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  1. #11

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    Quote Originally Posted by dancqu View Post
    Included in P. Dignan's Classic B&W Formulas is
    another substitute formula from R. W. Anderson.

    Metol 7.5 grams
    Sodium Sulfite anhydrous 100 grams
    Sodium Bisulfite 7.5 grams
    Water to make 1 liter.

    Almost a D-25. Times and results are the same
    as for Microdol-X. The substitute's weight is not
    the same as the packaged. I doubt that sodium
    chloride will reduce the ph while S. bisulfite
    should some little.

    If one would like to go the ultra-fine grain route via
    low ph and without all that chemistry a bicarbonated
    FX-1 or Beutlers should be worth a try. As with the
    substitutes there likely would be a speed hit. Dan
    Yes Dan, I posted R.W.Anderson's substitute formula a long time ago in the APUG recipes section and it caught quite a bit of flack.

    The inclusion of Sodium Chloride is supported by the Microdol-X MSDS.
    Tom Hoskinson
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  2. #12

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    Thanks everybody, for the remarks. But all of them were about grain size. But what about contrast? What happens to the contrast when you increase the dilution/greater dilution?

    In other words, why would one choose a certain dilution? Why go to a greater one, why go to a larger one?

    Cheers again, Mike

  3. #13

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    Quote Originally Posted by michielp View Post
    Thanks everybody, for the remarks. But all of them were about grain size. But what about contrast? What happens to the contrast when you increase the dilution/greater dilution?

    In other words, why would one choose a certain dilution? Why go to a greater one, why go to a larger one?

    Cheers again, Mike

    Michiel,

    contrast is not controlled by dillution but rather by decreasing/increasing development time and agitation.

    G

  4. #14
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    Yes changing dilution will change contrast.

    If you change from say 1+1 dilution to 1+3 and leave time and temp the same, you will change the effective film speed (reduce) and the characteristic curve shape will also be changed. It tends to rise more slowly (longer toe) and depending on film type, you can introduce a marked shoulder into the film at an earlier point. This is what compensation does. The reverse is also true, i.e. reduce dilution from 1+3 to 1+1 or 1+0 and you will tend towards a shorter toe and shorter shoulder at a higher point.
    Percepts,
    An old dog learning new tricks...

    Black and White Landscape Prints

  5. #15

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    Quote Originally Posted by percepts View Post
    Yes changing dilution will change contrast.

    If you change from say 1+1 dilution to 1+3 and leave time and temp the same, you will change the effective film speed (reduce) and the characteristic curve shape will also be changed. It tends to rise more slowly (longer toe) and depending on film type, you can introduce a marked shoulder into the film at an earlier point. This is what compensation does. The reverse is also true, i.e. reduce dilution from 1+3 to 1+1 or 1+0 and you will tend towards a shorter toe and shorter shoulder at a higher point.
    How do these changes affect the contrast? (I guess I'm not well known to the characteristic curve shapes)

    These changes are when the developing time is left the same, while diluting the solution.

    But what if we change the time accordingly as well? Longer time for higher dilution, and vice versa. So what changes can be expected if one changes the dilution and adjusts the developing time accordingly?

  6. #16
    percepts's Avatar
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    the contrast is not altered evenly along the characteristic curve.

    low contrast would be a flatter curve, longer dynamic range accepted onto film but still fits the paper.

    high contrast would be a steep curve, shorter dynamic range fits on film and still fits to paper.

    contrast is usually measured as gamma which is the average steepness of the curve over its central portion but changing dilution affects both toe and shoulder as well so it affects both shadow contrast and highlight contrast and not just overall contrast.

    The variables are endless which is why you have to test for yourself and arrive at something which suits you. i.e. each dev and film combination combined with temp, agitation and how well you metered, will produce different results. So precise consistency is the name of the game when metering and developing film otherwise your test results will be meaningless.

    changing time may remove most of the effect on toe of the curve but typically you will lose separation between zone 0 and zone 1 when you dilute developer unless you alter time and or film speed to compensate. Time may also increase contrast to negate some of the effect on the shoulder. But once again, it all depends on your film and dev combination etc etc.
    Percepts,
    An old dog learning new tricks...

    Black and White Landscape Prints

  7. #17

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    Quote Originally Posted by percepts View Post
    ...I have no definitive answer to that but I have observed that the higher th PH of the developer, the greater the tendancy of the grain to clump. ...
    I can confirm this. Actually I remember that somewhere I have read that this is due to a sort of softening of the gelatine at higher pH so the silver grains are more free to clump together, but I don't know if it's the correct explanation.
    Regards


    Elia

  8. #18
    percepts's Avatar
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    when its gets down to chemistry and no one knows the actual chemical formula of any film or the make up of its gelatin and the vast majority don't know the true chemical formula of the dev they are using or how the reaction process between the unknown film formula and dev formula will take place, its no wonder that there is so much speculation on what any change will do to your results. All you can do is experiment and be very very observant of what happens and keep notes. Film development is not an exact science unless you live and operate inside a vacuum such as a Kodak lab and know exactly what all the parameters are.
    Percepts,
    An old dog learning new tricks...

    Black and White Landscape Prints

  9. #19

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    Mike. Have a look in the standard gallery at Thomas Krebs " Gottingen 1994". Sorry Thomas my key board doesn't have an umlaut and I've forgotten the ACS11? code for it. He used ID11 at 1:5 which is a dilution I hadn't seen mentioned before. Stock or more often 1:1 is the normal ratio. A couple of us remarked on this and he said that he found it useful in high contrast scenes.

    So high dilution ID11 appeared to work for high contrast scenes. Certainly it was an amazing shot and would make ID11 go a long way.

    pentaxuser

  10. #20
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    Diluting a developer that has 80 to 100 grams of sodium sulfite / liter will always increase the apparant grain size because the solvent action of the sulfite ends when the concentration is cut in half. D76 straight will always look smoother than D76 at 1:3.

    At 1:3 you will get an increase in film speed, sharpness and grain.
    Last edited by fhovie; 05-31-2007 at 03:46 PM. Click to view previous post history. Reason: make clearer
    My photos are always without all that distracting color ...

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