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  1. #21
    ozphoto's Avatar
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    Whilst mixing fresh fixer every time, may be a good idea, would it have helped in this particular situation? The entire 5L mix appears to have been "off" (for want of a better description ), so even though I may have mixed it fresh - I would have got the same result, unless I'd performed the clip test first.

    And yes, I'm in the "re-use my fixer" camp and perform a clip test prior to processing my films - anything longer than 3 mins, gets disposed of and a new batch mixed.

  2. #22

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    Quote Originally Posted by ozphoto View Post
    Whilst mixing fresh fixer every time, may be a good idea, would it have helped in this particular situation? The entire 5L mix appears to have been "off" (for want of a better description ), so even though I may have mixed it fresh - I would have got the same result, unless I'd performed the clip test first.

    And yes, I'm in the "re-use my fixer" camp and perform a clip test prior to processing my films - anything longer than 3 mins, gets disposed of and a new batch mixed.
    Of course, you are correct, Nanette. I was getting a bit off-topic there, distracted by the discussion about whether to use fixer one-shot or not. Just wanted to point out that it works just fine without waste.

    As to the OP's problem. If indeed he has a batch of fixer that won't fix, the only thing to do is get some more. Freestyle seems willing to replace it if it is defective and he has already re-fixed the negatives in question. A clip test of the fresh fix would have indeed turned up the problem, but this seems extremely rare. I only clip test fresh fix if I'm using a weird dilution and need to determine fixing time, never just to see if the fixer is working or not...

    Best,

    Doremus

    www.DoremusScudder.com

  3. #23
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    Quote Originally Posted by Doremus Scudder View Post
    Of course, you are correct, Nanette. I was getting a bit off-topic there, distracted by the discussion about whether to use fixer one-shot or not. Just wanted to point out that it works just fine without waste.

    As to the OP's problem. If indeed he has a batch of fixer that won't fix, the only thing to do is get some more. Freestyle seems willing to replace it if it is defective and he has already re-fixed the negatives in question. A clip test of the fresh fix would have indeed turned up the problem, but this seems extremely rare. I only clip test fresh fix if I'm using a weird dilution and need to determine fixing time, never just to see if the fixer is working or not...

    Best,

    Doremus

    www.DoremusScudder.com
    I've often wondered about using one-shot myself, but the workflow I currently have is giving me good results. Having said that though, I am tinkering with the idea of the 2-bath solution. (Certainly wasn't my intent to knock your method on the head Doremus - was trying to point out to others, that in this actual instance, a one-shot method would have failed as well, and that the suggestion of a clip test for fixer, is an excellent way to determine its viability. )

    I must admit that the next time I'm in the darkroom, it will be a fresh mix for all the films I'm processing, simply because I'm away for long periods of time, and the used fixer might not stand the test of time quite as well as I'd like. (Does that count as one-shot?)

  4. #24
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    Quote Originally Posted by Doremus Scudder View Post
    In order to have enough solution for smaller amounts, I simply mix a weaker dilution. Rapid fixers work fine for film in the so-called "print" dilution (1+9 for Ilford products) and higher. For just a few sheets I mix rapid fixers 1+19.
    This is exactly the technique I warned against and I will give you the reason why:
    1. Fixing is a competition between AgBr/AgI and the complex of Silver with the fixer, usually Thiosulfate.
    2. The balance between these two is governed by the solubility product of AgBr/AgI and the complex stability constants of the various Silver Thiosulfate complexes.
    3. Note that all soluble Silver complexes contain several molecules of the fixer, which means the concentration of fixer goes in with an exponent of 2-5.
    4. A low concentration of fixer will therefore shift the balance strongly towards AgBr/AgI and those Silver complexes, which contain only one or two molecules of Thiosulfate. Note, that these are insoluble, i.e. they will remain in your film. And they are not archival!
    5. This means you will end up with retained silver ions, regardless of how long you fix and what your clip test tells you.


    And this is the reason why I advise against one-shot fixing: it becomes expensive, people start diluting their fixer, and archival stability goes out the door. Using two bath fixing with full strength fixer as described by Haist (and many others) is cost effective and avoids exactly these problems.
    Trying to be the best of whatever I am, even if what I am is no good.

  5. #25
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    Good stuff here. Thanks. Most of my developing work is pretty basic and I don't usually stray to far from the directions unless I am doing N+1 or N-1 developing. I always dilute according to the directions on the bottle or package and don't dilute beyond that point.

    Interestingly I have done clip tests in the past, whenever I experimented with a new fixer. But I never thought to use it whenever I started a new batch of a fixer I regularly use. In my case doing a clip test before starting a new batch of fixer would have caught my problem before I had film in the tank. It is a pretty quick and simple process so I think I'll incorporate it in the future when I mix a new batch of dry, or start a new bottle of liquid.

    You learn something new everyday!

    I use 3 different fixers. When I started with each fixer I did clip tests to establish a fix time for my use. Once those clip tests had been done I have not re-done them. Each fixer is mixed at the time of developing except the dry powder fixer. That one is mixed and makes one gallon which is then used without any dilution. None of the fixers I use are terribly expensive so I have always disposed them after I used them fresh and have not tried to re-use any of them. Once I had established a clear time and then multiplied that by 2.5 I felt comfortable and never considered that my fix may not have been archival.

    I have never tried a two bath fix so I will have to research that to see if that helps. I do have one question about it though. In my case, if I had been doing two bath fixing, and one bath was not working, I may have been fooled into believing that my fixing procedure was working correctly when it really wasn't. If I were fixing 4x5 or 8x10 in a tray then I may see the results and catch the problem. But in a daylight tank, you wouldn't know if your fixer was working until you had washed and removed the film for drying. Am I wrong here or is there something I'm missing?

  6. #26
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    Quote Originally Posted by Pioneer View Post
    I have never tried a two bath fix so I will have to research that to see if that helps. I do have one question about it though. In my case, if I had been doing two bath fixing, and one bath was not working, I may have been fooled into believing that my fixing procedure was working correctly when it really wasn't.
    Two bath fixing is an economical way of fixing many films/prints with a limited amount of fixer yet achieving archival results. You basically start with two fixer bathes, and always fix first in bath 1, then in bath 2. After a few rolls of film or sheets of paper you discard bath 1, use bath 2 as the new bath 1 and mix a new bath 2.

    But think of this: most studies on archival fixing were done when acidic fixers based on Sodium Thiosulfate were on vogue. These fixers were slow and weak, and difficult to wash out compared to modern rapid fixers! Using two bath fixing with modern rapid fixers is most likely overkill, but could serve as backup and insurance against over-used, over-aged or otherwise ineffective fixer. It is more economical, more effective, and less prone to failure than using one fixer bath single shot.
    Quote Originally Posted by Pioneer View Post
    If I were fixing 4x5 or 8x10 in a tray then I may see the results and catch the problem. But in a daylight tank, you wouldn't know if your fixer was working until you had washed and removed the film for drying.
    That's why clip tests are recommended. Note there are also simple test procedures for retained silver, so if you are uncertain about past film rolls, you can still find out whether you need to refix them before bad things happen.
    Trying to be the best of whatever I am, even if what I am is no good.

  7. #27
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    Thanks Rudeofus. I'll check on the test procedures for retained silver and incorporate that into my process.

    I have been photographing and developing for awhile but it seems there is always something else to learn, or to be reminded about. This has been the case here and this has been a great little thread for me. I really appreciate everyone's time and their help.

  8. #28

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    "That's why clip tests are recommended"
    Allright but do you have to prewet your clip in plain water before you dip it into the fixer or can you use a dry clip?
    I've heard that to get an accurate result you have to use a "wet" clip...

    "This is exactly the technique I warned against"
    I fully agree. The ONE time I had problems with neg fixing was when a "pro" (he did Helmut Newton's darkroom work in the 80's...) advised me to fix my negs in a 1+9 solution (instead of the usual 1+4).

    He said he got "nicer negs", me I got brown-stained unfixed negs...

  9. #29
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    Quote Originally Posted by Pat Erson View Post
    "That's why clip tests are recommended"
    Allright but do you have to prewet your clip in plain water before you dip it into the fixer or can you use a dry clip?
    I've heard that to get an accurate result you have to use a "wet" clip...
    Clip test is not an accurate test anyway since all it tells you is whether and in which time frame fixer dissolves enough silver ions to make the test clip look transparent. Theoretically it tells you nothing about retained silver or how long it takes from clearing to archival fixing.

    If you start with a dry test clip, the fixer will take longer to clear the test clip, so chances are you will overestimate the time you need for fixing. On the other side, the time difference between dry clip and prewet clip should be less than half a minute. IMHO it really doesn't matter. Give the fixer an extra minute if you want to be sure. Or use one of these commercial tests for retained silver to verify that your fixer procedure, whatever it is, works reliably.
    Trying to be the best of whatever I am, even if what I am is no good.

  10. #30

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    Quote Originally Posted by Rudeofus View Post
    This is exactly the technique I warned against and I will give you the reason why:
    1. Fixing is a competition between AgBr/AgI and the complex of Silver with the fixer, usually Thiosulfate.
    2. The balance between these two is governed by the solubility product of AgBr/AgI and the complex stability constants of the various Silver Thiosulfate complexes.
    3. Note that all soluble Silver complexes contain several molecules of the fixer, which means the concentration of fixer goes in with an exponent of 2-5.
    4. A low concentration of fixer will therefore shift the balance strongly towards AgBr/AgI and those Silver complexes, which contain only one or two molecules of Thiosulfate. Note, that these are insoluble, i.e. they will remain in your film. And they are not archival!
    5. This means you will end up with retained silver ions, regardless of how long you fix and what your clip test tells you.


    And this is the reason why I advise against one-shot fixing: it becomes expensive, people start diluting their fixer, and archival stability goes out the door. Using two bath fixing with full strength fixer as described by Haist (and many others) is cost effective and avoids exactly these problems.
    Rudeofus,

    I'm interested in learning more about why dilute fixer does not fix archivally. I'm no chemist, but I've hashed this out with others on this forum who are and corresponded with the Ilford tech rep about using rapid fixers 1+9 for film. The consensus seemed to be that it worked fine, but that fixing times needed to be extended.

    Certainly, if there is not enough of the thiosulfate ions in solution to achieve complete fixing, there will be residual silver in the film. However, that is just a question of making sure one has enough capacity. I would think that making sure the capacity is not exceeded and extending the fixing time would be enough to ensure that no insoluble silver compounds remained in the film. Much more risky, in my view, is using fixer that is near exhaustion, where lots of insoluble compounds have built up.

    When I first started processing negatives with weaker dilutions, I tested them for residual silver. They passed the test with flying colors. I used the Formulary residual silver test kit. I would think that that would show the residual silver you mention.

    I do agree that two-bath fixing is more economical when processing larger amounts of film, but for just a few sheets, I find a one-shot approach the best solution.

    Best,

    Doremus

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