Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 75,714   Posts: 1,669,884   Online: 1013
      
Page 2 of 2 FirstFirst 12
Results 11 to 12 of 12
  1. #11
    Donald Qualls's Avatar
    Join Date
    Jan 2005
    Location
    North Carolina, USA (transplanted from Seattle)
    Shooter
    Multi Format
    Posts
    1,845
    Quote Originally Posted by Gerald Koch
    When Diafine (and Acufine) first came out film manufacturers were including a large safety factor in their film speeds. The speed ratings quoted for these two developers took advantage of this and it looked like you were getting a large speed increase. Now there is little or no safety factor in the ISO speed ratings. If you use the suggested ratings for these developers expect very thin negatives. In reality you can expect only a modest speed increase of about 1 stop with Phenidone based developers whether they be two bath or conventional. You can get more speed with low contrast subjects but there is no magic here either.
    I have to disagree here. I've got several rolls of pretty normal looking negatives shot on Tri-X at EI 1600, in lighting ranging from flat dawn light to direct sun (f/16 at 1/1000, about 2/3 stop "overexposed" for EI 1600). I don't find them flat or thin and they print as well as any 35 mm B&W I've got.

    Unfortunately, since the meter died in my Spotmatic, I haven't used Diafine much because the only other camera I have that can meter above EI 400 has only DX to set film speed, which is a pain to fool for EI 1600 (EI 3200 is much easier, and obtainable with Diafine using a little trickery, but does give rather empty shadows).
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  2. #12

    Join Date
    Dec 2004
    Shooter
    Multi Format
    Posts
    1,670
    Quote Originally Posted by Donald Qualls
    I have to disagree here. I've got several rolls of pretty normal looking negatives shot on Tri-X at EI 1600, in lighting ranging from flat dawn light to direct sun (f/16 at 1/1000, about 2/3 stop "overexposed" for EI 1600). I don't find them flat or thin and they print as well as any 35 mm B&W I've got.
    I'm glad that your satisfied with your negatives, that's really all that counts. However, you have established is an effective film speed based on your processing methods. Someone else may get entirely different results. Without a sensitometer it would be hard to determine the actual film speed. What is importasnt is the shadow speed. I stand by my criticism that the makers of Acufine/Diafine inflate their speed ratings.

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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