Omega bulb questions

Discussion in 'Darkroom Developing and Printing' started by Lew, Jan 25, 2006.

  1. Lew

    Lew Guest

    Ok, I've begun the process of adapting an omega head to my Zone vi. I'm
    going over the specs on the kbh web site, and I see 211 screw base lamps
    listed for all models. The used heads I've accumulated both have 111
    bayonette bases. Is this of any concern to me?
    -Lew
     
    Lew, Jan 25, 2006
    #1
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  2. Which model Omega do you have? The PH211 or 212 medium
    screw base bulbs are standard in the 4x5 D2 and D-II
    versions and some others. The bayonet bulbs are used in some
    smaller format models and in some Omega color heads.
    Whichever head you decide to use make sure that new bulbs
    are still available for it.
     
    Richard Knoppow, Jan 25, 2006
    #2
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  3. The B22 medium format head uses a 111A bayonet base lamp; the D series
    4x5 condenser heads use a 211 (75W) or 212 (150W) bulb that has the
    common light bulb screw base. I use 212s. The dichro heads use quartz
    halogen bulbs. You might want to check out the manuals on John's
    website: http://www.puresilver.org/docs/equipment/enlargers/enlargers.html
     
    Michael Gudzinowicz, Jan 25, 2006
    #3
  4. Lew

    Lew Guest

    Ok, looks like I've got 2 B series heads. One has "Type B" on the plate
    opposite the bulb socket, the other doesn't id the model. I'm mainly
    interested in seeing how my underdeveloped 35's will look under a condenser,
    and I should be able to mount it on the z6 anyway.
    -Lew
     
    Lew, Jan 26, 2006
    #4
  5. A condenser head will not fix underexposures. The sort
    of partially diffusing condenser found on these enlargers
    produces about one paper grade more contast than one would
    get on a diffusion enlarger. I think I get less than that on
    my Omega D2v.
    Increasing the contrast will separte details in the
    shadows somewhat because they are recorded at lower contrast
    than more fully exposed parts of the image, but the entire
    image is being printed so that part which got full exposure
    will be overly contrasty. At some point of underexposure
    there will simply not be anything in the shadows to recover
    although its surprizing how thin a negative can be and still
    print.
    Increasing contrast in printing will also exagerate any
    blemishes or dirt on the negative. When high contrast paper
    is used it will also exagerate any uneveness in the light
    source. All things to watch out for.
    One method of getting reasonably good prints is to make
    masks and print different parts of the image with different
    variable contrast filters (on VC paper of course). This is a
    lot of work but can give you results not possible in any
    other way.
    If you already have a good tungsten diffusion head or a
    color head you can probably get enough contrast by using the
    highest contrast filters. For a color head, the use of an
    actual VC filter will often give you a higher contrast than
    the built in filters.
    Cold light heads will generally compress the contrast
    range at both ends although its worth a try if you already
    have one.
    I have managed to get prints of what I call salvage
    quality from negatives which looked nearly clear with a
    little care.
     
    Richard Knoppow, Jan 26, 2006
    #5
  6. Lew

    Lew Guest

    I'm primarily concerned with a backlog of negs that have been
    underdeveloped, not underexposed. Thanks.
     
    Lew, Jan 26, 2006
    #6
  7. Lew

    John Guest

    And development ?

    ==
    John - Photographer & Webmaster
    www.puresilver.org - www.xs750.net
     
    John, Jan 27, 2006
    #7
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