Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,826   Posts: 1,582,005   Online: 851
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 17
  1. #1
    tbm
    tbm is offline
    tbm's Avatar
    Join Date
    Jun 2004
    Location
    Southern California
    Shooter
    35mm
    Posts
    365

    RH Designs StopClock Professional timer's split-grade mode

    When using the above enlarger timer in the split-grade mode, does one have to change one's enlarger's filter setting to 0 for channel 1 and to 5 for channel 2? I ask becase the instruction manual for mine is not explanatory enough about performing the split-grade mode.

    Terry

  2. #2
    kraker's Avatar
    Join Date
    Oct 2005
    Location
    The Netherlands, close to the Belgian border
    Shooter
    Multi Format
    Posts
    1,196
    Images
    13
    The timer does assume that channel 1 is the soft channel (grade 00, 0, 1, or a lot of Y for a dichroic head) and channel 2 the hard channel (grade 4, 5, or a lot of M for a dichroic head).

    Whether you use grade 00, 0 or 1 for the soft, or 130Y, or 170Y; grade 4 or 5 for the hard, or 130M, or 170M: it doesn't really matter; just choose something that works for you and use it consistently.

    shuttr.net
    -- A sinister little midget with a bucket and a mop / Where the blood goes down the drain --

  3. #3
    tbm
    tbm is offline
    tbm's Avatar
    Join Date
    Jun 2004
    Location
    Southern California
    Shooter
    35mm
    Posts
    365
    Kraker, I must ask again, in a slightly different way: If, on my dichroic enlarger, I have the filtering set to, say, grade 3, does the split-grade feature automatically override that and move into low grades (for highlights) for channel 1 and high grades (around 5) for shadows?

  4. #4
    Nicholas Lindan's Avatar
    Join Date
    Sep 2006
    Location
    Cleveland, Ohio USA
    Shooter
    Multi Format
    Posts
    2,381
    Images
    4
    What enlarger are you using with the timer? If it is standard dichroic - Omega or Beseler, say - then the settings on the head do not influence the timer and vice-versa. It is up to you to coordinate the head filtration and the timer channels.
    DARKROOM AUTOMATION
    f-Stop Timers - Enlarging Meters
    http://www.darkroomautomation.com/da-main.htm

  5. #5
    jeroldharter's Avatar
    Join Date
    Nov 2005
    Location
    Wisconsin
    Shooter
    4x5 Format
    Posts
    1,958
    Images
    1
    The purpose of the "splitgrade mode" is to tie the two channels together so that if you adjust one channel, the timer automatically adjusts the other channel to maintain the same contrast.

    For example, you have determined that Channel 1 is 15 seconds at grade 0 (say 200 units yellow) and Channel 2 is 25 seconds at Grade 5 (say 200 units magenta) is the appropriate exposure for your print and you have a series of burns programmed into each channel. Then you decide that you want to print the whole thing 1/6 stop darker. In the split grade mode, you just nudge up one of the channels base exposure by 1/6 stop and the timer adjusts all the other times to maintain the same overall contrast for the print.

    In the disconnected mode, the two channels are completely independent of one another so adjusting the exposure in the soft channel has no effect on the hard channel and vice versa. That is the mode I use. I might have the explanation a but wrong because I never use the split grade mode but I think I am on track.
    Jerold Harter MD

  6. #6
    OMU
    OMU is offline

    Join Date
    Oct 2007
    Location
    Norway
    Shooter
    Multi Format
    Posts
    744
    Images
    67
    Hi,
    When using the split grade mode you must change the filters as Jerold explained.

    The hard channel (channel 2) is not affecting the soft channel (channel 1)
    That means that you can fine tune your contrast by the exposing time in channel 2.

    When the contrast is decided by the time in channel 1 and 2, you can make your photo darker or lighter by changing the exposing in channel 1. Channel 1 is affecting the hard channel. The channel 2 will change and keep the contrast as you have decided.

    So you should decide the soft expose first, then the hard expose.
    (Sorry for my english)

  7. #7
    RH Designs's Avatar
    Join Date
    Apr 2003
    Location
    Yorkshire Dales, England
    Shooter
    Multi Format
    Posts
    657
    Images
    18
    The timer clearly has no knowledge of what filtration you're using. We designed the split grade mode to use ch.1 for the soft exposure and ch.2 for the hard; if used together with Ilford filters (grades 00 and 5 respectively) and a typical white-light source the notional "grade" indication on the timer will be approximately correct. Other filters, colour enlargers etc. will differ, sometimes substantially. However the basic premise will hold i.e. in split grade mode, adjusting ch.1 mostly affects the overall exposure whereas adjusting ch.2 mostly affects contrast.
    Regards,
    Richard.

    RH Designs - My Photography

  8. #8
    RH Designs's Avatar
    Join Date
    Apr 2003
    Location
    Yorkshire Dales, England
    Shooter
    Multi Format
    Posts
    657
    Images
    18
    Quote Originally Posted by tbm View Post
    I ask becase the instruction manual for mine is not explanatory enough about performing the split-grade mode.

    Terry
    Terry - what firmware version do you have? (Check by reading the display during power-up). If it is earlier than v8.5 then the split grade mode works slightly differently and adjusting either channel will affect overall exposure. However, the comments regarding filters are still valid, on a dichro head set max Y when using ch.1 and max M for ch.2.
    Regards,
    Richard.

    RH Designs - My Photography

  9. #9
    tbm
    tbm is offline
    tbm's Avatar
    Join Date
    Jun 2004
    Location
    Southern California
    Shooter
    35mm
    Posts
    365
    Richard: Aren't these two comments contradictory?

    "The timer clearly has no knowledge of what filtration you're using."
    "On a dichro head set max Y when using ch.1 and max M for ch.2."

  10. #10
    clay's Avatar
    Join Date
    Nov 2002
    Location
    Asheville, North Carolina
    Shooter
    Multi Format
    Posts
    1,124
    Images
    8
    Not contradictory at all. The second statement tells YOU what to do when using the timer. The timer and the head do not 'talk' to one another. It needs the mediation of your own brain to make the whole thing work.
    I just want to feel nostalgic like I used to.


    http://www.clayharmon.net - turnip extraordinaire

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