Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,302   Posts: 1,536,247   Online: 726
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 20
  1. #1

    Join Date
    Sep 2002
    Location
    Pikes Peak
    Posts
    205
    In the thead "Mystery image" it has been proposed that the cause of the strange pattern found on some negatives may have been caused by photo flo carried over from poorly washed developing reels. I have wondered about this as I sometimes don't wash off the reels. Is this a probable or even a possible problem?

    I have also read threads wherein someone presoaks with photoflo or one person who even adds a dash of photoflo to the developer to even out developer. It has also been said that the reason Ilford recommends not presoaking (which I do even with Ilford film) is that the backing or emulsion has a little wetting agent included that gets washed away by presoaking.

    So whats the consensus opinion?

  2. #2
    Les McLean's Avatar
    Join Date
    Oct 2002
    Location
    Northern England on the Scottish border
    Shooter
    Multi Format
    Posts
    1,610
    I'm fairly sure that Ilford do not recommend presoaking because some years ago a well known British photographer had problems with uneven development that was traced to presoaking.

  3. #3
    David A. Goldfarb's Avatar
    Join Date
    Sep 2002
    Location
    Honolulu, Hawai'i
    Shooter
    Large Format
    Posts
    17,236
    Images
    20
    I presoak 11x14" and 8x10" sheets to be processed in pyro developers and find I get more even results that way. I also presoak East European films that have a blue-green anti-halation layer, because the dye comes out better that way, and doesn't seem to come out at the fixing or washing stage, like the magenta T-max dye.

    I wouldn't use Photo-Flo in the presoak or developer, though I've heard of this practice.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com

  4. #4
    Ole
    Ole is offline
    Ole's Avatar
    Join Date
    Sep 2002
    Location
    Bergen, Norway
    Shooter
    Large Format
    Posts
    9,281
    Blog Entries
    1
    Images
    31
    I presoak everything EXCEPT sheet film for tray development. But that's because my darkroom is leaking light, and I have discovered that the anti-halation layer protects the emulsion from exposure until the development is well under way. I will no longer do Maco 820c "AURA" in trays...
    -- Ole Tjugen, Luddite Elitist
    Norway

  5. #5
    garryl's Avatar
    Join Date
    Jul 2003
    Location
    Fort Worth, TX
    Shooter
    35mm
    Posts
    542
    Images
    2
    The only time I've used a wetting agent, in a developer, is in printing. I was experimenting with the Winchester formula. It is very simular to Dektol, except for adding a wetting agent. I quickly learned that it had to be a Non-ionic wetting agent(e.g. Edwal LFN). Every time I added Photo-flo to Dektol, I would get a tar like substance floating on the surface. The formula prove no better than plain Dektol.

  6. #6
    Jorge Oliveira's Avatar
    Join Date
    Jun 2003
    Location
    Brazil
    Shooter
    35mm
    Posts
    614
    A long time ago I've added some Agfa wetiing agent (forgot the name) to developer.
    I cannot comment in the results, since there was no significant difference. Due to that, I stopped using it.

    Jorge O

  7. #7
    Aggie's Avatar
    Join Date
    Jan 2003
    Location
    So. Utah
    Shooter
    Multi Format
    Posts
    4,925
    Images
    6
    ..

  8. #8

    Join Date
    Sep 2002
    Location
    Boston, MA
    Shooter
    Multi Format
    Posts
    970
    Images
    3
    I am no chemist but I would think that if a wetting agent (detergent?) were added to the developer (from poorly washed reels), it might "bubble up" during agitation and cause some strange effects with the developer. Just a thought..BobF may be on to something here.

    I find the metal reels easier to wash than the plastic types.

  9. #9
    clay's Avatar
    Join Date
    Nov 2002
    Location
    Asheville, North Carolina
    Shooter
    Multi Format
    Posts
    1,118
    Images
    8
    I attended a Mark Citret workshop a while ago, and he makes it a practice to pre-soak all of his tray developed 4x5 film for 5 minutes in a weak photoflo solution before putting the sheets in the developer. He has excellent negatives (and prints!!) with no signs of problems. I did the same while in the workshop and did not have any uneven development problems. I'm guessing it all depends on your particular habits and local water conditions. Heck, I even hear that some people get good negs from PMK. If you can do that, then photo-flo should be a cake-walk!

    Clay

    P.S. Mark's url is www.mcitret.com He is an excellent photographer, teacher and all round nice guy.

  10. #10

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    I pre-soak all films, roll film and sheet, for five minutes at the temperature of the developer. Never used PhotoFlo but often add a pinch or two of sodium carbonate to open the gelatin a bit and speed up induction.

    Can't say I have never had any problems in develoing film, but never have had one that I could blame on pre-soaking.

    Sandy

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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