expired d76

Discussion in 'Black and White' started by bruce_erickson|1, May 5, 2013.

  1. I think it was just the order in which Kodak's lab techs came up with the formula.
    D-1 was probably a Pyro-Soda mix concocted in the 1870s. D-19, IIRC is a Hydroquinone-caustic high-contrast developer for processing lith film.

    Looking back, I find it amusing how much time and effort was put into seeking a holy grail of a developer. That elusive (and probably non-existent) magic soup that gave full film speed, along with fine grain, high acutance and superb tonality.

    Jeez guys; why not just stop when you got to number 76? It's about as good as you're going to get.
     
  2. I suppose so. But if you have a lab full of chemists, they can probably try hundreds of them a day.
    But, then, the numbers should be in the thousands or tens of thousands.

    So it isn't all the formulae that they came up with, but only the ones that were good enough.
    But if they were good enough, why don't we hear about them.

    I think when I was young, I thought D-76 was related to 1776, one country's favorite year.
    Even more, my first tank and trays were named Yankee, and the trays are red, white, and blue.

    (I still have my original 5x7 and 8x10 trays from over 50 years ago. Not so many years ago,
    I got a set of Yankee 11x14 trays.)
     
  3. You think?
    I'm sure you're overestimating the number of research chemist's employed, and underestimating how long it takes to fully characterise a new developer. Plus there's the production cost v benefit to consider, as well as whether there's any actual need or demand for yet another fairly random combination of reducing agent, alkali accelerator, antioxidant and restrainer.

    It's a juggling act with a fairly limited set of balls and throwing patterns!

    And my first developing tank was plain black bakelite and branded 'Nebro', which I later came to know was a company founded by a chap named Neville Brown.
     
    Last edited: Sep 20, 2021
  4. Polystyrene is so much nicer. I think I never had a bakelite tank.

    Reminds me, though, of one my grandfather had that I also didn't inherit, which
    worked up to, as well as I remember, 122. It had different spacers that you put
    either between the reel halves, or outside, to get all the combinations needed.

    But now you don't find tanks up to 122.

    You should be able to parallel process different developer combinations, and also
    parallel characterize them. Well, maybe sequential characterize, but still do
    it pretty fast.

    The only number I know by number, is that the drug RU486 is named
    after being the 30,486th try.

    But otherwise, it does seem like we give different developers
    more magical properties than we should.
     
  5. Just a very minor point of order.
    The dates on developer, films, etc are when they become "outdated". The thingie only "expires" when it no longer works.

    NTIM, but things can continue to work, even if a little awkwardly, sometimes for decades after the "use before" date.
     
  6. Then you've not experienced the peculiar, yet not unpleasant, smell emitted by a bakelite tank in contact with developer. "A la recherche du temps perdu."
     
  7. I guess not.

    It reminds me, though, of the unique smell of roll film backing paper, which I had almost
    forgotten but not quite, after so many years. It is especially interesting that there is something
    volatile enough to smell, yet doesn't affect the film over many years. Maybe it is just the
    Kodak backing paper smell.

    But if I found a 122 tank for a good price, I might buy one, and likely it would be bakelite.
     
  8. I haven't thought about Bakelite for a while, so was reading the Wikipedia article about it. It seems that Baekeland is also the inventor of Velox. I remember Kodak Velox, but I suspect, like many others, that it was bought by Kodak and then kept its name. It was the first paper that I used, though not so much after I got an enlarger. In any case, since it is a phenolic compound, I will guess that the smell is phenol related. That is also the smell we usually note for burning electronic equipment, as they have, or at least used to have, enough phenolic parts. Among others, popular for cheaper (than epoxy glass) printed circuit boards.
     
  9. I don't know how much that package would cost today but back in the late 70's when I did some B&W it was very cheap. I would not use expired developer because films are too expensive now to risk using iffy developer.
     

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