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  1. #1

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    Speed increasing ascorbate/carbonate developer

    This is based on my previous finding that a developer with high ascorbate and carbonate lasts a long time exposed to air in a half full bottle.My theory is that all the air only oxidizes a small proportion of the ascorbate and the high carbonate means the acid so produced does not cause a significant pH drop.
    I call the developer "3W" after the 3 witches in Shakespeare's Macbeth.

    3W developer
    Water.......................................850ml
    Dimezone-S..(stir till dissolved)........1g
    Sodium Sulfite..............................20g
    Ascorbic Acid (Vitamin C)...............20g
    Sodium Carbonate anhydrous.........40g
    filter through cotton wool.
    Water to........................................1L
    pH~9.8
    Develop about 10% less than for Xtol 1+0

    I have not measured the speed increase compared to D-76 accurately but the attached pics on APX 100 exposed at EI=200 (average metering) show there is an increase.
    Phenidone may be used in place of Dimezone-S but the developer may then be less resistant to hydrolysis if it is left unused for a long time.
    Previously Gainer formulated various ascorbate developers but unlike them the present brew contains sulfite to uncover latent image specks and provide an increase in EI.
    Thanks for comment.
    Attached Thumbnails Attached Thumbnails 3W 1.jpg   3W 2.jpg   3W 3.jpg  

  2. #2

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    My first thoughts are I'd be concerned about graininess and fog given the various aspects of this formulation. The development time is interesting, as I would have expected a formula with that much Dimezone and Carbonate at that high a pH to work much faster than XTOL. It seems closer to a print developer in formulation but without a restrainer.

    Interesting work. How did you arrive at the 20:1 ascorbate/Dimezone ratio?

  3. #3
    Rudeofus's Avatar
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    Quote Originally Posted by Michael R 1974 View Post
    The development time is interesting, as I would have expected a formula with that much Dimezone and Carbonate at that high a pH to work much faster than XTOL. It seems closer to a print developer in formulation but without a restrainer.
    +1 to that. I'm very surprised to see such a long dev time for that much Phenidone plus strong secondary dev plus pH close to 10 ...

    And I'm also surprised to see that 40 g/l Sodium Carbonate plus 20 g/l Ascorbic Acid gave you pH 9.8 ....
    Trying to be the best of whatever I am, even if what I am is no good.

  4. #4

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    Would you have expected the pH to be higher or lower than 9.8?

    Regarding the development time, I guess what what don't know is the contrast obtained in the test images.

  5. #5
    David Allen's Avatar
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    Very strange tonality - kind of reminds me of reproductions in magazine from the late 40s and 50s.

    Not my cup of tea!

    Bests,

    David
    www.dsallen.de

  6. #6
    Rudeofus's Avatar
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    Initially I would have thought pH should be lower. But given Ascorbic Acids high molecular weight I may be wrong.

    What still amazes me is the dev time Alan claims to need. E6 FD with 1 g/l Phenidone, 20 g/l HQMS and pH 9.5 develops Tri-X in less than a minute. When I developed Tri-X for 5 minutes at 30°C (which should equal 10-15 minutes at RT) with E6 FD diluted 1+1, I got a four stop push judging from the characteristic curve. And yes, such intense overdevelopment will raise shadow detail.
    Trying to be the best of whatever I am, even if what I am is no good.

  7. #7

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    Interesting.
    I played with an Metol/Ascorbic Acid developer (ratio Metol 1:4 Ascorbic Acid) a few months ago, using Sodium Carbonate as the alkali, (although the original formula called for metaborate) and got some rather good results, excellent tone and sharpness, and nowhere near as much grain as I see in the attachments above. The formula was I believe a Kodak "lab developer" used for testing emulsions. it was pretty "hot" though, development times were stupidly short. I never pursued trying to tame it as I'm no chemist, just a fiddler.

  8. #8

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    I forgot to mention that the developer is hoped to be re-useable but rather than wait it is convenient to write it up in bite-size chunks.I hope to report future results on the same glass bottle of W3.
    The ratio ascorbate:dimezone-s is within limits suggested by Gainer, dimezone-s is a bit heavier than phenidone per mole:
    http://unblinkingeye.com/Articles/Sy...synergism.html

    I too expected a shorter development time.I have no densitometer but the contrast looks slightly less than what I get with Xtol and was a surprise and hard to explain.
    Perhaps dimezone-s is adsorbed on silver bromide crystals and once it covers the surface adding more does not make much difference. This aspect of chemistry is not my thing.
    Measuring the pH again gave 9.8, meter calibrated 6.9, 9.2 and checked afterwards with 5g/L Na2CO3 measured pH=11.1. I'm not entirely happy with this cheap meter.

    The pics were taken with an orange filter and I had to increase the contrast after scanning to get blacks. I doubt there is anything particularly unusual about the tonality of W3.

    Yes it is grainy and unless this is wanted Xtol pushing would probably be better. There are occasions where it is convenient to shoot 100 box speed film at EI=200.

  9. #9
    BradS's Avatar
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    The results seem very good to me. I like the tonality....but, I think the effect due to the orange filter is the much larger than any effect due to the developer.

    I am very curious about the fog levels. Based upon my experiments with similar concoctions (yes, Gainer influenced many of us), I would expect considerable fog.
    What do you observe with respect to fog levels compared to D76?

  10. #10

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    Hi Brad,
    Hope you can get an idea of the fog levels with D-76d EI=100 and W3 EI=200 from the attached pics on a lightbox.
    Attached Thumbnails Attached Thumbnails fog.jpg  

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