recycling fix

Discussion in 'B&W: Film, Paper, Chemistry' started by Jarvman, Jan 27, 2008.

  1. Jarvman

    Jarvman Member

    Messages:
    736
    Joined:
    Sep 9, 2006
    Location:
    Cardiff, Uni
    Shooter:
    Multi Format
    Would you ever pour the fix you've just devved a film with into a tray for fixing paper? It seems like a waste to chuck it after one film. It can't be spent that quickly can it?
     
  2. pentaxuser

    pentaxuser Subscriber

    Messages:
    8,104
    Joined:
    May 9, 2005
    Location:
    Daventry, No
    Shooter:
    35mm
    I can't say why fix used for film can't or shouldn't be switched to paper but it seems it shouldn't be. However fix for film development can be used again. It doesn't have to be thrown away after one film so, NO, it isn't spent that quickly.

    pentaxuser
     
  3. jim appleyard

    jim appleyard Member

    Messages:
    2,131
    Joined:
    Nov 21, 2004
    Shooter:
    Multi Format
    IIRC, some fixers require one dilution for film, one for paper.

    I always used two batches anyway as the fix in the paper tray collects airborne particles and I don't want them on my film.
     
  4. Jarvman

    Jarvman Member

    Messages:
    736
    Joined:
    Sep 9, 2006
    Location:
    Cardiff, Uni
    Shooter:
    Multi Format
    other way around, i've poured the fix from my film into a bottle ready for some printing tomorrow. I've been using the same dilution for film and paper.
     
  5. Neanderman

    Neanderman Member

    Messages:
    575
    Joined:
    Mar 22, 2004
    Location:
    Ohio River V
    Shooter:
    Large Format
    This is because of the iodide content of film. Iodide greatly slows the activity of fixer such that if you use the same fixer for both film and paper, you run the risk of not fully fixing the prints, which is death for a print.

    I can't remember the exact details but they are outlined in Haist.

    I'm sure PE can fill in the missing details.

    Ed
     
  6. Jarvman

    Jarvman Member

    Messages:
    736
    Joined:
    Sep 9, 2006
    Location:
    Cardiff, Uni
    Shooter:
    Multi Format
    How many films do you generally process with one batch of fix and how much would you increase the time by as it gets weaker? I've always thrown it away and thought it was wasteful but haven't thought about asking whether to use it over again before. Though come to think of it in school this is what we used to do, pour the stuff back into a bottle for re-use.
     
  7. Akki14

    Akki14 Member

    Messages:
    1,873
    Joined:
    Feb 2, 2007
    Location:
    London, UK
    Shooter:
    4x5 Format
    Drop a bit of film in the fix and time how long it takes to clear in fresh fix. When it takes twice as long to clear as it did originally, then you can dispose of the fix (as long as you're keeping fix for film separate from paper)
     
  8. Tom Hoskinson

    Tom Hoskinson Member

    Messages:
    3,879
    Joined:
    Mar 7, 2004
    Location:
    Southern Cal
    Shooter:
    Multi Format
    No, I use a 2 bath fixing system for fiber paper prints. I use fresh alkaline fixer for both baths. The paper fixes quickly without overfixing and washes out easily to archival standards.

    For film, I also use fresh alkaline fixer and then discard (recycle) it afterwards. Fixer is inexpensive and I'm not willing to risk contamination of my fiber prints.
     
  9. jp80874

    jp80874 Subscriber

    Messages:
    3,490
    Joined:
    Jul 28, 2004
    Location:
    Bath, OH 442
    Shooter:
    ULarge Format
    Why not check the used fixer with a drop or two of “Hypo Chek” or what ever it is called in England? It is a liquid that "tests for exhaustion due to silver saturation".

    I develop film with Rollo Pyro in a Jobo CPP-2. The instructions call for a single usage of fixer. At school they use a five gallon drum of fixer. The students develop in daylight hand tanks. When they are done with fixer it is poured back in the drum. Supposedly the Lab Technician periodically checks to see if a fresh drum is needed.

    John Powers
     
  10. bdial

    bdial Subscriber

    Messages:
    5,310
    Joined:
    Jan 2, 2005
    Location:
    Live Free or
    Shooter:
    Multi Format
    Using Hypo Chek is a good method, but you should draw off a sample to use for the test and discard afterward, as it will weaken the fix otherwise. (search should show up PE's comments on this).
    With film I check the film at 1/2 the minimum time stated on the fixer's data sheet. If the film is clear (usually) then I simply fix for the minimum stated time. Otherwise I double the clearing time, up to the max stated on the data sheet. That is, the clearing time should never exceed the 1/2 max time stated in the data sheet.

    It's wasteful and polluting to dump the fixer after one use, either for film or paper, after all, you are dumping heavy metals (silver) into the waste stream. Or in my case with a septic system, into ground water that I might eventually drink. Thanks but no thanks.
     
  11. Tom Hoskinson

    Tom Hoskinson Member

    Messages:
    3,879
    Joined:
    Mar 7, 2004
    Location:
    Southern Cal
    Shooter:
    Multi Format
    Yup! That's why I recycle fix and don't dump it.
     
  12. Neanderman

    Neanderman Member

    Messages:
    575
    Joined:
    Mar 22, 2004
    Location:
    Ohio River V
    Shooter:
    Large Format
    Again, it's the iodide that is used in hypo check.

    Ed
     
  13. Tom Hoskinson

    Tom Hoskinson Member

    Messages:
    3,879
    Joined:
    Mar 7, 2004
    Location:
    Southern Cal
    Shooter:
    Multi Format
    In my lab (at work) we still wet process a lot of Xray film and Kodak Tech Pan (we have freezer full of Tech Pan). We send all of our used fixer to a silver recovery sevice.
     
  14. BobNewYork

    BobNewYork Member

    Messages:
    1,067
    Joined:
    Jan 1, 2008
    Location:
    Long Island,
    Shooter:
    Medium Format
    Even though I use the same fixer and dilution for film and paper I've never mixed them - not for any particular reason, I just haven't. reading Tom's post, I'm glad I didn't now. (I'd rather be lucky than good!)

    My largest film tank takes 1.5 litres of solution so I keep a one litre and a half litre on hand. In use, I pour in fixer from the litre bottle and at the end return it to top off the half litre, pouring the balance into the"ex-litre" bottle. This way the entire one and a half litres gets the same usage. A while back, I ran tests with a single litre - clearing times and hypo check and found that the clearing time doubled after 21 films. On this basis I fix 20 films in my litre and a half before replacing the batch.
     
  15. jp80874

    jp80874 Subscriber

    Messages:
    3,490
    Joined:
    Jul 28, 2004
    Location:
    Bath, OH 442
    Shooter:
    ULarge Format
    bdial,

    Assuming that comment was for me, the dump after one use is in the Rollo Pyro manufacturer's (Bostick & Sullivan) instructions. The same instructions say use only 350ml of fixer for five sheets of 8x10. At this point the fixer is also heavily loaded with pyro stain that would do nothing positive for fixing prints of snow scenes. "Dump" in my case, means dump the 350ml plus the first two 450ml rinses of the Jobo Expert tank into a gallon jug. When I accumulate three or four gallons, I take them to the University where I still take courses at age 67. The University encourages students with home darkrooms to use the school's silver recovery system to "help save the environment". I also have a well upstream from our septic system.

    John Powers
     
    Last edited by a moderator: Jan 28, 2008