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  1. #21

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    [quote="Annie"]J
    The colour of the image also shifted next to a selenium toned print it has a subtle hint of olive green but still cool and neutral... (But not that sick green of Ilford Warmtone).

    This makes me believe that your toning experiment was a definite success. One of the color changes I have observed in toning kallitypes with a combination of pt/pd has been a slight shift toward green, to a final color I would call olive brown.

  2. #22

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    Good job Annie!

  3. #23

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    Some further ponderings about Pt/Pd toning......

    Subsequently, I have found an older formula that is actually listed as 'Silver Substitution' using precious metal salts. In the listed formula they are using Cobalt Chloride and the text states that the other metal salts are not employed do to reasons of cost. In this formula there is a simultaneous mixing of 2 separate solutions at the time of toning right after development. The first solution is basically Cobalt Chloride & Sodium Citrate the second solution contains Potassium Ferricyanide. Does anyone foresee any obvious problems with substituting Potassium Chloroplatinite for the Cobalt Chloride? My usual concerns..... Explosions, invisible deadly gases, solutions that eat the flesh to the bone in a matter of seconds.

    Oh ....and just curious why we were trying to do this substitution thing in the first place?

    Thanks.

  4. #24

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    [quote="Annie"]Some further ponderings about Pt/Pd toning......


    Oh ....and just curious why we were trying to do this substitution thing in the first place?


    Annie,

    My interest in the substitution was to obtain greater permanence of kallitype prints. By replacing silver metal, whcih oxidizes readily, with gold, platinum or palladium you should in theory have a print that will be almost as permanent as straight pt/pd prints. Some of my bleaching tests seem to confirm that this is indeed the case.

    I think most people would agree that all silver prints, be they salted paper, albumen, kallitypes or contemporary silver gelatin, should be toned for greatest permanence.

  5. #25

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    How would the testing be done to determine if in fact the silver had been replaced with platinum in toning process? If this is in fact occurring do you think would it be more perminant than something like selenium?

  6. #26

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    Quote Originally Posted by Annie
    How would the testing be done to determine if in fact the silver had been replaced with platinum in toning process? If this is in fact occurring do you think would it be more perminant than something like selenium?

    Annie,

    There was a long thread of this topic recently on the largeformt site. Go to http://www.largeformatphotography.in...p?topic=496894 and join the thread, the title of which does not suggest any relevancy to your question, about halfway through. There was also some further discussion of this issue on the alt-photo-process list. If you have further questions after reading all that materias let me know.

    Jorge may also have other comments to make at this time about the issue.

  7. #27

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    Interesting thread. In light of the findings mentioned there I will continue trying variations of Pt/Pd toning with silver prints. The archival aspect seems promising but I found the selenium toned print has a very different look from the Pd toned print I made and it did not just relate to the colour shift, there is greater contrast with Pd and more 'open' midtones.

    Just as an aside, when I was looking for silver substitution formulas for Pt I came across this interesting web site that relates to Photographic Enamelling...

    http://www.enamellers.nl/english/carpenter7.htm

    In this photographic process the silver must be replaced or there is a yellow staining of the final product.... As the beginning procedures are similar to many of the Alt Photo processes I found it interesting that they are also using the Cobalt Chloride process similar to what I had found elsewhere..

  8. #28

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    [quote="Annie"]The archival aspect seems promising but I found the selenium toned print has a very different look from the Pd toned print I made and it did not just relate to the colour shift, there is greater contrast with Pd and more 'open' midtones.

    Annie,

    In my earlier response I did not address the aesthetic aspects of color and the impact of the toner on image appearance. However, you make a very interesting observation about print values and I have the same impression from my work in kallitype. Toning with platinum and palladium seems to open up the midtones and gives a greater sense of luminosity to the print. Toning with selenium just kills the luminosoity.

  9. #29

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    WARNING! read the following post by sanking first, this post contains some errors... cheers, annie.

    OK just one more posting.......

    Here is a link that is interesting because it mentions that one of the toned prints in the study as revealed by the analysis was in fact 100% platinum.... (actually the entire article is interesting)

    http://aic.stanford.edu/jaic/article...02-002_10.html

    However, Nadeau discusses here.......

    http://palimpsest.stanford.edu/byfor...1993/0387.html

    that when any silver remains the photograph is actually more vulnerable.... So to have the best of all worlds I will be testing toning my silver photographs with a combination of Pt/Au..... I am anticipating an opening of the midtones with the Pt and the assured permanence of the Au.

  10. #30

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    [quote="Annie"]OK just one more posting.......

    Here is a link that is interesting because it mentions that one of the toned prints in the study as revealed by the analysis was in fact 100% platinum.... (actually the entire article is interesting)

    Annie,

    Thanks for the link. Very interesting article.

    However, my reading of the article is different from yours, at least if I am understanding what you wrote above. When the articles states, "In addition to the silver image, three of the images analyzed revealed the presence of gold only; four showed a combination of gold and platinum; one had platinum only." I took that to mean that all eight prints contained silver, of which three contained also gold, four contained also gold and platinum, and one also only platinum.

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