by opening and pouring from the developer bottle, whether you use marbles or a collapsible bag or other means of keeping air from the surface of the stored developer. It is always recommended that water to be used for making developer solutions be boiled to eliminate as much air as possible, but I think a vacuum pump would be needed to get it out of powdered solids. IIRC, one of the reasons for premature failure of XTOL was leaking "vacuum sealed" foil pouches.
    Gadget Gainer

  6. #16

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    Quote Originally Posted by gainer
    One problem with this method of mixing is that air is entrapped in the powder, which probably increases the oxygen dissolved in the developer solution.
    Yes, quite probably.

    But think about how many grams of oxygen that would be. One mole of air at STP will occupy about 22.4 liters and weigh about 29 grams. That's a little over 1 gram/L.

    So how much air will be trapped in that 5 grams of powder that you are going to measure out? Let's be generous and say maybe 1 ml of entrapped air? So that's about 1 mg of air. And then only 21% of that air is oxygen, so now we are down to about 0.2 mg of oxygen that would be entrapped. But I don't think I would call this a problem.

  7. #17

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    Quote Originally Posted by Donald Qualls
    Gadget, I'm pretty sure 777 isn't fast working enough to make a monobath with rapid fixer. HC-110 Dilution A is barely fast enough, with the rapid fixer diluted at 1:24 (normal film strength is 1:4).
    At 80F it might be. Wonderful things happen with 777 @ 80 degrees.

    tim in san jose
    Where ever you are, there you be.

  8. #18
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    Yes, it is true that the amount of air would be very small, but so is the amount of air that we worry about so much that we fill airspace with marbles or use wine bags. One molecule of oxygen can and will disable one molecule of ascorbic acid. I wouldn't hesitate to use the pulverizing mixer, but I won't make any guarantees about it to others until after I have tried it.
    Gadget Gainer

  9. #19
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    (re: 777 accidentally mixed with rapid fixer as a monobath)

    Quote Originally Posted by k_jupiter
    At 80F it might be. Wonderful things happen with 777 @ 80 degrees.
    My experience (having actually made a monobath with rapid fixer) is that there are very, very few commercial developers fast enough working for this to be practical. My own monobath requires HC-110 Dilution A, at 75 F, which would normally give a development time of not much over two minutes, and at that I had to boost the alkalinity and dilute the fixer as far as I dared. My monobath formula is reproduced in an article on APUG about a Pintoid Processor (the article isn't mine, but the monobath is). Take a look over there and tell me if 777 would work fast enough, even at 80 F, to beat a fixer that takes less than six minutes to fully fix the film.

    Even if it can, you'd have to replace the alkali neutralized by reaction with the acetic acid in the fixer, and the fixer is so dilute it should be used as one-shot -- which rather defeats the reusability of 777.
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  10. #20
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    Jay, your Rapid Universal Developer is the first one I've seen that was a good candidate for monobath use with rapid fixer at common film strength -- complete dev and fix in three minutes, looks like, and hang the film less than ten minutes after pouring the soup. If you already have an alkaline rapid fixer on hand, I'd suggest trying it. You might have to adjust alkalinity or dev/fixer ratio to get the right contrast, and since the fixer is removing the halide even as the developer is reducing the exposed portion, there is usually some loss of film speed -- but the press used to love monobaths before Polaroid and then digital took over their rapid-pub applications. Develop 35 mm film inside the cassette, in daylight, in a coffee cup, using a pencil (eraser end) to manipulate the cassette spool by way of agitation. Even traditional monobaths worked in ten minutes or so, and with RUD-based monobath, if you have a way to wet-scan the negatives, you could shoot film and seriously compete with Polaroid and digital...
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

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