Without a buffer will my developer suffer?

Discussion in 'B&W: Film, Paper, Chemistry' started by David Lyga, Jul 16, 2012.

  1. David Lyga

    David Lyga Subscriber

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    I regularly mix a simple B&W film developer using 1g metol, 3g HQ, only 6g sulfite and 1g carbonate, mono. This does the job well. I ALWAYS use it 'one shot' at a rather high dilution (hence, the carbonate). Doing this, I never experience changes in energy due to the passage of time, even after six months or more (I store in PET plastic, filled to the rim, thus I get away with using such a small amount of sulfite, as this plastic does not 'breathe').

    Should there be a buffer included in my formula? Or is the buffer primarily for a replenishment system? Again, I experience no problems but just want more light on the purpose and function of buffer as relates to proper pH maintenance. - David Lyga
     
  2. Steve Smith

    Steve Smith Subscriber

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    I'm no expert but I think the buffer is to make it alkaline and it would be too acidic without it.


    Steve.
     
  3. David Lyga

    David Lyga Subscriber

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    I think, Steve, its purpose is to maintain the SAME pH. Correct if I am wrong. - David Lyga
     
  4. Michael R 1974

    Michael R 1974 Subscriber

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    Buffering is to maintain a pH with dilution etc. Not all developers are buffered.
     
  5. Kirk Keyes

    Kirk Keyes Member

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    Carbonate has some buffering properties. As it gets neutralized and converts into bicarbonate, it will gain some buffering capacity.
     
  6. Gerald C Koch

    Gerald C Koch Member

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    A buffer is not really needed when a developer is used as a one-shot. The formula that you use is similar to the Beutler formula which contains no specific buffer.
     
  7. Ian Grant

    Ian Grant Subscriber

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    A buffer's more important when a developer is re-used (and often replenished) as it keeps the pH more stable.

    Ian
     
  8. David Lyga

    David Lyga Subscriber

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    That's the confirmation I was seeking. Thank you. - David Lyga
     
  9. Trask

    Trask Subscriber

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    I confess your post has me confused, David. If the developer is mixed as a one-shot, why is the issue of storage being discussed? I can only speculate that you are mixing larger quantities of the chemicals (in the proportions you discuss) in a concentrated solution, then dilute when needed, as with HC-110.

    So I wind up uncertain as to whether a buffer is truly necessary or not.
     
  10. David Lyga

    David Lyga Subscriber

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    No Trask and I think that you just caught me with semantics!
    It is not MIXED one shot but USED one shot. Sorry for the confusion. I mix several liters at one time. - David Lyga