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  1. #21
    keithwms's Avatar
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    LOL I guess I'll just have to keep enjoying my nonsense then Leigh. The thing is, you probably never even tried it. If you had you wouldn't disagree with me, guaranteed.
    "Only dead fish follow the stream"

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  2. #22
    Leigh B's Avatar
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    Yes, I have tried it, with chemical analysis.

    It failed, which is why I don't do it.

    Amazing what science tells you that opinion hides.

    - Leigh
    “Wise men talk because they have something to say; fools, because they have to say something.” - Plato

  3. #23
    Roger Cole's Avatar
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    OTOH, others have tried it with film and got results they were happy with. It's amazing what application will tell you that analysis may not.

    I think the real lesson here is that most photo chemistry is pretty non-critical. Witness all the people who mix D23 using teaspoons and tablespoons to measure the sulphite and metol. It doesn't matter if they mix perfectly, or even particularly well; all that matters is that they mix well enough for results and repeatability that the user is happy with.

    So far, every single person who has posted about trying this with real film has reported good results. Has ANYONE here actually tried this, with film, and been unhappy with the results and consistency? Not analyzed the powder, not theorized, not worked it out mathematically, but simply mixed the powder as well as possible, mixed a partial batch, developed film with it, and compared the results to film developed by mixing an entire package?

    Personally it's cheap enough I'd rather just mix the whole thing and toss after a reasonable time, but not everyone wants to do that, or can afford to toss half a gallon of D76 worth $3 every six months. (Yes, that's some sarcasm, but I'm also serious about the fact that so far, every single user who has posted about trying this with film has been happy with the results.)

  4. #24
    keithwms's Avatar
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    What did you do Leigh, leave one side open for a day? Must have. I'd love to hear about your scientific method. My result is clear that it works well. P.S. don't presume to lecture me on science, it's what I get paid handsomely to do.
    "Only dead fish follow the stream"

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  5. #25

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    So how does baking a cake work then?

  6. #26
    Leigh B's Avatar
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    Quote Originally Posted by keithwms View Post
    I'd love to hear about your scientific method.
    My wife is a Ph.D. bio-chemist. At the time, she had a very well-equipped analytical lab.

    I mixed up a package of commercial developer, then gave her a sample of it (maybe 10%) and
    asked if the important ingredients were in the same proportion as in the original batch.
    They were not.

    I believe she used gas chromatography for the analysis.
    I don't remember the details since this was >40 years ago.

    Glad you make a good living. So does she.

    - Leigh
    “Wise men talk because they have something to say; fools, because they have to say something.” - Plato

  7. #27

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    First off, I agree with Leigh.
    Mixing part of a bag will not give you the exact same proportions as mixing the whole bag.
    However if the bag, jar, can or whatever it is shaken well (back and forth, upside down etc) each time before taking out the amount you need it will work. YES the proportions will vary slightly but it the final mix will me no more worse then making too much to start and trying to use a half bottle of mixed chemistry a year later.

    Also I am a Chemist working in a modern lab with over a million dollars of new top of the line gas chromatography, HPLC, Mass Spec etc equipment at my disposal. There is NO way that I could test a full bag of chemistry and a part mixed bag of chemistry and tell you how they differ. It does not work like CSI. It can be done but it requires detailed and expensive methods. Yes, Kodak has those worked out but just to buy columns for a gas chromatography or HPLC machine will run you from $100s to thousands of dollars BEFORE you even start.

    Maybe you were very lucky and she had the perfect setup but I doubt it. I could do a quick and dirty test for you with what I have but I will not be able to assure my results.
    Last edited by brianmquinn; 02-02-2012 at 08:44 PM. Click to view previous post history.

  8. #28

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    I am wondering about something....

    I know Kodak had an issue with XTOL where imperfect sealing caused 1 liter bags to go bad prematurely.

    If one is buying a larger bag of developer, say D76, and opening it multiple times to take small portions out, how would one seal the bag sufficiently so that the powder does not go bad??

    Perhaps the imperfect balance of constituent chemicals aren't all THAT critical. But I am not sure if I'd take that chance. OP bought a huge bag but 1 gallon bag doesn't cost that much and once mixed, lasts 6 months. It's not enough for me to take that kind of chance with my negatives.
    Develop, stop, fix.... wait.... where's my film?

  9. #29
    Leigh B's Avatar
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    Quoting from the Acufine instruction sheet:

    "Never mix partial container quantities."

    Boldface in the original document. No other text in that document is presented in boldface.

    So it appears that you're possessed of knowledge superior to that of the manufacturers?
    Whence does this knowledge emanate?

    The fact that you've "done it for years", and are "satisfied with the results" is meaningless.

    On a less sarcastic note...

    One solution to the problem is to make up "stock" solutions.
    Mix the entire contents of the package very thoroughly with a smaller quantity of water, like one quart.
    Divide that quantity into four eight-ounce bottles, each completely filled.
    Use collapsible plastic bottles, or add marbles.
    For use, add eight ounces of stock solution to 24 ounces of water to make one quart of working developer.

    - Leigh
    “Wise men talk because they have something to say; fools, because they have to say something.” - Plato

  10. #30
    Roger Cole's Avatar
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    Quote Originally Posted by Leigh B View Post
    Quoting from the Acufine instruction sheet:

    "Never mix partial container quantities."

    Boldface in the original document. No other text in that document is presented in boldface.

    So it appears that you're possessed of knowledge superior to that of the manufacturers? Whence does this knowledge emanate?

    The fact that you've "done it for years", and are "satisfied with the results" is meaningless.

    On a less sarcastic note...

    One solution to the problem is to make up "stock" solutions.
    Mix the entire contents of the package very thoroughly with a smaller quantity of water, like one quart.
    Divide that quantity into four eight-ounce bottles, each completely filled. Use collapsible plastic bottles, or add marbles.
    For use, add eight ounces of stock solution to 24 ounces of water to make one quart of working developer.

    - Leigh
    It's far from meaningless that he's been doing it for years and is satisfied - it's the ultimate answer to the question, for him.

    Secondly Acufine is not D76. It could be harder to keep uniform.

    Thirdly, if I were a manufacturer, I'd try to discourage mixing smaller amounts too. Better for me if you mix the whole thing and throw half away and buy more.

    Fourthly, I don't personally do this. But I'm still looking for someone who has tried it and not been happy with the results on film.

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