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  1. #31

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    More on the Wine Please...

    Perhpas because I'm a tea-drinking Brit coffee really doesn't excite me. But the idea of developing in red wine is so outragous that, if it can be done, I have a sudden urge (no doubt in part due to the wine I've just drunk) to try it. So can it really be done, has anyone done it, should I add some washing soda? Anyone help me start? I have a third of a bottle of wine sitting beside me that my liver would thank me for not finishing...

    Hywel

  2. #32
    titrisol's Avatar
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    I think that experiment was already done, search in the archives during the winter of 2004

    Caffeic acid can be horribly expensive yes, that is why is more convenient to use instant caffe!
    Mint works great, but you need lots of leaves to make a developer.

    Run a google of coffe developer RIT or mint developer RIT


    Quote Originally Posted by rwyoung View Post
    I do believe it is the caffeic acid that is doing the majority of the work. Caffeic acid is a phenol and is relatively similar to catechol and hydroquinone but with a few extra bits and its OH pairs aligned a little bit differently. Coffee in general is quite a witches brew of phenols!

    I think caffeic acid is still present in decaf coffee, need to get a small jar of instant decaf and try it.
    Mama took my APX away.....

  3. #33
    Dave Swinnard's Avatar
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    Yup, it works.

    I tried the caffenol recipe today at a student's request.

    HP5+ @ 200 for 35min about 68F (20C) with 10 sec. agitation every minute or so (mostly so, as I kept getting pulled away to attend other things...)

    Image is certainly present but is heavily stained, low contrast but with adequate shadow details. I hope to try and print it tonight.

    Maxwell House instant and a "super" washing soda with the Arm & Hammer logo. (I think "super" means it had something a bit "perfumed" in it.)

    Cool

    Dave

  4. #34

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    Quote Originally Posted by Jordan View Post
    There are only three possible configurations of dihydroxybenzene: 1,2-dihydroxybenzene (catechol), 1,3 (resorcinol) and 1,4 (hydroquinone). Of these three, only resorcinol is not active as a developing agent (it can't form quinones as the electrons don't "push" the right way). Caffeic acid is in fact a catechol -- its hydroxy groups are in the 1 and 2 positions on the ring -- it also has an acrylic acid substituent elsewhere on the ring that is not terribly photographically active.

    I'm thinking of ways to make caffeic acid in the lab, and while it's a somewhat simple molecule, the "hookup" of its structure would make it take a couple of steps -- hence the price.
    I've read that coffee (both instant and brewed) contains both caffeic acid and oxalic acid. Oxalic acid has a long history as a developing agent. I wonder if anyone has done comparative testing? Maybe Folgers Instant vs Starbucks brewed?
    Tom Hoskinson
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  5. #35
    David A. Goldfarb's Avatar
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    Yes, if you go to the paper I linked above, it says what the concentration of Oxalic acid is as well.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
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  6. #36

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    Quote Originally Posted by David A. Goldfarb View Post
    Yes, if you go to the paper I linked above, it says what the concentration of Oxalic acid is as well.
    Yes David, your link is the reference I had in mind.
    Tom Hoskinson
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  7. #37

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    developing with mint, thyme, and basil

    Quote Originally Posted by laverdure View Post
    When I was playing around with coffee last year, my more organic chemistry minded friend came to believe it was the phenols which were the primary developing agent. Based on that assumption, we got mint, thyme, and basil to work, before we read elsewhere that it'd been done. I was just messing around, but I hear that mint works much better than coffee.
    Hi laverdure, those sound like good experiments, can you please post details on how you used the mint?

    did you arrive at a formula that worked well? or can you give any starting points?

    cheers

    pete

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