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  1. #11
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    Quote Originally Posted by David A. Goldfarb
    Regarding the cost of Michael Smith's amidol formula--what I've taken to doing when I don't have a lot of Azo prints to make is that I run the Azo prints first, then add the appropriate amount of KBr and benzotriazole to the amidol to run enlargements in it, mostly on Cachet/Maco Expo RF, which looks really nice in amidol.

    Thanks for the tip David! Now I can use that Amidol thats been sitting in my closet for the past 6 mos. I have plenty of enlargements that I can do, but only a few contacts that are worth running through Amidol.
    RL Foley

  2. #12

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    I have followed the results and Tom and of Ron as well. Ron's results are interesting since I have not used citric acid as a preservative before.

    My results are not consistant with what Tom has indicated. But then I do not prepare stock solutions preferring instead to mix the developer from individual chemicals immediately prior to use. It takes a little longer but the results are consistant in my experience.

    I have not experience the dmax going red in my use of the developer. I can not explain the difference other then the difference that I previously noted. (stock solution preparation).

    Sandy King found the developer depleting very rapidly and that was due to the formula as published on www.unblinkingeye.com being inaccurate. (No sulfite noted in that published formula.)

    I have found that increasing catechol proportionally to pyrogallol decreases contrast and effective paper speed. By increasing the pyrogallol proportionally to catechol the contrast and paper speed do increase in my tests. I have varied the proportion from 10-5 (catechol to pyrogallol) to 0-15 (catechol to pyrogallol). The remainder of the ingredients remained the same insofar as the ingredients themselves and the amounts used.

    Lee Carmichael has used the developer from individual ingredients (no stock solutions) that I provided to him when he was at my home several months ago. He reports that the developer performed as I had indicated.

  3. #13
    lee
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    Lee Carmichael has used the developer from individual ingredients (no stock solutions) that I provided to him when he was at my home several months ago. He reports that the developer performed as I had indicated.

    That is how it worked for me.

    lee\c

  4. #14

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    Quote Originally Posted by Donald Miller
    I have not experience the dmax going red in my use of the developer. I can not explain the difference other then the difference that I previously noted. (stock solution preparation).
    Don, that is because you put Potassium Bromide (a restrainer) into your working developer and I did not.

    As I previously tried to explain (and not very well), the red tones, high contrast and high activity level were the result of my deliberately mixing and using the developer without the Potassium Bromide - I wanted to see what the color and activity level would be without the bromide. When I added Potassium Bromide to that same working developer solution (twice as much bromide as I should have added), the red color disappeared,the developer activity slowed, and the contrast dropped. The resulting Azo prints were quite nice.
    Tom Hoskinson
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  5. #15

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    Tom,
    Thanks for clarifying this for me. I didn't understand that the prints with KBR added were acceptable. I wonder if increasing the pyrogallol proportion would bring the contrast to acceptable levels for you. Please let me know if this works for you if you decide to try it.

    Quote Originally Posted by Tom Hoskinson
    Don, that is because you put Potassium Bromide (a restrainer) into your working developer and I did not.

    As I previously tried to explain (and not very well), the red tones, high contrast and high activity level were the result of my deliberately mixing and using the developer without the Potassium Bromide - I wanted to see what the color and activity level would be without the bromide. When I added Potassium Bromide to that same working developer solution (twice as much bromide as I should have added), the red color disappeared,the developer activity slowed, and the contrast dropped. The resulting Azo prints were quite nice.

  6. #16

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    Don, the first thing I will try is putting in your recommended amount of potassium bromide (3.5 gm Potassium Bromide for 2 liters of working developer).

    IMO, the potential ability to raise and lower contrast and change the image tone by adjusting the amount of potassium bromide in the working developer is a good thing!

    And as you have mentioned, adjusting the amount of Pyrogallol and/or Pyrocatechol, thus changing the Pyrogallol/Pyrocatechol ratio, are also potential "knobs" for adjusting contrast and tone.

    Dilution is another potential knob.

    Increasing the amount of water in the working solution should decrease the contrast and change the image tone (colder, I would think).

    Decreasing the amount of water in the working solution should raise the contrast and change the image tone (warmer, I would think).
    Tom Hoskinson
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