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  1. #1

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    Omega D2V Uneven Illumination Problem

    Good Evening All,

    I'm having some problems getting even illumination from my Omega D2V enlarger. I noticed that the center of my 8x8" prints are dark in the middle with lighter edges. At first I thought it was my camera, then I switched to the 23C and problem is gone.

    I'm using a 80mm Nikkor lens enlarging 6x6. I have the adjustable condenser lens set to the LOWEST position. Also the lens board is flat, no cone. The condensers are clean. I exposed a sheet without a negative and you can clearly see the dense areas, not even in the center of the print as well as a hot spot in the print. Any idears on whats up with this crazy enlarger?

    Thanks,

    Marco S.

  2. #2

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    Are the fixed condensers installed properly (flat surfaces facing outwards)?

  3. #3

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    Yes, they sure are. If I move the top condenser up all the way will this soften the light enough so that the bulb is more or less out of focus?

  4. #4

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    Quote Originally Posted by Marco S. View Post
    If I move the top condenser up all the way
    will this soften the light enough so that the
    bulb is more or less out of focus?
    Try this. With no or the 4x5 negative carrier in place
    crank up the enlarger, then note the focal distance of
    the bulb on a sheet of paper. The greater that distance
    the greater the covering power of the condensers. Over
    coverage is OK but under equals dense centers.

    The flat surfaces are to face the bulb and negative.
    You are working with two condensers? The two in
    some combination may make it to 35mm. Dan

  5. #5

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    Dan,

    The condensers are facing each other, both curved edges towards each and flat sides facing bulb and negative carriers. There is a third condenser that you move to adjust for the lens size, ie 50, 80, and so on.

    I did some more investigating and there seems to be a bright spot near the top of the frosted part of the bulb, facing the negative stage when it's lit. Although very small, 1-2 mm in diameter when looking at the bulb, it's very noticable. I'm thinking that the condensers are magnifying this imperfection in the frosting and therefore showing up as a bright or hot spot on the prints.

    Do you think I could put a thin piece of diffusing material, like a Rosco gel and that would help soften and blend the light evenly? (Or just buy a new bulb, seeing as this one is probably 20 years old or older).

  6. #6

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    Quote Originally Posted by Marco S. View Post
    Dan, There is a third condenser that you move to
    adjust for the lens size, ie 50, 80, and so on.

    I did some more investigating and there seems to
    be a bright spot near the top of the frosted part of
    the bulb, facing the negative stage when it's lit.

    Do you think I could put a thin piece of diffusing material,
    like a Rosco gel and that would help soften and blend the
    light evenly? (Or just buy a new bulb, seeing as this one
    is probably 20 years old or older).
    Any diffuser would need to be used close to that bulb. That
    bulb may be all of your problem. A diffuser can't be any more
    than a partial correction. I've an Omega B8, a junior D2, for
    which a new bulb arrived from Freestyle.

    What does the V designate? I know of DII and D2. Dan

  7. #7

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    Quote Originally Posted by dancqu View Post
    Any diffuser would need to be used close to that bulb. That
    bulb may be all of your problem. A diffuser can't be any more
    than a partial correction. I've an Omega B8, a junior D2, for
    which a new bulb arrived from Freestyle.

    What does the V designate? I know of DII and D2. Dan
    hi dan

    the v is for auto focus i think.
    i have a government-contract d3v and
    there are rails that the cone/focusing bellows
    rides on. the rail has shape to it ( different depending on
    the fl lens used (like the cones) ) , so the bellows opens/closes
    depending on the distance from the easle and the original focus.

    i have heard people mention putting diffusion material
    ( milk glass /diffusion glass from a local glass company )
    and putting it either above or below the aux. condensor that goes
    above the big condensors.

    good luck!

    john

    ps. harry taylor ( the omega-man at http://www.classic-enlargers.com ) can probably help you fix your problem. he knows these enlargers backwards and forwards.
    silver magnets, trickle tanks sold
    artwork often times sold for charity
    PM me for details

  8. #8
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    Hi, John.

    I hate to be the fussy nit-picker offering a correction of trivia (but....)(someone has to do it).

    The "V" designation is for those Omegas with a variable condenser, the small uppermost one that is raised or lowered according to the negative size/format.

    I second your vote of confidence for Harry Taylor; he's the guru and he's a genuinely nice guy.

    Cheers
    Michael Robert Taylor
    Ottawa

    I wish I'D said that.... Bartlett

    http://www.apug.org/gallery1/browsei...imageuser=7358

  9. #9

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    Thanks friends. I will change out the bulb and let you know if that was the problem. Yes, V in D2V is for the variable condenser in the lamphouse.

    Regards,
    Marco



 

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