Adox MQ Borax Formula.

Discussion in 'Darkroom Developing and Printing' started by Keith Tapscott, Aug 21, 2005.

  1. I have read two different formulas for the Adox MQ Borax fine grain
    developer, one gives one gramme per litre and the other gives two grammes
    per litre, which one is the official Adox formula?
    Also, was there a replenisher formula for this?
     
    Keith Tapscott, Aug 21, 2005
    #1
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  2. Keith Tapscott

    UC Guest

    UC, Aug 21, 2005
    #2
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  3. That sounds like the old Agfa 17 formula.

    Agfa/Ansco 17

    Water (at 125F or 52C) 750.0 ml
    Metol 1.5 grams
    Sodium sulfite, dessicated 80.0 grams
    Hydroquinone 3.0 grams
    Borax, granular 3.0 grams
    Potassium bromide 0.5 gram
    Water to make 1.0 liter

    80 grams of sulfite per liter is probably closer to the
    optimum than the 100 grams in D-76, not a big deal. In their
    1929 paper on D-76 Carlton and Crabtree (of Kodak Labs)
    tried about 30 variations of D-76 including one with a small
    amount of bromide in it. They used 0.75 grams/liter. The
    results were a slight increase in film speed due to
    reduction of the slight fog that _unused_ D-76 produces.
    When the developer is used some bromide comes out of the
    film so used developer or replenished developer has bromide
    in it. Carton and Crabtree's paper announced the buffered
    version of D-76. The buffering was to eliminate a slow
    increase in activity of the developer over time. Carlton and
    Crabtree did not know what caused the rise other than it was
    associated with an increase in pH. It turns out that this
    was due to a slow reaction between the Hydroquinone and
    Sulfite, which produces some Sodium hydroxide. It also
    produces some reaction products of Hydroquinone which are
    active developers, but they are not active at the relativly
    low pH of D-76 so are not part of this problem. Current
    packaged D-76 is the buffered variety. It would be possible
    to buffer the Agfa formula by adding Sodium bisulfite (or
    metabisulfite) in the correct amount.

    The following is the replenisher formula for Agfa 17

    Agfa 17 Replenisher
    Water (at 125F or 52C) 750.0 ml
    Metol 2.2 grams
    Sodium sulfite, dessicated 80.0 grams
    Hydroquinone 4.5 grams
    Borax, granular 18.0 grams
    Water to make 1.0 liter

    Add 15ml to 22 ml of replenisher for each 80 square inches
    of film developed (equivalent to one roll of 120 film or one
    36 exposure roll of 35mm film).
     
    Richard Knoppow, Aug 22, 2005
    #3
  4. Keith Tapscott

    UC Guest

    Similar to the Agfa formula, but distinct.

     
    UC, Aug 22, 2005
    #4
  5. * Metol :- 2 grammes
    * Sodium Sulphite, anhydrous :- 80 grammes
    * Hydroquinone :- 4 grammes
    * Borax :- 4 grammes
    * Potassium Bromide :- 0.5 grammes
    * Water to :- 1000ml.

    This is a variation of D-76 that gives slightly better sharpness but
    development times must be increased by 10 - 20 %.

    http://www.cjballphotography.org.uk/formulae.html#formulae

    Glenn Booth
     
    ieverettmemun, Aug 22, 2005
    #5
  6. Keith Tapscott

    dan.c.quinn Guest

    That formula agrees with the one in P. Dignan's Classic B&W Formulas.
     
    dan.c.quinn, Aug 22, 2005
    #6
  7. Nearly every film manufacturer published some version of
    D-76, usually with some small variation to make his own.
    From research done recently by Ryuji Suzuki it appears that
    the Agfa formula is slightly superior to the original Kodak
    formula but it would be difficult to see it in practice. I
    have taken to adding 0.5 gram /liter of Potassium bromide to
    D-76. I _think_ this is giving me slightly cleaner
    negatives. I use D-76 diluted 1:1 as a one shot. As
    mentioned in my other post bromide accumulates in reused or
    replenished developers so, if you work that way, adding
    bromide is useful only as a "developer starter" to get the
    system to equilibrium a bit faster.
    There are an enormous number of developers which can be
    seen as D-76 derivitives. Among them similar developers
    using Metaborate in place of Borax, or Phenidone in place of
    Metol (Microphen).
    Even Xtol can be seen as a D-76 type developer where
    Metaborate replaces the Borax buffer, and a Phenidone
    (actually Kodak Dimezone-S) and Ascorbic acid replace the
    Metol-Hydroquinone system.
    D-76 has been around since 1927 when it was first
    published as a fine grain developer for duplicating motion
    picture negative films. In 1929 an extensive paper was
    written by Crabtree and Carlton of Kodak Labs describing a
    large number of variations and introducing the buffered
    version. It has remained the standard of comparison for B&W
    negative developers ever since. D-76 is attributed to John
    G. Capstaff, of Kodak Labs, who also worked out the methods
    for reversal processing that made 16mm home movies
    practicable.
     
    Richard Knoppow, Aug 23, 2005
    #7
  8. I wonder if anyone has tried this and can confirm either
    statement. The developer is more active than D-76, not the
    double amount of Borax and there is nothing in it to suggest
    is produces more edge (acutance) effects.
     
    Richard Knoppow, Aug 23, 2005
    #8
  9. Keith Tapscott

    UC Guest

    The lower amount of sulphite is supposed to reduce the loss of
    definition due to sulphite solvency. That's what Crawley claims. The
    presence of a small amount of bromide may also contribute to better
    sharpness than straight D-76, if I recall correctly.
     
    UC, Aug 23, 2005
    #9
  10. Interesting. The action of sulfite is to dissolve a small
    amount of the surface of each silver grain. Where the action
    is limited, as in D-76, D-23, etc, the effect is raise film
    speed slightly because it exposes more development centers
    to the developer. High sulfite also affects the shape of the
    developing silver crystals. All this has little effect on
    resolution.
    We should be careful to distinguish resolution from
    sharpness, they are not the same. Resolution is a measure of
    the ability of the film to record fine details. The
    resolution limit is determined for some fixed contrast
    between the dark and light adjacent lines. Most film
    resolution numbers, as given by manufactuers, is for high
    contrast targets, 1:1000, Kodak also gives values for low
    contrast (typically 1:30 brightness ratio) targets. The
    limiting factor for resolution is usually the amount of
    scattering to light in the emulsion, an effect known as
    irradiation. Modern films, which have relatively thin
    emulsions, have less scattering, hence higher resolution,
    than the films of the past.
    Sharpness is a perceived quality. To a large extent it is
    independant of resolution. The eye judges sharpness largely
    by the contrast at the demarcation of light and dark areas.
    If the transition is sharply defined the eye intreprets it
    as meaning the image is sharp. It is possible to have high
    resolution images which do not appear sharp because the edge
    contrast is low and vice-versa. Kodak Labs did a lot of
    research on perceived sharpness and came up with the term
    Acutance to indicate the effect. Acutance can be improved by
    a developer which exagerates the contrast at edges. This is
    known as the adjacency effect, also called edge effects. It
    has to do with the generation of development reaction
    products at the transition of a high and low density area.
    Right at the edge of a high density area there are a lot of
    reaction products. They move in the emulsion by diffusion.
    Where conditions are right these products diffuse sidways
    into adjacent areas of the image affecting the way they are
    developed. Right at the edge of a high and low density area
    there is a relatively low concentration of these products so
    the edge tends to be developed more than the body of the
    dense are. Essentially, this draws a line around objects in
    the image. This is a simplification of the effect but will
    give some idea of what is happening.
    The amount and nature of acutance effects depends on the
    developer and amount of development, etc. One of the main
    functions of sulfite is to preserve the developer by
    recombining the reaction products into either active
    developer or to a form which has no effect on development.
    The more sulfite the less acutance effect. Developing agents
    also behave differently. For instance, the reaction products
    of Metol are not active developers. Also, Metol is not very
    sensitive to bromide. Hydroquinone, OTOH, is very sensitive
    to bromide and its reaction products are very active
    developing agents, at least at high enough pH. In D-76 and
    D-23 type developers the pH is too low for either
    Hydroquinone or its reaction products to be active as
    developers, but the Hydroquinone still has the effect of
    regenerating the Metol, which tends to limit adjacency
    effects, and thus, acutance.
    So called high-acutance developers are those which allow
    an exagerated amount of adjacency effect. They are typically
    low sulfite and have a single developing agent. For
    instance, Rodinal is a good acutance developer at high
    dilutions. Developers like D-76 and D-23 begin to produce
    adjacency effects at high dilutions because the
    effectiveness of the sulfite is diminished. At dilutions of
    1 part developer to 3 parts water both of these (and
    Microdol-X and D-25) become acutance developers.
    Although there is not much measurable difference between
    the resolution of high and low acutance developers the
    adjacency effects necessary for high acutance tend to smear
    very fine details so high acutance developers are not a good
    choice where maximum resolution is desired.
    The idea that sulfite somehow dissolves the fine details
    is wrong and is based on a mistaken idea about how sulfite
    functions in the developer.
    Note that the scale of the adjacency effect is fixed. It
    will have relatively large effect on small formats, mainly
    35mm film, and little on larger sizes. At 4x5 it is probably
    undetectable in the image.
    Note also that the conditions for producing acutance are
    not compatible whith those for fine grain. However, a
    compact, sharp, grain pattern will also lend the illusion of
    sharpness. One can prove this effect by printing a sharp
    grain pattern over a print of a blurry negative.
     
    Richard Knoppow, Aug 23, 2005
    #10
  11. Then the formula which say`s 2 grammes per litre, is probably the official
    Adox formula. I had not seen a replenisher formula for this developer before
    either, so a formula for me to file for future reference.
    Thankyou, to all who replied.
     
    Keith Tapscott, Aug 25, 2005
    #11
  12. Keith Tapscott

    UC Guest

    I know all of this, Richard. Perhaps 'definition' is higher with the
    lower sulphite.

    See BJ Photo Annuals from the late 60s-early 70s.
     
    UC, Aug 25, 2005
    #12
  13. Keith Tapscott

    dan.c.quinn Guest

    The sulfite does not dissolve metalic silver.
    I does have some small solvent effect on the
    silver halides.
    If the order of solvency, from chloride, bromide,
    then iodide is, as I think likely, the same as that
    of ammonia and thiosulfate, then the effects of varying
    sulfite levels should be most visable with print paper.
    An all chloride paper such as AZO should, more than
    any other paper, show the effect of changing
    sulfite levels.
    I hope to do some experiments doing just that.
    BTW, you don't happen to know if ascorbic acid acts
    as a silver halide solvent? Dan
     
    dan.c.quinn, Aug 26, 2005
    #13
  14. Keith Tapscott

    nailer Guest

    ascorbic acid will reduce silver salt to metallic silver even at pH 4
    (slowly) and much faster at pH 7 and above.
    Silver nitrate in acidic solution is used in biology to find
    "deposits" of ascorbic acid in plants.



    On 25 Aug 2005 16:06:48 -0700, wrote:

    *RE:Richard Knoppow wrote:
    *>
    *> The action of sulfite is to dissolve a small
    *> amount of the surface of each silver grain.
    *>
    *
    * The sulfite does not dissolve metalic silver.
    *I does have some small solvent effect on the
    *silver halides.
    * If the order of solvency, from chloride, bromide,
    *then iodide is, as I think likely, the same as that
    *of ammonia and thiosulfate, then the effects of varying
    *sulfite levels should be most visable with print paper.
    *An all chloride paper such as AZO should, more than
    *any other paper, show the effect of changing
    *sulfite levels.
    * I hope to do some experiments doing just that.
    * BTW, you don't happen to know if ascorbic acid acts
    *as a silver halide solvent? Dan
     
    nailer, Aug 26, 2005
    #14
  15. Keith Tapscott

    UC Guest

    That's what he meant.
     
    UC, Aug 26, 2005
    #15
  16. Thanks for pointing out the error, I left out the word halide :-(.
    The point of my post was as you point out, that sulfite does not
    dissolve metallic silver but rather has an effect on the undeveloped
    silver halide. This can affect the way the halide builds into metallic
    silver crystals as it develops buth the "salt effect" that is the
    reduction of emulsion swelling from large amounts of sulfit is also an
    important factor in fine grain development.
     
    Richard Knoppow, Aug 29, 2005
    #16
  17. Thankyou to all who replied to this thread.
     
    Keith Tapscott, Sep 1, 2005
    #17
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