Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,755   Posts: 1,515,991   Online: 884
      
Page 1 of 3 123 LastLast
Results 1 to 10 of 27
  1. #1

    Join Date
    Aug 2004
    Location
    Eastern Maine (Washington County)
    Shooter
    Multi Format
    Posts
    92
    Images
    5

    Blue fomapan 100 negs

    In my recent round of film testing, I just processed my first roll of fomapan 100. The negs look very nice, and quite sharp in pyrocat, but the roll has a very pronounced blue color, like the sensatising dyes didn't get washed off entirely. It looks like a roll of t-max that hadn't gotten fixed and washed properly, but instead of a magenta cast, it's blue. Has anyone else seen this, or have any ideas on what might be the cause? My process was pre-wet for 5 min. with nearly continuous agitation, develop in pyrocat 1:1:100, water rinse for 45 sec, fix for 5 min in kodak powder fixer, 2 min. in kodak HCA, 15 min. wash (in a roll film washer), photo flow, hung to dry. I tested the fix, and it seemed good, it cleared a piece of tri-x in about 60 sec., and the roll of jandc 100 I had in the same tank at the time cleared fine.

    Peter

  2. #2
    rjr
    rjr is offline
    rjr's Avatar
    Join Date
    Aug 2004
    Location
    Mosel, SW Germany
    Shooter
    Medium Format
    Posts
    409
    Images
    4
    Peter,

    Quote Originally Posted by pwitkop
    In my recent round of film testing, I just processed my first roll of fomapan 100. The negs look very nice, and quite sharp in pyrocat, but the roll has a very pronounced blue color, like the sensatising dyes didn't get washed off entirely.
    Peter
    That´s normal. I´d describe it as a blue/greenish cast. The color cast is in the layer, there is no way to wash it out.

    Some people dispise the color, but the film will print fine nevertheless. ;-)
    Tschüss,
    Roman

  3. #3

    Join Date
    Aug 2004
    Location
    Eastern Maine (Washington County)
    Shooter
    Multi Format
    Posts
    92
    Images
    5
    The test negative I printed looked fine, as long as it's normal, I cerntainly don't mind. I'd just never seen it before so I figured I must have done something wrong

  4. #4
    David A. Goldfarb's Avatar
    Join Date
    Sep 2002
    Location
    Honolulu, Hawai'i
    Shooter
    Large Format
    Posts
    17,140
    Images
    20
    Efke, Foma, and Forte films all have this dye. It will come out with a 2-minute presoak. Unlike the magenta dye in Kodak films, the blue-green dye doesn't seem to come out so easily in the fix or wash.
    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

  5. #5
    rjr
    rjr is offline
    rjr's Avatar
    Join Date
    Aug 2004
    Location
    Mosel, SW Germany
    Shooter
    Medium Format
    Posts
    409
    Images
    4
    David,

    Quote Originally Posted by David A. Goldfarb
    Efke, Foma, and Forte films all have this dye.
    No. The three companies have very different approaches towards base, AHU and sensitising of their emulsions.

    Efke uses a clear polyester base for the rollfilm and they use the same dies Kodak, Ilford and others use plus a blue AHU laquer (which comes off in presoak or developing). Sometimes a pink cast is left after fixing and washing and this will clear with a soda bath or some hours in the sun (I hang the cut film in the sheet on the inside of a window).

    IIRC Forte uses a plain triacetate base with greyish tone. Haven´t used it in a while.

    Foma uses a polyester base, too. But this one has a tint that will not fade or wash out.

    Let me cite the spec sheet for Fomapan 100 (from www.foma.cz):

    "Base

    The following bases are used for manufacturing the particular sorts of the film:
    120 rollfilm - a bluish polyester base 0,1 mm thick, furnished with a matted
    backing which will decolourize during processing. The backing has anti-halation and anti-curling properties and prevents the incidence of Newton rings during
    enlarging.

    35 mm film - a gray or gray-blue cellulose triacetate base 0,135 mm thick,"

    I don´t know which brand of polyester base they are using - many western companies use DuPont´s Melinex which is totally clear by itself.
    Tschüss,
    Roman

  6. #6
    David A. Goldfarb's Avatar
    Join Date
    Sep 2002
    Location
    Honolulu, Hawai'i
    Shooter
    Large Format
    Posts
    17,140
    Images
    20
    Thanks for the more detailed info, Roman. Whatever the dye is, I've been using Efke 100, Fomapan T200, and Classic/Forte 400, and a presoak works with all of them.
    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

  7. #7

    Join Date
    Aug 2004
    Location
    Eastern Maine (Washington County)
    Shooter
    Multi Format
    Posts
    92
    Images
    5
    I wonder what the reason for the blue base is in roll film. The 35mm uses a gray/gray blue base, and the sheet film a clear base, I wonder what problem it solves that isn't existant in the other formats. Whatever the reason, the colored negs are kinda neat to have around in the darkroom, adds a splash of color

    On a side note, reading the pdf on the foma web site, it mentions cm sheet film sizes. I know 9x12 is at least aproximately the same size as 4x5, but does anyone know if it is exactly the same, or close enough that it would fit in standard 4x5 film holders? The results from foma pro 100 in 120 seem very promising so far, I'd like to possibly try it in large format as well.

    Peter

  8. #8
    Les McLean's Avatar
    Join Date
    Oct 2002
    Location
    Northern England on the Scottish border
    Shooter
    Multi Format
    Posts
    1,610
    Quote Originally Posted by David A. Goldfarb
    Thanks for the more detailed info, Roman. Whatever the dye is, I've been using Efke 100, Fomapan T200, and Classic/Forte 400, and a presoak works with all of them.

    David, have you had any problems with uneven development, best seen in areas of plain mid grey such as a sky, when you have presoaked a this film, surely the blue dye is in there for a purpose. I ask because some years ago Fay Godwin had serious uneven development when presoaking FP4 and the problem was identified as presoak. When she stopped this practice the uneven development disappeared.
    "Digital circuits are made from analogue parts"
    Fourtune Cookie-Brooklyn May 2006

    Website: www.lesmcleanphotography.com

  9. #9
    Helen B's Avatar
    Join Date
    Jul 2004
    Location
    Hell's Kitchen, New York, USA
    Shooter
    Multi Format
    Posts
    1,557
    Images
    27
    Maco Cube 400c also has a blue base that survives processing - it behaves quite differently from a dye in a coated layer.

    David, I think that Fomapan 200 only has a blue dyed-in-the-mass base with the 120: the 35 mm is grey and the sheet film is clear, isn't it? Were you referring to 120 or sheet film?

    Best,
    Helen

  10. #10

    Join Date
    Jul 2004
    Shooter
    Multi Format
    Posts
    3,042
    Quote Originally Posted by rjr
    "Sometimes a pink cast is left after fixing and washing and this will clear with a soda bath or some hours in the sun (I hang the cut film in the sheet on the inside of a window)."
    I was always told that negatives should be kept away from sunlight. Is this no longer the case? If not then I don't need to spend so much time in darkend rooms.

Page 1 of 3 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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