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  1. #11

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    One shot fix is pretty wasteful. I use two bath fixing for both film and papers, and I test the first bath with KI solution to determine when to toss it.

  2. #12
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    Quote Originally Posted by dancqu View Post
    I don't test for the amount of time needed to clear. I test for
    the amount of chemistry needed to clear within some fixed
    time; currently 4 minutes. Recall I use fixer one-shot.

    Test are done with 5x7 sheets, with a water presoak. More of
    a real world test at least for those who water stop. The ST-1
    test will produce a silver sulfide stain if fixing is inadequate;
    silver left in the emulsion. I believe a full wash is needed
    do to residual fixer will carry some little silver.

    BTW, films and papers vary in the amount of fixer and
    time required. Dan
    Dan;

    Your last paragraph is the most fundamental and telling comment of all regarding fixation and this is why I recommend testing.

    However, your first part is indicative of conditions so at variance with most everyone else that it skews both your fixation and wash conditions badly from the rest of us who use "normal" dilutions. This is why I have differed with you with respect to fix and wash conditions and have suggested tests.

    Using dilute fixers and long times will change most all facts and figures and therefore will not be representative.

    A "normal" fix used for short times will still alter and extend wash times over a dilute but longer fix, but the dilute fix may not fix properly or wash properly. This again varies from film to film and paper to paper.

    A high iodide film with a dilute fix can sometimes fail the Sodium Sulfide test due to the formation of a pure Silver Iodide ppt which is sluggish to react with the Sulfide test solution. It does react, but ever so slowly due to the pKsps involved and can give a false negative at first appearance. It is doubly difficult to see in film and is rare in paper today except in AgCl/I emulsion papers which do exist. The failure is much rarer in papers though as Iodide is usually very low.

    PE

  3. #13
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    Quote Originally Posted by Kirk Keyes View Post
    One shot fix is pretty wasteful. I use two bath fixing for both film and papers, and I test the first bath with KI solution to determine when to toss it.
    I think the dilution is 1:9 so for 250ml of working fix that takes 25ml of concentrate, means a 1L bottle of fix is good for about 40 rolls. You mix it up and keep it, it's good for about 40 rolls..... It depends on your workflow, I haven't made prints in nearly 25 years, and unless I win the lotto, I probably will not reopen the full darkroom ever again. These days I shoot and process the occasional roll, but because I also shoot digital, and most of the shooting these days is digital, there is a pretty good chance the chemistries will expire before I use them all. This past summer, the weather was so crappy (we had precipitation 5 days out of 7 from November of 2007 right through until now, only 4 weekends where at least one day was dry, and always a day I had some kind of commitment or another. Over that period I had less then 100 shots on digital and no film at all.

  4. #14
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    It is pretty hard to make a 1:9 fixer for film that can be reused with any degree of capacity. 1:9 is pretty dilute for any solution of hypo.

    PE

  5. #15
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    Quote Originally Posted by Photo Engineer View Post
    It is pretty hard to make a 1:9 fixer for film that can be reused with any degree of capacity. 1:9 is pretty dilute for any solution of hypo.

    PE
    Which is why I use it one shot, now it is Ilford Rapid Fixer, so maybe if one was using hypo it would not work as well.....

  6. #16
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    At 1:9, 60% hypo would leave you with 60 grams of ammonium hypo in 1 liter. It needs more kick than that to do a decent job in a reasonable time. With extended times you are right.

    PE

  7. #17

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    Quote Originally Posted by Kirk Keyes View Post
    One shot fix is pretty wasteful. I use two bath fixing for
    both film and papers, and I test the first bath with KI
    solution to determine when to toss it.
    Not wasteful, that depending upon how dilute, how much
    and often used, and what form it is in.

    I didn't pull very dilute fixer out of thin air. I process single
    tray so the use of very dilute one-shot chemistry fits right in.
    Such information as Eddie Ephraums 1/4 strength paper fix
    and Mr. Gainers and others ounce of concentrate added to
    a tank of developer convinced me that if they can do it I
    can to. So encouraged I've taken very dilute fixer to
    extremes then backed off for sure results.

    I've not used rapid fix for some years now. Having little
    volume and wishing for long term keeping quality I've gone
    to the slow earlier standby sodium thiosulfate. Ilford states
    the capacity of 1ltr Rapid concentrate at 120 rolls of135-36.
    Never did use so little but with fresh concentrate found
    15ml, 1/2 ounce, good for a few films. Later I upped it
    to 20ml due to aging concentrate; dilution, 1:24.

    Single tray processing, a big space saver. A second tray
    is needed for a hold/soak. THE 4 minute fix follows a very
    dilute one shot developer, NO stop. One or a few at same
    time prints may be done. All in all quite similar to one-
    shot tube processing but more convenient. View the
    print as it develops.

    I find the method a gas. Tests precede processing. No
    during or post processing tests to do. Known chemistry
    strengths allow consistency. No rebottling. Save space.
    Developer and fix, down the drain each or a few prints.
    The very dilute fix will wash out with less water. Dan

  8. #18
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    Quote Originally Posted by Photo Engineer View Post
    At 1:9, 60% hypo would leave you with 60 grams of ammonium hypo in 1 liter. It needs more kick than that to do a decent job in a reasonable time. With extended times you are right.

    PE
    Your right, this is what I get for typing without checking my notes, for films it's 1:4 so for a 250ml tank it's 50ml of concentrate, so 20 films per litre, could reuse it, I guess, but then you need to keep track of how many rolls through the fixer bath, or use replenishment, it ends up being either keeping track of a lot of bottles or doing a lot of extra math.......
    Paul Schmidt
    See my Blog at http://clickandspin.blogspot.com

    The greatest advance in photography in the last 100 years is not digital, it's odourless stop bath....

  9. #19

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    Quote Originally Posted by wogster View Post
    but then you need to keep track of how many rolls through the fixer bath, or use replenishment, it ends up being either keeping track of a lot of bottles or doing a lot of extra math.......
    No need to do any math or keep track of anything with two bath fixing. You only need to test the first bath after every use. It takes a few seconds to add a bit of KI solution to the fix and see if it forms a precipitate. If it does, you dump the first fix bath, move/relabel the second fix bath into first bath postition, and then prepare a new second bath. Take your fix time with your fixer and divide by two and use each bath for that period of time.

    Not a lot of extra math.

    Dan - where are you? And when are we Oregonians going to get together and meet?

  10. #20
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    Quote Originally Posted by Kirk Keyes View Post
    No need to do any math or keep track of anything with two bath fixing. You only need to test the first bath after every use. It takes a few seconds to add a bit of KI solution to the fix and see if it forms a precipitate. If it does, you dump the first fix bath, move/relabel the second fix bath into first bath postition, and then prepare a new second bath. Take your fix time with your fixer and divide by two and use each bath for that period of time.

    Not a lot of extra math.
    No, but it would mean needing to store 3 bottles of fixer (bath one, bath two, concentrate) plus the bottle of KI solution. When the darkroom is the kitchen sink, and you have a plastic tote with all the equipment and supplies in it between uses, having to keep extra bottles is a chore I would rather not have to deal with. Plus, I don't shoot a lot of film, maybe a roll or two a month, working strength solutions don't last that long unless the bottles are right full and tightly capped. As is once the concentrate is open it needs to be used within 6 months, at maybe 20 rolls a year, it's not really that wasteful. I have a couple of 500ml bottles, I buy 1L a year and split it among the two bottles, so it's whether the concentrate is runs out, before it expires.....Do the same with developer, have a 1L accordion bottle half filled with glass beads, keep half in there and half in a 500ml full bottle, buy 1L a year.....
    Paul Schmidt
    See my Blog at http://clickandspin.blogspot.com

    The greatest advance in photography in the last 100 years is not digital, it's odourless stop bath....

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