Old fixer in powder form expired ?

Discussion in 'B&W: Film, Paper, Chemistry' started by jfdupuis, May 11, 2009.

  1. jfdupuis

    jfdupuis Member

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    Hi,

    I dig into the chemistry closet of my photo club and it seems that we have lot of that Agfa rapid fixer. I'm using this one for prints for a while, but I just use it for film recently and I guess there is a problem with it. After fixing my first roll with this one following the 2-3 mins recommendation, I had kind of yellowish light stain on my dry negative. Another member said that this way because the film was under fix.

    Thing is that the fixer was freshly mixed from the powder bag. I mixed it myself, so I'm pretty sure it was mixed properly. I check the clear time and obtained a 3 minutes clear time. This is about the recommended time, which should be more than twice the clear time. I also check with fixer tester stripes, which test for silver concentration and the pH. These testing stripes tell me that the fixer is all right.

    Then, is it possible that this fixer, even in powder form, is expired ?

    Thanks,

    Jeff
     
  2. pgomena

    pgomena Member

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    The rule of thumb is that fix time should be 2X clear time. Agitate in fixer just as you do in developer. Some films take longer to clear than others. I fix all my films for 5 minutes. You can refix and rewash the negatives and they will most likely be fine.

    Some fixers are diluted for use with paper or use shorter fix times for paper, especially RC papers. Fixer usually is used full-strength for film. I've not used your particular fixer, but I'd say your friend was right.

    Peter Gomena
     
  3. clayne

    clayne Member

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    I do the same as pgomena - fix for 5 minutes.

    The fixer sounds fine. The film wasn't T-max was it?
     
  4. jfdupuis

    jfdupuis Member

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    In fact, this second time, I fixed for 8 minutes and it seems that it was still not enough. The film was HP5+ in sheets.
     
  5. clayne

    clayne Member

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    Just dump it then. Don't take risks with fixer. However, if you still have some of the old fixer left over, I'd half the dilution and try again. I'm not a chem expert but it sounds strange that powder form fixer would ever go bad.
     
  6. cmacd123

    cmacd123 Subscriber

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    When I started in the darkroom in the late 1960's the fixing time for film in "regular" fixer was 10 minutes. I recall our Camera club had a large stock of "Ansco Acid Fixer" which came in cans. Those who had money bought "rapid fixer" which came as a liquid - sometimes with a bottle of hardner and fixed in 2-3 minutes.

    I think the "old stuff" is still sold as "Kodak Fixer" in powder form. these days it is in envelopes which may not be as air tight as the cans. The liquid stuff DOES go bad BTW, if you get a yellow precipitate it is past use.