Patton's E-76

Discussion in 'B&W: Film, Paper, Chemistry' started by BradS, Jan 29, 2008.

  1. BradS

    BradS Subscriber

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    This past weekend, I mixed up a liter of Patton's E-76. I'm a dedicated D-23 and HC-110 user but, deviate from my habitual use of these two from time-to-time.

    I've not tried E-76. It is advertised as an eco-friendly, metol and HQ free D-76 alternative.

    How does it compare to D-76 in actual use?

    Can D-76 times be used straight away?

    Is there likely to be any improvement in shadow density?

    How does it keep?
     
  2. jim appleyard

    jim appleyard Member

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    I tried one batch of this a while ago, so take this advice FWIW; I thought it was quite good and IIRC, I used D-76 times for 35mm. However, I found that I needed to add 20% to the time for 120 rolls.

    I did not notice any improvement of D-76 in shadow detail. It was no worse, either.

    As always, test rolls are advised!
     
    Last edited by a moderator: Jan 29, 2008
  3. Snapshot

    Snapshot Member

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    That's odd. I found the E-76 formula to be more active and used stock D-76 times for 1+1 dilutions. Regardless, you'll find that this developer is as good as D-76.
     
  4. jim appleyard

    jim appleyard Member

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    I really should amend my post. Snapshot's post reminded me that I used "Vitamin C" from the health-food store for my E-76. There are several kinds of Vitamin C; some are good as devs, some are not. This may explain my dev times. The "Vitamin C" I used did leave a precipitate when mixed.

    Negs came out fine, tho.

    I believe Pat Gainer's a ascorbic acid/sodium ascorbate fan. Perhaps he will join this thread and help out.
     
  5. Jordan

    Jordan Member

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    I used E-76 a few years ago. I used a good grade of crystalline ascorbic acid and found the developer to be far more active than D-76 (results similar to Snapshot's).
     
  6. nworth

    nworth Subscriber

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    I saw the original E-76 note (it wasn't quite an article) several years ago and tried it (I think with Plux-X Pan). The note suggested using the same times as for D-76. My results were somewhat harsher but still very slightly thiner than my comparison shots processed in D-76. The test was far from definitive, and E-76 seems to be generally similar to D-76.
     
  7. gainer

    gainer Subscriber

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    I have seen calcium ascorbate, dehydroascorbic acid and unidentified compounds sold as vitamin C. The human body can certainly use calcium ascorbate as C, but it causes precipitation in developers with carbonate. The dehydroascorbic acid is what results as ascorbic acid is oxidized in developers. The body converts ascorbic acid to this compound, which will pass the into the brain, there to be converted back to the vitamin by reactions our developers don't have (and we probably don't want them to have). Stay away from anything identified as "Ester C". It is easy to convert ascorbic acid to sodium ascorbate. 10 grams of ascorbic acid + 4.8 grams of sodium bicarbonate in a small amount of water make 11.25 grams of sodium ascorbate + a bunch of CO2 which fizzes away.

    Whether you add sulfite or not, a developer containing Metol, sodium ascorbate and borax will have considerable activity. It is a good way to learn how much sulfite you really want for your purposes. If you didn't use any sulfite in D-76, you would find the synergism usually attributed to the MQ combination to be missing. Ascorbate takes the place of sulfite by replenishing the Metol instead of keeping the oxidized Metol from retarding the reaction, but seems not to have much ability to chew away the grain edges. That in itself gives no sure prediction of differences in graininess, because the structure of the grain clumps is different with and without sulfite in an ascorbate developer. A developer might first build up grain clumps and then dissolve their edges, or it might gradually build up groups of very tiny particles to reach a given density.


    ascorbic and erythorbic acids are l-ascorcic acid and d-ascorbic acid, mirror images that our bodies can tell apart but our developers cannot.
     
  8. BradS

    BradS Subscriber

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    hmmm, I used ascorbic acid crystals from the health food store. Nothing fell out of solution when I added the Vit-C but, I did get some blobs of stuff in the filter paper. Oddly enough, the blobs looks faintly like small bits of pulp from an orange or other citrus fruit (???).