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  1. #31

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    One thing I have noticed when experimenting with using coffee as a developer was that it did not work so well on Agfa MCP 312 RC. My original work was done on Ilford Multi-Grade Cool Tone Paper, which showed better image formation with just coffee. Both papers did develop good images once the ascorbic and phenidone were added.

    I was reading another thread about using Tylenol and I saw a comment about newer papers(specifically Ilford Multigrade) including a develop agent in the emulsion.

    I decided to test whether the image formation I was seeing was really the incorporated develop agents. I exposed a negative that I had worked with recently on both the Agfa MCP 312 and the Ilford Mulitgrade Cool Tone and developed for one minute in a strong alkali solution of Sodium and Potassium Hydroxide. Both papers showed an image, but the result on the Agfa paper was very faint, whereas the Ilford paper had a pretty strong image with no solid blacks and some fogging.I tried this again with just the Ilford paper after adding some coffee to the developer. The result was very similar but there was a very slight brown tone. This is similar to what I see with just accelerator and coffee.

    This leads me to believe that the coffee isn't doing much at all, and the incorporated develop agent in conjunction with the ascorbic acid/phenidone combo is doing all the work. When I started my experimentation it was just as the Agfa paper was becoming unavailable, so I was in the process of switching to Ilford. I had noted a faster develop rate from the ascorbic acid/phenidone developer, but I think this was really due to the Ilford paper responding to the accelerator in the solution better than the Agfa paper.

    The only thing that the coffee does seem to do is add some tone particularly if the paper is left in the developer for longer than 2 minutes, and at higher temperatures. Since Ilford Cool Tone paper needs the longer develop times to achieve deep blacks this works well to get cold whites with warmer greys. The only thing I still have to validate is whether the coffee is really helping to preserve the solution any.


    -nsp

  2. #32
    Donald Qualls's Avatar
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    I can't talk about developing paper in coffee or acetaminophen-derived p-aminophenol developers since, with about 85% of a five gallon box of Dektol to use up, I'm staying orthodox with my prints, but *film* has no incorporated developing agents -- and I routinely develop films of a couple varieties in both Caffenol and Parodinal.

    Fomapan 100, aka Arista.EDU Ultra 100, processes well in Caffenol, though it seems to give little stain; Tri-X 35 mm looks very grainy in a scan after Caffenol processing, but the stain image masks the grain and can produce 8x10 prints from 35 mm that show no visible grain. I haven't yet tried Classic 400, aka Fortepan, in Caffenol, but it works very well indeed in Parodinal (as does .EDU Ultra/Fomapan 100) -- for that matter, so does Tri-X, though I don't know that I'd want to put 35 mm Tri-X in Parodinal.

    NONE of these good to excellent results can be due simply to the alkali reacting with "stuff" already in the film -- they can only result from actual developing agents in the developers.

    FWIW, when I've read about coffee developer for paper, ISTM they talked about it being very slow (as it is with film); you might try a non-DI paper (like, say, Forte Elegance FB) with dev times allowed to run as high as ten minutes, to see what you get.
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  3. #33

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    Quote Originally Posted by Donald Qualls
    I can't talk about developing paper in coffee or acetaminophen-derived p-aminophenol developers since, with about 85% of a five gallon box of Dektol to use up, I'm staying orthodox with my prints, but *film* has no incorporated developing agents -- and I routinely develop films of a couple varieties in both Caffenol and Parodinal.

    Fomapan 100, aka Arista.EDU Ultra 100, processes well in Caffenol, though it seems to give little stain; Tri-X 35 mm looks very grainy in a scan after Caffenol processing, but the stain image masks the grain and can produce 8x10 prints from 35 mm that show no visible grain. I haven't yet tried Classic 400, aka Fortepan, in Caffenol, but it works very well indeed in Parodinal (as does .EDU Ultra/Fomapan 100) -- for that matter, so does Tri-X, though I don't know that I'd want to put 35 mm Tri-X in Parodinal.

    NONE of these good to excellent results can be due simply to the alkali reacting with "stuff" already in the film -- they can only result from actual developing agents in the developers.

    FWIW, when I've read about coffee developer for paper, ISTM they talked about it being very slow (as it is with film); you might try a non-DI paper (like, say, Forte Elegance FB) with dev times allowed to run as high as ten minutes, to see what you get.

    For film what kind of develop times are required with caffenol?

  4. #34
    Donald Qualls's Avatar
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    Quote Originally Posted by nspatel
    For film what kind of develop times are required with caffenol?
    For Plus-X, about 25 minutes, for Tri-X and Fomapan 100, about 30 minutes -- this is at 68-70 F, with agitation ten seconds out of each minute.

    You can cut this by more than half by adding 1/4 g of ascorbic acid and an additional 1/2 tsp washing soda to each 8 ounces of developer; the resulting Caffenol C gets the job done in about 12 minutes, but gives effectively no stain; my suspicion is that the vitamin C is doing effectively all the work at this strength.
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  5. #35

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    Quote Originally Posted by Donald Qualls
    the resulting Caffenol C gets the job done in about 12 minutes, but gives effectively no stain; my suspicion is that the vitamin C is doing effectively all the work at this strength.
    Maybe yes, maybe no. Remember ascorbic acid is also an antioxidant like sodium sulfite. Addition of sufficient sulfite to a staining developer will also prevent the stain from forming.

  6. #36
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    That is something I didn;t know!
    The stain with Caffenol C is much lighter than without C.
    But also the shadow details gets a nice boost with C
    Mama took my APX away.....

  7. #37
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    Quote Originally Posted by Gerald Koch
    Maybe yes, maybe no. Remember ascorbic acid is also an antioxidant like sodium sulfite. Addition of sufficient sulfite to a staining developer will also prevent the stain from forming.
    True, but adding a bunch of sulfite to Caffenol won't speed it up by more than a factor of two; the only way to be reasonably sure would be to make the same developer (to the same pH, which would require slightly less carbonate) without the coffee (and another without the ascorbate) and see what it does. It'd be a pretty darned simple developer, just ascorbic acid and sodium carbonate in water; don't expect it to last, but it should be easy enough to mix it on the spot since both ingredients are very soluble at these concentrations.

    Hmmm. I might have to try that, if I can find a way to test the pH (pool test kits won't handle the level of alkalinity for developers, I don't think, and pH papers are relatively expensive for the limited use I'd get from them). It'd settle for me, once and for all, whether it's superadditivity, plain additivity, or just the ascorbate taking over the whole job.

    Oh, hell -- I'd need a densitometer, too, to measure and control the contrast and evaluate the densities, unless I could calibrate and control my scanner to do that job.
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  8. #38

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    Quote Originally Posted by Gerald Koch
    Maybe yes, maybe no. Remember ascorbic acid is also an antioxidant like sodium sulfite. Addition of sufficient sulfite to a staining developer will also prevent the stain from forming.

    I didn't realize that antioxidants will curb staining. I thought that the reduced stain after adding ascorbic acid was simply because the total develop time was less. This makes a little more sense. For paper I have tried a 2 bath approach. The first was a caffenol and the second was a low pH ascorbic acid/phenidone bath. After developing for 3-4 min in each bath I got prints with a lot of brown tone. Way more than if I develop a print for 3-4 minutes in a Caffenol/Vit C developer.

  9. #39
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    Quote Originally Posted by nspatel
    I didn't realize that antioxidants will curb staining. I thought that the reduced stain after adding ascorbic acid was simply because the total develop time was less.
    I'm inclined to think both are involved in this; I still get mild stain with shorter develop times and much weaker solution in Caffenol LC (for pictorial contrast on microfilms), but I see nothing I can identify as stain, even with a color scan and examination of the color channels (closest thing I have to a color densitometer), when using Caffenol C or Caffenol LC+C.

    Also, I've heard several opinions that too much sulfite will reduce staining in pyro and pyrocat developers; also that hydroquinone is a staining developer in the absence of a preservative like sulfite or ascorbate (you can make a very, very simple staining developer with nothing more than hydroquinone and sodium carbonate).
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  10. #40

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    Color negative developers are similar to staining developers in that too much sulfite prevents the formation of an image. Some sulfite must be in the developer in order for it to keep. However, the sulfite content must be keep low, 4 to 6 grams per liter in order achieve sufficient density. A similar low concentration of sulfite is required for pyro developers.

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