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  1. #21

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    Quote Originally Posted by gainer View Post
    The mention of coffee and tea made me think. Just on a whim, I dumped a tablespoon of ground coffee and half a tablespoon of ascorbic acid in 100 ml of TEA and brewed it in the microwave. Added some to a little cold water (I should have filtered the grounds out) and it eventually blackened a film snip.
    This is interesting. Do you suppose there's any chance the TEA would improve the keeping qualities of the developing agents in the coffee, as it does for phenidone IIRC?

    PC-TEA is on my Things To Do In Copious Free Time list, so when I have the TEA on hand maybe I'll experiment with this combination too. I'd suggest calling it CTC (for Coffee/TEA/vitamin C, of course, but it also happens to be the name of a commercial processing method for tea (not TEA)).

    -NT

  2. #22

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    most world's supply of robusto coffee comes from vietnam these days.
    when i buy instant ( only for my developer ) i look for the cheepest stuff
    on the shelf! it works great
    im empty, good luck

  3. #23
    Aurum's Avatar
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    Quote Originally Posted by ntenny View Post
    This is interesting. Do you suppose there's any chance the TEA would improve the keeping qualities of the developing agents in the coffee, as it does for phenidone IIRC?

    PC-TEA is on my Things To Do In Copious Free Time list, so when I have the TEA on hand maybe I'll experiment with this combination too. I'd suggest calling it CTC (for Coffee/TEA/vitamin C, of course, but it also happens to be the name of a commercial processing method for tea (not TEA)).

    -NT

    By TEA I'm assuming you mean Triethanolamine rather than the extract of Camellia Sinensis favoured by the English.

    Though Come to think of it if I save up a pile of old teabags it might just work....... :rolleyes:
    Could our South African chums substitute Rooibos (Redbush) tea instead.

    I feel a bit of experimentation coming on
    "Flatter Me, and I May Not Believe You. Criticize Me, and I May Not like You. Ignore Me, and I May Not Forgive You. Encourage Me, and I Will Not Forget You."

  4. #24
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    Most things that will dissolve in either Propylene glycol or TEA will be better preserved from oxidation than in water because they don't ionize as they do in water. For that reason, TEA or glycol should only be used as a solvent for stock solutions that will be diluted with water for use. If the developer doesn't oxidize itelf in the presence of silvr halides, it won't reduce the halides to metallic silver. It may be that you will have to use the coffee extract as you would p-aminophenol, along with ascorbate or catechol or hydroquinone to get enough concentration in the stock. I'm not much inclined to try to perfect anything like it. A developer like Pyrocat PC or a simple P-C Carbonate, with the P being p-aminophenol from Tylenol, would be my idea of a better way to get a high quality developer I could still get if all the photo chemical suppliers were forced out of business, which, if it comes to pass, will more likely be caused by do-gooder laws forbidding sales to ordinary people than by lack of demand. Its also nice to know you can develop a roll with stuff you can get almost anywhere even after most people have gone to bed.

    If I do come up with something good in one of my whimsical moments, I will certainly spread the word. Don't let my preferences govern yours. The argument from authority is the weakest form of philosophical argument. Pretend you're from Missouri even if you're not.
    Gadget Gainer

  5. #25

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    Quote Originally Posted by gainer View Post
    Most things that will dissolve in either Propylene glycol or TEA will be better preserved from oxidation than in water because they don't ionize as they do in water. For that reason, TEA or glycol should only be used as a solvent for stock solutions that will be diluted with water for use. If the developer doesn't oxidize itelf in the presence of silvr halides, it won't reduce the halides to metallic silver.
    I'm glad I asked, because to my astonishment I actually understood the answer! :-)

    I'm not much inclined to try to perfect anything like it. A developer like Pyrocat PC or a simple P-C Carbonate, with the P being p-aminophenol from Tylenol, would be my idea of a better way <...>
    Living as I do on a septic system (and with a baby in the house), I'm attracted to the negligible toxicity of coffee developers. The p-aminophenol developers are probably septic-safe but not baby-safe, and I assume anything with "pyro" in the name is a deathtrap, right?

    Don't let my preferences govern yours. The argument from authority is the weakest form of philosophical argument. Pretend you're from Missouri even if you're not.
    As it happens, much of my family *is* from Missouri. Don't worry, I'm not looking for an argument from authority, but where other people know more than I do, I try to avoid reinventing the wheel. I have the chemistry competence of a developmentally disabled wombat, so I depend a lot on other people's brains in this area. :-)

    -NT

  6. #26
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    Hey, wombats are cool. Most of my family are...
    Murray

  7. #27
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    I, too, am on a septic system. The darkroom is on a separate tank. The grass is quite green around its field. I have a great grand daughter who is just old enough to get into things, but does not seem to want to put unfamiliar substances in her mouth. As I write this, I got a call from a high pressure salesman selling stuff to clean the petroleum out of my lines. Imagine that! Something that will clean the oil out of a septic system in West Virginia! When we want to drill a water well, we have to hire a water witch to find one that will bring up water. BTW, there is something to the art of water witching. The distribution of the local gravitational field is influenced by the presence of underground water holes, among other things. Water is more dense than petroleum.

    I'm not so sure coffee developer is any safer than catechol after it's been treated with lye, which I cannot buy at any local store.
    Gadget Gainer

  8. #28

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    g'day all, great info, thnx

    so, we can replace developer, both film and paper, with coffee and washing soda, can we replace fixer with a common household product?

    Ray

  9. #29

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    hi ray

    i wish we could!
    im empty, good luck

  10. #30

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    Thanks all. Has anyone tried to use coffee and soda crystals as a paper developer for lith prints? If so, please can I have a recipe...I'm using Fomatone FB warmtone paper and looking for a colder effect than that resulting from using LD20 paper developer, perhaps Dektol paper developer added too....thank you

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