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  1. #11
    gainer's Avatar
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    Quote Originally Posted by jim appleyard View Post
    While you can use Vit. C for developing, it may leave a precipitate. This leads me to believe that by not dissolving completely, your dev isn't as efficient as it could be.

    Go with Pat Gainer's suggestions.
    You will probably be ok with Vitamin C powder as long as it specifies ascorbic acid. Dehydroascorbic acid is also Vitamin C to the body but is not the form we want. The pills that say they contain ascorbic acid have binder, probably starch. Whatever it is does not seem to interfere with the chemical effects but might leave precipitates. Even if they are not harmful, they are not desirable. Anthing like that gives me the feeling that it might be a sign that something is in my developer that I don't want to be there. Call it paranoia or just being cautious.

    Technical grade ascorbic acid or its isomer erythorbic acid are equivalent for photo use.
    Gadget Gainer

  2. #12

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    Filtering your dev mixture before using would be a good idea!

  3. #13
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    I found pure crystaline ascorbic acid at a health food store. I think it was ~$10 for a half pound jar. Leaves no precipitate.

  4. #14
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    Well, I found pure crystalline ascorbic acid at a health food store too but from there on, it's been a disaster. I've ruined a good quantity of TEA trying to dissolve the darned stuff. When I worked from a kit from Artcraft for my 510 Pyro it went smooth as can be. Now all I have is two quantities of TEA with ascorbic gunk at the bottom and no idea what to do now. Any suggestions?
    Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In velit arcu, consequat at, interdum sit amet, consequat in, quam.

  5. #15
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    Quote Originally Posted by jstraw View Post
    I just got my Artcraft order and realized I forgot to order my ascorbic acid. What sort of vendors might I check with locally for it? Can I just grind up vitamin c tablets or are they adulterated with things I'd want to avoid?
    If you have a Trader Joe's store near you, they sell Ascorbic Acid for $9.99 a pound. It can be found in the vitamin section.

    Mike
    When the chips are down,

    The buffalo is empty!!!



  6. #16
    gainer's Avatar
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    Quote Originally Posted by jstraw View Post
    Well, I found pure crystalline ascorbic acid at a health food store too but from there on, it's been a disaster. I've ruined a good quantity of TEA trying to dissolve the darned stuff. When I worked from a kit from Artcraft for my 510 Pyro it went smooth as can be. Now all I have is two quantities of TEA with ascorbic gunk at the bottom and no idea what to do now. Any suggestions?
    Taste the crysrals. It might be sodium ascorbate, which is near neutral pH. If it's the acid, your tongue will know. If it's the ascorbate, forget trying to dissolve it in either glycol or TEA.

    What brand name is on the Vitamin C? At some places you can get the acid or the sodium salt or the calcium salt.
    Gadget Gainer

  7. #17
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    It's ascorbic acid. I don't know what the issue is but that's not it.
    Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In velit arcu, consequat at, interdum sit amet, consequat in, quam.

  8. #18
    gainer's Avatar
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    Let's go to the beginning. What was your recipe?
    Where did you get the TEA, and what grade is it?
    Did you warm the TEA?
    Do you think most, some or hardly any of the ascorbic acid dissolved?
    Did you try making a working solution from the clear part of what you got and running a snip test to see if it developed?

    Contrast vs C/P ratio at constant development time changes very little for C/P > 40. Thus, if you can dissolve 1 gram of phenidone and 40 grams or more of ascorbic acid in TEA, you should be able to find a dilution of that solution that will develop your film in a reasonable time.

    Another solution is PC dissolved in propylene glycol, used as A, and TEA or almost any other alkali as B in a 2-part developer.
    Gadget Gainer

  9. #19
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    Quote Originally Posted by gainer View Post
    Let's go to the beginning. What was your recipe?
    The recipe published in the articles section here.

    Quote Originally Posted by gainer View Post
    Where did you get the TEA, and what grade is it?
    It's whatever Artcraft sells.


    Quote Originally Posted by gainer View Post
    Did you warm the TEA?
    Yes

    Quote Originally Posted by gainer View Post
    Do you think most, some or hardly any of the ascorbic acid dissolved?
    Some.

    Quote Originally Posted by gainer View Post
    Did you try making a working solution from the clear part of what you got and running a snip test to see if it developed?
    When the ascorbic acid refused to go into solution, I decided not to waste any pyrogallol or phenidone.

    Quote Originally Posted by gainer View Post
    Contrast vs C/P ratio at constant development time changes very little for C/P > 40. Thus, if you can dissolve 1 gram of phenidone and 40 grams or more of ascorbic acid in TEA, you should be able to find a dilution of that solution that will develop your film in a reasonable time.
    I'm unfamiliar with the term "C/P." I already have working times for 510-Pyro...if I could just make some.

    Quote Originally Posted by gainer View Post
    Another solution is PC dissolved in propylene glycol, used as A, and TEA or almost any other alkali as B in a 2-part developer.
    Using an alternative staining developer (one that I can buy...hello Photographer's Formulary!) and abandoning 510-Pyro is probably just around the corner.
    Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In velit arcu, consequat at, interdum sit amet, consequat in, quam.

  10. #20
    Lee L's Avatar
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    Quote Originally Posted by jstraw View Post
    I'm unfamiliar with the term "C/P."
    Ratio of vitamin C (ascorbic acid form in this case) to Phenidone.

    Lee

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