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  1. #1

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    Ascorbic acid (only) developer

    Has anyone ever put together a fine grain developer based on ascorbic acid alone? Think something like XTOL but with more isoascorbate, no Phenidone, and a stronger alkali like maybe sodium carbonate instead of Sodium metaborate. Presumably it would require long development times, but I've never seen that as a drawback if image quality can be improved. I guess film speed would be reduced. Would a long development time necessarily mean higher fog?

    Anyhow just thinking out loud. Actually as I write this I'm realizing an ascorbic acid-carbonate developer might essentially be a Caffenol-type developer (since my understanding is ascorbic acid is likely responsible for most of the reducing action in caffenol anyway). But caffenol doesn't have sulfite, or a restrainer.

  2. #2
    desertrat's Avatar
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    My understanding is, ascorbic acid by itself will work if you use lots of sodium carbonate, but the developing time is very long, about half an hour, and the negatives are very grainy and have developer fog.

    When I started making home brew developers about 10 years ago, I found a website that had a reprint of an old magazine article with directions for making this developer with vitamin C tablets and washing soda. It was presented mainly as a home experiment in using household ingredients to develop film.

    I followed the instructions, developed a roll of film for half an hour, and got the results mentioned above. The article warned the negatives would be grainy and fogged.
    Happiness is a load of bulk chemicals, a handful of recipes, a brick of film and a box of paper. - desertrat

  3. #3

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    Yeah I guess that makes sense based on what I've read. I'm not a home-brew kind of guy anyway, but enjoy thinking about this stuff. Another idea I had was a Metol-Ascorbic acid-Metaborate developer that had a relatively low amount of sodium sulfite (just for preservative purposes) and sodium chloride for solvent effects.

  4. #4

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    Quote Originally Posted by Michael R 1974 View Post
    Another idea I had was a Metol-Ascorbic acid-Metaborate developer ...
    Look at Ryugi Suzuki's DS-12 developer formula.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  5. #5

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    Why not try making some PC-TEA?

  6. #6

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    Re DS-12, I think that's a more active (carbonate) high acutance developer though. I'm thinking of a softer working formula that would also be a solvent developer, but using sodium chloride for solvent effects.

    Re PC-TEA, I've never been clear on its working properties. It has no sulfite, yet Gainer claimed it to be extremely fine grained.
    Last edited by Michael R 1974; 09-13-2011 at 07:57 PM. Click to view previous post history.

  7. #7
    ruilourosa's Avatar
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    i Think you need to read stephen anchell books!

    Ascorbic acid will work like hidroquinone (more or less) and will not be a decent developer for transparencies, although you could get away developing paper, specially for special effects.

    sodium chloride could function as a silver solvent, Microdol, i think, was based on this

    some time ago i saw a d-76 variant tha added 50gr of table salt to a liter of stock solution with 50% more time.
    i think fog will get in the way

    if you want soft images try parafenilenodiamine, the colour developer, try geoffrey crawley fx series, he made one for modern emulsions
    vive la resistance!

  8. #8

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    I've read Anchell/Troop to death. It's a good overview. There are plenty of developers, including pre-mixed commercial developers that do what I need. I was just thinking out loud about some things which, as pointed out in Anchell/Troop, have not been explored to any great extent because research stopped, like sodium chloride. It's in Microdol and Perceptol.

  9. #9
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    Ascorbic Acid isn't slow.. it depends on a lot of thing.

    I've used Asorbic Acid to make a contrast-stretching developer.

    I took 15 year old 500T film, which at normal processing, even pull processing gave very small dMax-dMin of even outdoor high contrast scenes, the developer I formulated gave huge dMax-dMin separation of even scenes that only had a 3 stop range (such as well lit indoors).

  10. #10

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    Quote Originally Posted by Michael R 1974 View Post
    Another idea I had was a Metol-Ascorbic acid-Metaborate developer that had a relatively low amount of sodium sulfite (just for preservative purposes) and sodium chloride for solvent effects.
    Michael, here's a formula you might be interested in.

    Isoascorbic Acid Developer

    Metol 2.5 g
    Isoascorbic acid 10.0
    Sodium metaborate 35.0 g
    Potassium bromide 1.0
    Distilled water to make 1.0 l

    Isoascorbic acid is also called erythorbic acid and is used extensively in food products.
    Ascorbic acid can probably be substituted.

    James, Vaneslow and Quirk: Phot. Soc. Amer. J1., 1953, 170-2
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

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