Safelight Filters

Discussion in 'Darkroom Equipment' started by david b, May 9, 2006.

  1. david b

    david b Member

    Messages:
    4,031
    Joined:
    Oct 20, 2003
    Location:
    None of your
    Shooter:
    Medium Format
    I have several of the old Kodak screw in safelights with various red filters on them.

    Two are 0C, one is 0A, and one is 6B.

    I will be using Ilford multicontrast paper.

    Will I have an issue using any of these lamps with a 15w bulb?
     
  2. Dave Miller

    Dave Miller Member

    Messages:
    3,894
    Joined:
    Dec 22, 2003
    Location:
    Middle Engla
    Shooter:
    Medium Format
    A safelight test would be a good way to find out.
     
  3. Lopaka

    Lopaka Member

    Messages:
    757
    Joined:
    Apr 1, 2006
    Location:
    Michigan
    Shooter:
    Multi Format
    The OC filter is for the Multigrade paper. The OA is for graded papers and not safe for MG. 6B is for X-ray material.

    The bulb size depends on the distance from the work area. Might be 15w, might be 7.5w. When doing initial set-up, I do a quick and dirty to see if its close. Determine the base flash to give the paper a medium gray with normal development. Pre-flash the paper, then lay some coins on it for 5 - 10 minutes and process normally. Examine carefully after fixed. Any hint of coin outline indicates safelight fogging. When you think you have it, Kodak outlines a more scientific version of the test that will provide more comfort.

    Safelight filters begin to lose their effectiveness with use and age so need to be tested periodically.

    Bob
     
  4. david b

    david b Member

    Messages:
    4,031
    Joined:
    Oct 20, 2003
    Location:
    None of your
    Shooter:
    Medium Format
    Thanks Bob. Much Appreciated.