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  1. #11
    Photo Engineer's Avatar
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    Dan;

    I've heard the same, but never inside EK. The interesting thing is that if it does, the means is unclear except for the following possibility...

    Just as Sodium Sulfite -> Sodium Sulfate in hypo solutions, thereby protecting hypo from oxidation, the Selenite might do the same thing and the Selenate is less toxic, but IDK by how much. And, since I don't want to work with it, I have not run, nor don't intend to run the tests. I was exposed to lots of Selenium Dioxide in grad school making alpha-diketones. After listening to stories at EK and finding their reluctance to get into Selenium sensitization and Selenium sensitizing dyes, I am a bit too negative about Se.

    PE

  2. #12
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    Quote Originally Posted by Claire Senft View Post
    I have purchased items from Laabs also.

    Who would lie about being in Milwaukee?
    A Chicagoan in hiding...EC

  3. #13

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    I MADE A BIG MISTAKE:

    I originally asked for information on Sodium Selenite. This is what I wanted.

    THE FORMULA THAT I LISTED WAS ERRONEOUS:

    IT SHOULD READ AS FOLLOWS:

    water 500ml
    Ammonium Thiosulfate (50% sol.) 100ml
    Sodium Sufide 30grams
    Sodium Selenite 4grams
    water to make 1 liter

    I know very little about chemistry.
    Does this appear to be more like KRST than the incorrect version?
    Claire (Ms Anne Thrope is in the darkroom)

  4. #14
    Photo Engineer's Avatar
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    Not to be picky, but the Sodium Sulfide has a very very strong odor of rotten eggs. Kodak toner does not IIRC. So, I doubt if this is exactly like the Kodak product. The solution described above should be alkaline which might repress the odor, but the solid would stink quite a bit.

    IDK, just a thought. I don't know the KRST formula and never did, being very disinterested in compounding selenium formulas.

    PE

  5. #15

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    Claire, KRST is a straight selenium toner. The formula you provided has sulfur as well, which makes it more like the old Kodak Polytoner. Flemish toner also combines sulfur and selenium. If that's what you're looking for, consider buying Moersch Carbon Toner from Freestyle, now that they carry it. It contains sodium selenite and sodium sulfide.
    Last edited by psvensson; 09-19-2008 at 11:14 AM. Click to view previous post history. Reason: expanded answer

  6. #16

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    The only published Kodak selenium toner formula I've come across is T-55.

    T-55 selenium toner

    Stock solution
    sodium sulphite, anhydrous - 150g
    selenium powder - 6g
    ammonium chloride - 190g
    water to make 1L

    Dissolve the sodium sulphite in 750ml of hot water. When completely dissolved add the selenium powder and boil for approx 30 minutes*. Any remaining insoluble matter must be filtered off. When cool add the ammonium chloride and stir until completely dissolved. Then make up to 1L with cold water.

    For use dilute 1:5, 1 part T-55 to 5 parts water.

    *The heating (boiling) of selenium is a very hazadous procedure and something I would certainly not recommend with out access to a fully working/tested fume cupboard. Something I once had access to when I used to prepare this solution.

    Also note that this is not the same as KRST.
    Last edited by Trevor Crone; 09-19-2008 at 01:37 PM. Click to view previous post history. Reason: spelling

  7. #17

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    Quote Originally Posted by Claire Senft View Post
    I MADE A BIG MISTAKE:

    {snip}

    I know very little about chemistry.
    Perhaps you should think twice about making something like this. The raw constituents are not as nice and safe as most other photo chemicals.

    Quote Originally Posted by Claire Senft View Post
    Does this appear to be more like KRST than the incorrect version
    I think this is similar to what Kodak used to call "Polytoner" - it was a mix of selenium and sulfide toners.

  8. #18

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    A safer way to make something like this would be to take KRST and add a bit of sodium sulfide and see how that goes. It's still going to be stinky, but much less hazardous to do.

  9. #19
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    Quote Originally Posted by Photo Engineer View Post
    There is a big difference between Na2S and Na2SO3 (IDE vs ITE) and Na2Se and Na2SeO3 (IDE vs ITE). The latter two are far more toxic of course, and the IDES are far less stable and more toxic than the ITES. Beware the IDES of Selenium and March both, or you can end up like big Julie with a pain in the portico.

    These chemicals will get to you right in the rotunda! Then you lose your hair and any gender associated attributes and it goes downhill after that.

    Beware of a garlic odor on your breath. By that time it is too late usually.

    PE

    I've not experienced Selenium toner, but PE is right about the odour of selenium compounds. I've been a fan of old valve (Tube) equipment since I was young, and some of them had selenium recifiers in there.
    I tried reviving a old piece of kit that had one in that wanted to stay dead. The link attached is an indication of what happens when you don't pull the power quick enough. I was lucky and killed the power very quickly before things got anywhere near dangerous

    http://yarchive.net/electr/selenium_rectifiers.html

    It was like cleaning out the rotting bins at the Gilroy Garlic Festival. Google that if you have a strong stomach
    "Flatter Me, and I May Not Believe You. Criticize Me, and I May Not like You. Ignore Me, and I May Not Forgive You. Encourage Me, and I Will Not Forget You."

  10. #20

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    Quote Originally Posted by psvensson View Post
    The formula you provided has sulfur as well,
    which makes it more like the old Kodak Polytoner.
    Kodak Polytoner. That is the one I had in mind and refered
    to in my post # 10. Kodak has/had posted a formula for
    it's home brew replacement.

    Apparently the sulfur contained in older KRST prodution
    accounted for it's 'archival' effects. New, and now for
    some years, the product has been minus that sulfur.
    At least there has been no word to the contrary.

    By all accounts the addition of some little sulfur to
    off the shelf KRST SHOULD restore it's 'archival'
    nature. All interested in the old Kodak Poly
    should do a Google search. Dan

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