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  1. #11
    Trask's Avatar
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    Ian, what's the replenisher formula? I'm trying to gain an understanding of how one could take any particular formula, and derive a replenisher. I believe that bromides will build in a replenished developer, so presumably one would have less of one component in the replenisher than in the straight developer.

  2. #12
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    Adox Borax MQ Replenisher

    Metol 3g
    Sodium Sulphite 80g
    Hydroquinone 5g
    Borax 18g
    Water to 1 litre

    Replenish at 15-20ml per 35mm/120 film, discard any excess developer.


    Ilford chemists wrote a series of articles in the 1950's discussing formulating a PQ version of ID-11/D76 there was also a parallel artice on determining exhaustion rates and then replenishment.

    The issue with an MQ developer is Bromide build up which is a limiting factor, bromide surpresses Metol so MQ developers need to be developed on a bleed system which means discarding developer before adding replenisher, this reduces the bromide build up/

    Phenidone can tolertate much higher levels of Bromide so you can use a topping up system which is far more economic. One consequence of Ilford#s research was the release of Autophen a commercial PQ fine grain developer, the formula was published in a BJP article, it's in Jacobson, Developing as well called Axford-Kendall Fine Grain Developer with two different replenishers one for Topping up, the other for Bleed systems. Some books mistakenly claim the Autophen (PQ variant of ID-11/D76) formula is the same as Microphen, which is in fact ID-68.

    I did list these formula in an article here on APUG- The Ilford PQ variants of ID-11 (D76) That may give you some ideas of the differences in replenishers.

    Ian

  3. #13
    JPD
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    The similar Agfa 17 is my standard developer. I use it 1+1.

    Warm Water 750 ml
    Metol 1.5 g
    Sodium Sulfite (Anhydrous) 80 g
    Hydroquinone 3 g
    Borax 3 g
    Potassium Bromide 0.5 g
    Cold Water to make 1 ltr
    J. Patric Dahlén

  4. #14
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    Agfa 44

    Just to correct you this is Agfa 44 later called Orwo 44

    It's also published as Agfa Ansco /GAF 17. Agfa is a German company and when they owned Ansco the US Agfa Ansco used different numbers to Germany, they also made miscalcutions in converting Anhydrous weights to monohyrate in some fomulae.

    Ian


    Quote Originally Posted by JPD View Post
    The similar Agfa 17 is my standard developer. I use it 1+1.

    Warm Water 750 ml
    Metol 1.5 g
    Sodium Sulfite (Anhydrous) 80 g
    Hydroquinone 3 g
    Borax 3 g
    Potassium Bromide 0.5 g
    Cold Water to make 1 ltr

  5. #15

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    Quote Originally Posted by Alan Johnson View Post
    This is what Crawley said about Adox MQ Borax in BJP Dec 16 1960,the earliest reference to it I have found:
    "The concentration of sodium sulphite is 20 grammes lower than in D.76,which reduces the amount of physical development and improves sharpness.The sheen referred to earlier in D.76 appears to be caused by the nature of borax alkalinity (in a sensitive carbonate chemical developer the introduction of borax in a concentration of 0.1 grammes per litre will produce a slight sheen).The addition of potassium bromide to a borax developer will remove this sheen virtually entirely,for it appears to prevent discontinuities usually caused by borax alkalinity.The buffering of Borax with added boric acid does not seem to improve definition,although the borax sheen is reduced and sharpness improved.Adox MQ Borax has times slightly longer than D.76,contrast rising more slowly."
    I have never understood what Crawley meant about the so called "borate sheen" or seen any scientific evidence to back it up. Borax actually releases some boric acid when gets dissolved, so how can adding boric acid help except for increasing the buffering capacity?

  6. #16
    JPD
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    Quote Originally Posted by Ian Grant View Post
    Just to correct you this is Agfa 44 later called Orwo 44

    It's also published as Agfa Ansco /GAF 17. Agfa is a German company and when they owned Ansco the US Agfa Ansco used different numbers to Germany
    It's both raining and snowing, but I had to walk to my darkroom to check it up in the book "Agfa Rezepte" (Agfa Wolfen, 1960) i keep there. Yes, it's Agfa 44. Thanks for correcting me.

    The real Agfa 17 isn't published in this book.
    J. Patric Dahlén

  7. #17

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    Quote Originally Posted by Keith Tapscott. View Post
    Borax actually releases some boric acid when gets dissolved, so how can adding boric acid help except for increasing the buffering capacity?
    Crawley,BJP Dec 30 1960:
    "The significance of the borates is really not confined to their self-buffering action,they have in addition a restraining action on development.It is well known that borax readily forms complexes with organic substances,and it would seem likely that it does so with the developing agency,with a density depressing effect.............in an energetic carbonate developer with a fairly low concentration of developing agency to make it sensitive,a very small addition of borax-0.1 gm/litre-will give depression which could not originate from any effect on alkalinity.Sodium metaborates also show this effect but to a very much lower extent,and will not per se provoke a strong dichroic sheen.......... ."

    I think he is saying the sheen he saw is related to the complexing of borax with the developing agents.

  8. #18

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    It's long been known that borates in a hydroquinone containing developer lower the amount of developer fog. It is believed that the borate ion combines with certain oxidation products and prevents them from acting as developing agents. The effect is not seen with other developing agents such as metol.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  9. #19
    JPD
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    Quote Originally Posted by Gerald C Koch View Post
    It's long been known that borates in a hydroquinone containing developer lower the amount of developer fog. It is believed that the borate ion combines with certain oxidation products and prevents them from acting as developing agents. The effect is not seen with other developing agents such as metol.
    If that's the case, is the Potassium bromide still needed?
    J. Patric Dahlén

  10. #20

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    Quote Originally Posted by JPD View Post
    If that's the case, is the Potassium bromide still needed?
    Adox MQ is similar to D-76 which does not use KBr. Try mixing the Adox formula without the bromide and see if you like the results.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

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