Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,928   Posts: 1,556,838   Online: 806
      
Page 2 of 6 FirstFirst 123456 LastLast
Results 11 to 20 of 59
  1. #11
    MattKing's Avatar
    Join Date
    Apr 2005
    Location
    Delta, British Columbia, Canada
    Shooter
    Multi Format
    Posts
    12,589
    Images
    60
    Quote Originally Posted by Ian Grant View Post
    A Potassium Ferricyanide/Potassium Bromide bleach is a re halogenating bleach, more usually used for toners.

    For artwork and complex reduction it's sometimes more useful than Farmers.

    Using Potassium Ferricyanide on it's own followed by fixing is quite different in effect to the action of Farmers Reducer.

    If you add ferricyanide to commercial fixer it's an agressive bleach particulary if the fixer is ammonium thiosulphate based. However Farmers Reducer uses plain Sodium Thiosulphate and the action is far more gentle and it's useful for lightening shadow details and much slower working.

    Ian
    Ian (and others):

    Would the bleach included with Kodak's Sepia Toner or Sepia Toner II packages be appropriate for this purpose, and if so, at what dilution?

    Thanks
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  2. #12
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,330
    Images
    148
    Yes, it's a Ferricyanide/bromide bleach so ideal

    Different papers and even paper/developer combinations have an effect on how fast a bleach works. You need 1/10th or less the normal strength needed for full bleaching for toning, 1/100th may be sufficient.

    Ian

  3. #13
    MattKing's Avatar
    Join Date
    Apr 2005
    Location
    Delta, British Columbia, Canada
    Shooter
    Multi Format
    Posts
    12,589
    Images
    60
    Thank you.

    I foresee some experimentation in my future.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  4. #14
    RalphLambrecht's Avatar
    Join Date
    Sep 2003
    Location
    Central florida,USA
    Shooter
    Multi Format
    Posts
    6,622
    Images
    1
    Quote Originally Posted by Ian Grant View Post
    ... Using Potassium Ferricyanide on it's own followed by fixing is quite different in effect to the action of Farmers Reducer. ...
    I have not experienced any difference, and I don't see why this would be either.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  5. #15

    Join Date
    Jan 2007
    Shooter
    Medium Format
    Posts
    834
    Images
    131
    I don't see why there would be any difference, either. Except one is is irreversible. I probably wouldn't want to try this on prints that are difficult to replicate.

  6. #16
    Ian Grant's Avatar
    Join Date
    Aug 2004
    Location
    West Midlands, UK, and Turkey
    Shooter
    Multi Format
    Posts
    16,330
    Images
    148
    Quote Originally Posted by RalphLambrecht View Post
    I have not experienced any difference, and I don't see why this would be either.
    There should be because the sodium thiosulphate and ferricyanide work together, but it depends what you're trying to retouch.

    If you're just using a bleach on the highlights then the differences are not as significant, Farmers reducer exhausts quite quickly in use which helps the control-ability when retouching. The prescence of the thiosulphate help particularly when reducing shadow areas.

    I seem to remember in a previous thread you used ferricyanide & rapid fixer as a reducer, and Ron Mowrey (PE) pointing out the aggressive nature of the combination.

    Perhaps a simpler explanation is that Ferricyanide on it's own attacks the smaller grains first, that's why it's used with or without bromide for split toning, but with Thiosulphate added Farmers Reducers attacks the larger "black" grains as well at the same time.

    If you put a print in a ferricyanide/bromide bleach some blacks don't bleach until the last moment, which is what's used in split toning, you control the time to pull from the bleach. Put a print in fresh Farmer's and leave it and it'll lighten more progressively across all the tones - very different.

    Farmer's cannot contain commercial fixer only plain sodium thiosulphate anything else is very different in behaviour.

    Ian
    Last edited by Ian Grant; 10-01-2010 at 01:21 PM. Click to view previous post history. Reason: add

  7. #17

    Join Date
    Mar 2008
    Shooter
    4x5 Format
    Posts
    82
    Images
    2
    Barry Thornton's Edge of Darkness describes a process whereby you selenium tone first, then wash, then apply the Potassium Ferricyanice/Potassium Bromide bleach (and 3g/liter is still kind of strong, in my experience); then fix again, but you can redevelop and do it all over again as long as you wait to re-fix until you're satisfied. The selenium holds back the darker areas, and the highlights get a fuller bleaching.

    As other have noted, you get some changes in color (more with some papers than others); and every re-bleach, re-fix, re-develop or re-whatever that you do seems to take its toll on the print, until after several rounds you end up with something that just looks really...tired.

  8. #18
    Bob Carnie's Avatar
    Join Date
    Apr 2004
    Location
    Toronto-Ontario
    Shooter
    Med. Format RF
    Posts
    4,676
    Images
    14
    Ian : this sounds pretty logical, what do you think. If I bleach and refix after selenium, then move to my sepia tone and gold for the look, ??
    Quote Originally Posted by An Le-qun View Post
    Barry Thornton's Edge of Darkness describes a process whereby you selenium tone first, then wash, then apply the Potassium Ferricyanice/Potassium Bromide bleach (and 3g/liter is still kind of strong, in my experience); then fix again, but you can redevelop and do it all over again as long as you wait to re-fix until you're satisfied. The selenium holds back the darker areas, and the highlights get a fuller bleaching.

    As other have noted, you get some changes in color (more with some papers than others); and every re-bleach, re-fix, re-develop or re-whatever that you do seems to take its toll on the print, until after several rounds you end up with something that just looks really...tired.

  9. #19

    Join Date
    Feb 2008
    Location
    Greece
    Shooter
    35mm
    Posts
    1,322
    Bob, it's not an easy task to bleach and refix, then do any toning. If you bleach to completion and refix, everything is gone and there's nothing to tone.

  10. #20
    Bob Carnie's Avatar
    Join Date
    Apr 2004
    Location
    Toronto-Ontario
    Shooter
    Med. Format RF
    Posts
    4,676
    Images
    14
    Anon
    I am printing solarizations, the highlights are a mid grey, all I want to do is lift them up to a brighter level, I am not bleaching to completion.
    I have found that all my tests in the past lack a POP that I think brighter highlight region could give.
    I cannot get it *the pop*without some way of making them brighter.

    Bob
    Quote Originally Posted by Anon Ymous View Post
    Bob, it's not an easy task to bleach and refix, then do any toning. If you bleach to completion and refix, everything is gone and there's nothing to tone.

Page 2 of 6 FirstFirst 123456 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin