Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,285   Posts: 1,535,271   Online: 878
      
Page 2 of 2 FirstFirst 12
Results 11 to 14 of 14
  1. #11
    Athiril's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne, Vic, Australia
    Shooter
    Medium Format
    Posts
    2,498
    Images
    28
    Quote Originally Posted by Photo Engineer View Post
    It is very very difficult with any color film to increase contrast without messing the color quality. You get crossover. Even the Sulfite trick causes some crossover. I can suggest some methods such as adding more CD4 and adjusting the pH back to normal, or just raising the pH with base. But, sadly, these do cause problems.

    The best way to do what you want is a simple push, and even that is mediocre IMHO. Remember, I used to coat these films so I know what the problems are in every detail.

    Hey, if you can get some Gold, or the consumer equivalent, that has higher contrast than Portra. It pushes no better but starts higher by about 0.01 in contrast (or thereabouts). It is made for the consumer market with higher contrast to give the pix a higher snap and to compensate for the flare of non-professional systems.

    Try it, you might like it.

    PE
    Benzyl alcohol and increased potassium iodide?

  2. #12
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    22,972
    Images
    65
    Tried BZA to no avail with the new couplers. KI does nothing at all to the contrast AFAIK.

    PE

  3. #13
    Athiril's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne, Vic, Australia
    Shooter
    Medium Format
    Posts
    2,498
    Images
    28
    Oh, that's a real shame! It's relatively inexpensive and not difficult to get. The other one I've been reading about is polyethylene glycol, and possibly benzalkonium chloride which have other common uses.

  4. #14
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    22,972
    Images
    65
    Well Dan, give them all a try if you can get them easily.

    Best wishes.

    PE

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