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  1. #11
    dpurdy's Avatar
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    Quote Originally Posted by Lee Shively View Post
    I buy the mentioned sulfites from this place:

    http://www.chemistrystore.com/index.html

    There may be a cheaper source but the prices here are pretty good compared to photo-designated chemical sources.
    That place is great. thanks. Check the price of sodium carbonate as well.
    I will use them next time.
    Dennis

  2. #12

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    My reciepe is:
    110g Sodiumsulfit
    28 Sodiummetabisulfit
    5,5g EDTA Tetrasodiumsalt
    5,5 Sodiumcitrate

    Even with that reciepe in which the EDTA and the citrate serve as complexing agents for keeping the calcium und magnesium ions from tap water in solution, with my iron polluted tap water a white percipate may occur, that could rest as a grayish scum on the prints. So good tap water is fine but in my case I have to use reverse osmosis water.

  3. #13

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    Quote Originally Posted by BBMOR View Post
    ...,seewater is the cheapest if you live close enough
    Soon enough many will be living closer than they care. Dan

  4. #14

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    Quote Originally Posted by BBMOR View Post
    hey

    the home brewed washaid with bisulfit or Na carbonate or even salt, normal NaCl kan be used ,never use destilled or softed water for m ,the more salt in the water the better it can be used as a washaid ,seewater is the cheapest if you live close enough
    using sea water reduces washing times as well.
    but then you have to deal with all that plankton .

  5. #15

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    Quote Originally Posted by fschifano View Post
    No wash aid at working strength has a long shelf life,
    so just chuck it at the end of the session.
    Ian has mentioned Agfa's recommended sodium carbonate.
    On a pound for pound basis, IIRC, about 1/4 more equals
    sodium sulfite in capacity. S. carbonate though does not
    need to be chucked. So compare with S. sulfite which
    starts going bad as soon as the lid is off.

    I think sulfite is used in a fingers crossed manor. It oxidizes
    into the sulfate. With a most minute amount of certain
    elements in the water or the sulfite itself it will
    experience catalytic accelerated oxidation.

    Perhaps that is why Agfa never followed the pack and
    for many years recommended sodium carbonate. There is
    no ?"how shot is my hca?" from being exposed and stirred
    and in and out of the bottle. The only issue with carbonate
    is capacity. Agfa's 2% solution strength I'd think would
    yield about the same capacity as a sulfite based HCA.
    Perhaps Ian can add a few more details of the Agfa
    method. Considering the importance of an hca in
    reducing time and water needs the use of any
    HCA should be better defined. Dan

  6. #16
    Ian Grant's Avatar
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    This is from the Agfa Data sheet for Record Rapid:

    A soda bath (1 % sodium carbonate solution) can be included for fiber-base paper, between fixer and final wash. This ensures that the fixer is washed off the paper surface faster and more thoroughly. This not only cuts down the final washing time by about 30 %, and in particular it increases the prints' durability. If a hardener-fixer is used, the soda intermediate bath is not recommended.

    L F Mason in his book Photographic Processing Chemistry mentions the use of Sodium Carbonate or Sodium Sulphite as a wash aid. Mason was head of research at Ilford.

    Ian

  7. #17

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    [QUOTES=Ian Grant;541001]
    "This is from the Agfa Data sheet for Record Rapid:"

    "A soda bath (1 % sodium carbonate solution) can be included
    for fiber-base paper, between fixer and final wash. This ensures
    that the fixer is washed off the paper surface faster and more
    thoroughly. This not only cuts down the final washing time by
    about 30 %, and in particular it increases the prints' durability.
    If a hardener-fixer is used, the soda intermediate bath is
    not recommended."

    That last sentence likely explains why sulfite is the usual
    base of HCAs. It works well and has a lower ph, safer for
    fixer-hardened emulsions. With today's pre-hardened
    emulsions sulfite's advantage is likely lost. I doubt
    Agfa would otherwise suggest carbonate. For
    myself a HCA which does age is advantages.

    The problem with carbonate is that it's use is not well
    spelled out; times, capacity, and ?. Dan

    "L F Mason in his book Photographic Processing Chemistry
    mentions the use of Sodium Carbonate or Sodium Sulphite
    as a wash aid. Mason was head of research at Ilford." Ian

  8. #18
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    right wrong or indifferent, I have been using a two bath wash. My darkroom has water storage and disposal but not an endless supply for either so I have been putting my prints (fiber or RC) in a 5gal bucket full of water with a few tablespoons of sulfite for about 10 minutes and then in a large sink filled with about 25 gal of fresh water for another 30 minutes or so. I figure the leaching and thiosulfate concentrations will be very very small after this and so I am using this for now.
    My photos are always without all that distracting color ...

  9. #19

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    [QUOTES=dancqu;541904]

    "That last sentence likely explains why sulfite is the usual
    base of HCAs. It works well and has a lower ph, safer for
    fixer-hardened emulsions. With today's pre-hardened
    emulsions sulfite's advantage is likely lost. I doubt
    Agfa would otherwise suggest carbonate. For
    myself a HCA which does age is advantages."

    That last sentence should read, ...does NOT age... .
    Carbonate that is. It does not oxidize.

    "The problem with carbonate is that it's use is not well
    spelled out; times, capacity, and ?." Dan

  10. #20
    KWhitmore's Avatar
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    LOL

    Quote Originally Posted by jnanian View Post
    using sea water reduces washing times as well.
    but then you have to deal with all that plankton .
    Um, what kind of food do they serve at the Chum Bucket other than Krabby patties? That's soooo funny.

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