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  1. #11
    RPC
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    Quote Originally Posted by newcan1 View Post
    Would the contrast have been increased by reducing the sulfite from 1g/L to 0.2g/L?
    Yes, that is why I reduced it. The contrast was too low with 1 g. You might try no sulfite, but shelf life would be even less.

  2. #12
    RPC
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    Quote Originally Posted by Photo Engineer View Post
    The pH is critical and should be about 10.5. The additional secret is the use of Lithium salts and and a Sulfonic acid. These changes were needed to offset the removal of Benzyl Alcohol and improve development rate.

    So, IMHO, none of the internet formulas are correct so far. If I can find one, I'll post it here someday.

    PE
    Qualitywise, this developer is very good and works superbly with Fuji CAII paper and Endura paper. Its only downside as I mentioned earlier is tar (I get a stain in my trays), and short shelf life. I have seen the formula by Steven Keirstead, which no doubt solves these problems, but in my opinion is too complex and probably is not worth the trouble for the typical home user, considering the image quality of this developer.

  3. #13

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    I use drums and they are washed between each use so I dont think tar is a problem for me. I agree, the developer as tweaked seems very good, and the other formula does involve some expensive/hard to source chemicals.

    I am about to use up my liter of "tweaked" developer, and will make up another batch with the original amount of carbonate and maybe 6g CD3, and see what happens. I want to end up with one formula optimized for general use, and one for printing ECN-2 negatives.

    Reflectin on PE's comment that you posted above -- I wonder what would happen if one were to take out triethanolamine and replace it with benzyl alcohol?

  4. #14
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    The RA4 developer uses Hydroxyl Amine Oxalate to prevent stain and tar and to help reserve the developer. You can substitute Hydroxyl Amine Sulfate with the correct adjustment in amount. The recommended brightener is chosen to prevent yellowing with keeping. Some brighteners yellow heavily with age.

    PE

  5. #15
    RPC
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    Quote Originally Posted by Photo Engineer View Post
    The RA4 developer uses Hydroxyl Amine Oxalate to prevent stain and tar and to help reserve the developer. You can substitute Hydroxyl Amine Sulfate with the correct adjustment in amount.
    PE
    Thanks. I will try it sometime.

  6. #16
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    Quote Originally Posted by newcan1 View Post
    Reflectin on PE's comment that you posted above -- I wonder what would happen if one were to take out triethanolamine and replace it with benzyl alcohol?
    Triethanolamine is a strong alkali while Benzylalcohol isn't, so you will have to adjust pH if you really want to avoid Triethanolamine.
    Trying to be the best of whatever I am, even if what I am is no good.

  7. #17

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    PE indicates that HAS can be used as a preservative.....is that all it does? The formula we have been discussing works pretty well, and now I'm wondering what would happen in the context of C41 developer if HAS were omitted? Because it's one of the more expensive ingredients.

  8. #18
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    Quote Originally Posted by newcan1 View Post
    PE indicates that HAS can be used as a preservative.....is that all it does? The formula we have been discussing works pretty well, and now I'm wondering what would happen in the context of C41 developer if HAS were omitted? Because it's one of the more expensive ingredients.
    AFAIK it is used as a preservative. It is also quite acidic, so be prepared for strong pH adjustments after adding it to your recipe. Unlike Sulfite, it doesn't react with oxidized developer which means it doesn't prevent the dye coupler reaction we need for color processes.
    Trying to be the best of whatever I am, even if what I am is no good.

  9. #19
    RPC
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    I have tried C-41 developer without HAS and with pH adjustment seemed to work well, but one would expect a shorter shelf life.

  10. #20

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    What did you use for the pH adjustment? More carbonate?

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