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  1. #11
    Ole
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    Quote Originally Posted by Marco B View Post
    Acidic fixer?? Aren't fixers always basic? Well, maybe not, but what kind or make of fixer are you suggesting. Most brands seem to be simply ammoniumthiosulphate, which is basic.
    Traditionally, fixers were always acidic.

    "Most brands" are ammonium thiosulfate plus some othe chemicals like sulfite, bisulfite, and so on to improve keeping properties and ensure the specified pH.

    Acidic rapid fixers (or any rapid fixer which has been acidified through the addition of a little acid) tend to bleach silver ever so slightly, which is precisely what will remove the pink cast in the highlights that you get when an inproperly fixed print has been exposed to light.

    So what I suggested was not only a refix in new fixer, but a slight bleach as well.
    -- Ole Tjugen, Luddite Elitist
    Norway

  2. #12

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    Quote Originally Posted by Dave Miller View Post
    Quote: "I know there are specialized products for cleaning trays. Can anyone recommend something?"

    Soap, water, and elbow grease.
    Those stains are silver. Dave's elbow grease method will work sometimes, but it depends on the tray and you'll never get it all. There is an easier way that will not cost a fortune. Pour some bleach (potassium ferricyanide) into the tray and let it sit for a while. That will return the silver to a silver salt which can then be dissolved and carried away with some fixer.

  3. #13

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    Quote Originally Posted by ath View Post
    Polywarmtone needs strong, fresh fixer.
    Fresh is the only way I use fixer; real fresh one-shot.
    Small volumes of very dilute chemistry using a tray
    rather than a tube make single tray processing
    a snap. About 1:24. A use then dump. Forte's
    paper is fixed in 3 minutes. Dan

  4. #14
    Photo Engineer's Avatar
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    Retained developing agent will gradually oxidize and cause a colored stain. The color depends on the developing agent(s) used.

    Acid alone will not remove them. Actually a sulfite bath is best because sulfite reacts with oxidized developers and enables them to be washed out. Many people forget that this chemical is an aid to removal or prevention of retained developer stains.

    PE

  5. #15

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    if you have a dedicated developer tray is the stain something you really need to worry about? At the local art school I have seen developer trays that were nearly black with stain.
    Emancipate yourselves from mental slavery;None but ourselves can free our minds. - Bob Marley

  6. #16
    Vaughn's Avatar
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    I usually see the dreaded pink stain when students just toss their prints in the fixer and go print another one -- prints will sit there in the fix and where two prints are touching, there is little "fixing" going on.

    We scrub our SS trays every time we replace the developer. Otherwise the silver gets on the prints when the prints rub on the bottom of the tray (black marks).

    Vaughn

  7. #17

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    Quote Originally Posted by Vaughn View Post
    I usually see the dreaded pink stain when students just toss their prints in the fixer and go print another one -- prints will sit there in the fix and where two prints are touching, there is little "fixing" going on.

    We scrub our SS trays every time we replace the developer. Otherwise the silver gets on the prints when the prints rub on the bottom of the tray (black marks).

    Vaughn
    But even with the scrubbing, don't the trays eventually get dis-colored with a stain that won't scrub off and doesn't get on the prints?
    Emancipate yourselves from mental slavery;None but ourselves can free our minds. - Bob Marley

  8. #18

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    Quote Originally Posted by Ole View Post

    Acidic rapid fixers (or any rapid fixer which has been acidified
    through the addition of a little acid) tend to bleach silver ever
    so slightly, which is precisely what will remove the pink cast in
    the highlights that you get when an inproperly fixed print has
    been exposed to light.

    So what I suggested was not only a refix in new fixer,
    but a slight bleach as well.
    Very dilute Farmers Reducer may be a good cure. Odd the
    hue is red-ish. In testing I've slightly to grossly under-fixed
    a few papers and have been left with hefty mustard browns
    to pleasant cream/tan warmth; one paper a very light gray.

    Slavich has always come out clean. It has yet to be tested
    with so little fixer so as to produce any color. Kentmere's
    Bromide on the other hand takes on an ugly dark brown
    -ish hue when tested with that same minimum amount.
    Time, temperature, and agitation all being the same.

    Counting square inches is not a method I'd use in
    determining a fixer's exhaustion. And not just because
    of the varying amounts needed by this paper or that.
    Conditions of use and other factors vary. Dan

  9. #19
    Marco B's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    Retained developing agent will gradually oxidize and cause a colored stain. The color depends on the developing agent(s) used.

    Acid alone will not remove them. Actually a sulfite bath is best because sulfite reacts with oxidized developers and enables them to be washed out. Many people forget that this chemical is an aid to removal or prevention of retained developer stains.

    PE
    Thanks all for the comments, but I think Photo Engineer solved it. I'm pretty sure I have not had a "fixer" type issue. I test my fixer regularly, and it wasn't old. Nor did fresh fix remove the stains.

    Actually, since I had been using a brush, I am now suspecting, as PE suggested, that the stains are caused by oxidized developer. During the printingsession, the brush had been lying around and of course the developer is bound to oxidize as hell in this situation. It is consistent with another observation: the stains are getting worse with the later on the day I printed them.

    In addition, before I read PE's response, and since the prints were ruined anyway, I decided to throw them in a bath of regular house hold "soda", based on a hunch similar to PE respons. After some six hours soaking, most of the staining was gone. The hydroxide anions probably do something similar to the sulphite, suggested by PE, breaking down and reacting with the oxidized developer.

    Next time I use a brush to develop prints, I will thoroughly rinse my brush after each print, preventing oxidized developer build up on the brush.

    Actually, just one last question:

    - How do I create a regular sulphite bath as PE suggested? What chemicals do I need and where can I get them?
    Last edited by Marco B; 12-03-2007 at 04:26 AM. Click to view previous post history.

  10. #20
    Marco B's Avatar
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    Quote Originally Posted by fschifano View Post
    Those stains are silver. Dave's elbow grease method will work sometimes, but it depends on the tray and you'll never get it all. There is an easier way that will not cost a fortune. Pour some bleach (potassium ferricyanide) into the tray and let it sit for a while. That will return the silver to a silver salt which can then be dissolved and carried away with some fixer.
    Although your suggestion may solve part of the issue, it's unlikely to remove all.

    Bleach converts silver (Ag) to two substances:
    - Silverbromide (Ag+Br-)
    - Silverferrocyanide (Ag+Fe(CN)64-)

    Silverbromide is of course easily dissolved in fixer, which is how fixer works. However, despite most metal-ferrocyanide compounds being vulnerable in alkaline conditions (just throw a cyanotype or blue toned print in fixer or a soda solution! , also see this excellent article by Wilco Oelen: http://woelen.scheikunde.net/science...ners/toner.pdf), silverferrocyanide seems to be pretty stable. It won't be removed in fixer.

    You can simply test this by totally bleaching a print, and throwing it in fixer. Although the light yellow image bleaches somewhat (removal of AgBr), it is not possible to completely remove it in fixer (most likely remaining Ag+Fe(CN)64-), nor does an alkaline soda solution remove it... would have been kind of nice if this would work and you would be left with bright white paper... could be used as a creative measure, partially obliterating photo's.
    Last edited by Marco B; 12-03-2007 at 04:56 AM. Click to view previous post history.

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