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  1. #11
    Ole
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    Quote Originally Posted by chuck94022
    Is this what J and C does?
    As far as I know it's partly what J&C does in companionship with Fotoimpex. It is also what MACO, Bergger and several others do.

    Fotokemika does a lot of that work (think EFKE/ADOX and RolleiR3), as does Forte. There is also Slavich in the FSU who will coat any emulsion on any substrate, if the order is large enough. If you want 20x24" orthopanchromatic glass plates, they're the ones to ask.
    -- Ole Tjugen, Luddite Elitist
    Norway

  2. #12

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    I think Kodak still sells glass plates (Timex 100) for scientific and industrial uses. Expensive but available by speical order. I would guess that plates are available in China, Russia, and Japan for the same reasons. But for 20XI24, they would be very expensive. Making plates at home, because of the toxic materials (at least in Arizona) you would need a permit for industrial use. The police will think you are making crank.

    Paul

  3. #13
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    Jim Browning makes his own emulsion and has coated it. See his web site for the excellent details that he has posted there for doing this. He now has matrix film made for him at the Efke plant. So, yes, this is a way to go to get custom products.

    If your homemade film or paper cracks, add some sorbitol to the mixture. This is a common humectant used in making film and paper to prevent or minimize cracking and crazing.

    The biggest problem you will ever have if you make your own film or paper is coating it uniformly enough to make a good quality material. I see a similar discussion going on over on photo.net. Good luck to you all.

    PE

  4. #14
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    Emulsion making in concept is fairly easy. In practice, however, it is an incredibly complex undertaking.

    First off, you have the gelatin. It has to meet certain standards of purity -- meaning it can't have the wrong impurities, but it needs to have some of the right impurities. (Shortly after Eastman started manufacturing dry plates, he had a large batch fail. Investigation traced it back to the sulfur content of that batch of gelatin. This product failure played a large part in the formation of the Kodak Labs.)

    Once you have the gelatin, you have to very carefully and consistently add the other ingredients (i.e., the silver, the halide(s), the sensitizers, etc). Then you have to let the emulsion age for a period of time.

    Once it has aged, it has to be allowed to solidify. It is then shredded and carefully and thoroughly washed to remove all of the excess and byproduct chemicals.

    Then you get into coating...

    While much of the basic science of emulsion making is quite well documented in the literature, there is a great deal of proprietary, unpublished knowledge involved as well. Kenneth Mees addressed this in the preface to his book "The Theory of Photography" saying that he had to basically ignore that whole aspect of the science because much of his knowledge of it was acquired via his work for Eastman and was therefore nondisclosable.

    I have a great fear that, because so much of this is proprietary, it will be "lost" information should the major manufacturers cease manufacturing film.

  5. #15

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    Actually I used to work with just two other people and we made cars. High performance racing late model stock cars and scca prototypes. And I did so much of it for a couple of years that I could probably due my aspect of production blindfolded.

    As I stated in other posts you have to stop looking at the idea of creating film and emulsions through the eyes of Kodak. For some reason in America today we become hypnotized by the idea that there is only one way to do something, or only a big company can do it. I am not a scientist but i know that somewhere there is going to be simpler chemistry, process and technology to make quality film in small quantities. You have to think outside the box of the current film production paradigm. The biggest thing you need to understand is that Kodak needs to make millions of $ and has to produce film by the millions of feet at a certain cost to produce a profit. Get that concept out of your head and start thinking minimum parameters for small batch coating. Say 100 sheets of 8x10 or equivalent roll at a time.
    I am sure that many of the steps, chemistry, etc that Kodak uses to make TriX are probably totally irellevant when talking small batches but required when producing millions of feet that has to stay fresh for several years.
    "Fundamentally I think we need to rediscover a non-ironic world"
    Robert Adams

  6. #16
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    I agree with Jim. Making an emulsion need not be as complex as it is to produce a Kodak or Fuji film. It can be simple and probably can perform in a suitable manner for many applications. Matthew Brady didn't have Kodak film and made some beautiful photographs.

    If you read the literature, there are hundreds of steps involved in making an emulsion, and it takes weeks or months to produce the film and paper we use.

    PE

  7. #17
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    Quote Originally Posted by Jorge
    but heck, if it was good enough for G. Eastman, it might just be good enough for us...
    It wasn't good enough for George Eastman. That's why he invented film, the key to the success of the Brownie camera.

  8. #18

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    Quote Originally Posted by c6h6o3
    It wasn't good enough for George Eastman. That's why he invented film, the key to the success of the Brownie camera.
    He started Kodak making glass plates, this was limited to LF cameras and his purpose was to bring photography to everbody, thus the research and eventual process of coating acetate cellulose. Coating either one is very similar, glass plates were good enough to get him started and produce good quality negatives (as a matter of fact they are better than acetate film for definition or resolution) but could not be rolled or made in smaller sizes for smaller cameras.

  9. #19
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    Well, the good news is in 20 years when there are no more mechanical shutters and the ones we have now are shot, we'll be coating our own glass plates with asa 3 goop and won't need a shutter anyways. I'm ahead of the curve having worked with Freestyle APHS Ortho for several years now. Sign up for my ASA 3 Ortho Workshop. Just kidding.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

    http://tonopahpictures.0catch.com

  10. #20
    Ole
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    Jim, one of my mechanical shutters is still precise - and it was made in 1926. I think it will outlast me too.
    -- Ole Tjugen, Luddite Elitist
    Norway

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