Omega F w/colorhead

Discussion in 'Enlarging' started by Rlibersky, Jul 12, 2005.

  1. Rlibersky

    Rlibersky Subscriber

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    Does anyone use a Omega F with the color head. I'm trying to get a good base for VC paper. It seems I have to be in the magenta 130 yellow 25 cyan 0 range to get a normal contrast print. This is not true with the Omega D2 with Ilford filters.

    Do the internal filters fade? Or am I just needing to test for this specific enlarger? Would be nice not to have different ASA for the same film.

    Moderators remove thread if it becomes to controversial. :wink:
     
  2. Nick Zentena

    Nick Zentena Member

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    The VC book put out by the guy that did the Darkroom cookbook includes a section on testing to figure out what grades you're getting.

    Why not just use the M and leave out the Y? Unless you're looking for speed matching between grades you won't lose anything going with just one filter.
     
  3. Rlibersky

    Rlibersky Subscriber

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    I will give that a try this weekend.
     
  4. Bob Carnie

    Bob Carnie Subscriber

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    Get rid of the yellow as Nick recommends and go higher on the magenta.
    Also sometimes the dichroic filters do stick, take out the mixing box and turn on the enlarger, you will see the filters and how they operate, make sure the magenta is dialing in fully, I have had this problem in the past ,not sure how to fix it as I have 7 thumbs but there are tons of very good people on this site who could help you if this is indeed the problem
     
  5. Nick Zentena

    Nick Zentena Member

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    One thing. Difffusion enlargers are about 1/2 grade softer then condensor enlargers. If the negative was developed for condensor then you'd need a touch more contrast.
     
  6. JackRosa

    JackRosa Member

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    Omega F head w/VC paper

    I use an Omega F head. The dichroic filters do fade - this is especially true of the magenta filter. I would get rid of the yellow filtration first and try just magenta filtration. 130M seems to be quite a high value to get a normal contrats print (from a normal contrast negative). My value ois closer to 15M.

    Let me know if I can be of further help.
     
  7. Ed Sukach

    Ed Sukach Member

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    Will someone please check the Data Sheets for Ilford MultiGrade papers? They include dichroic filtration stating points for both single and dual color filtration for obtaining the different contrast grades. Starting points. I have calculated my own "double filtration" values , which differ significantly - and they work very well.
     
  8. Rlibersky

    Rlibersky Subscriber

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    Have you ever changed one of the filters? If so, How difficult is it?.
     
  9. JackRosa

    JackRosa Member

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    I personally have not. I have Focal Point (in FL) do it.
     
  10. Rlibersky

    Rlibersky Subscriber

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    I finally found a manual for this enlarger and was suprised to see the filter eq. they use. (see attachment). If this is correct then I maybe getting I am supposed to.

    Jack if you would like a copy of this PM me. I can easily make a PDF of it.

    I'm not fimiliar with Kodak filters, so I couldn't talk about them.

    Randy
     
    Last edited by a moderator: Feb 27, 2008
  11. Rlibersky

    Rlibersky Subscriber

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    Bump, I forgot the attachment.
     
  12. Ronald Moravec

    Ronald Moravec Member

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    Negs that print on my D2 on 2 paper require about 30 magenta on the Chromega D.

    Yellow is reducing contrast. Cyan is just reducing the light.