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  1. #1
    PhotoPete's Avatar
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    Omega D2 question

    I am going to post my question here, before I go over to classic enlargers and ask Harry.
    I have an Omega D2 with the variable upper condenser, which I believe makes it a D2V. I recently fiddled with the bellows adjustment that controls the distance between the neg stage and the lensboard. This caused some vignetting when printing 4x5 with the 135 mm lens, which I have resolved by removing the upper condenser as you would with a 150 mm lens. My question is twofold:

    1. What the heck is the name of that adjustment and control (it even has a scale)?

    2. How do I dermine what value on the scale should be set to for any given situation? I suspect it is some combination of neg size, focal length and enlargement factor.

    Thanks in advance.

  2. #2
    Will S's Avatar
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    You are using a cone with the 135mm lens right? I forget the size, but I think it is 3" or so. There are shorter and longer cones for different focal lengths.

    Thanks,

    Will
    "I am an anarchist." - HCB
    "I wanna be anarchist." - JR

  3. #3
    Bob Carnie's Avatar
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    I call it the lens bellows adjuster.
    It has a different setting for each lens. totally to the top for 35mm and down to the bottom for 150mm.
    I am suprised that with a 135mm lens you need to remove the condensor from the upper position.
    Are you sure the problem is not wrong positioning of the negative in the carrier?

    question two

    35mm neg- condensor bottom position -lens bellows all the way to the top.
    6x6mm negative - condensor middle position - lens bellow mid point
    4x5 inch negative - condensor top position or out - lens bellow bottom point.

    Quote Originally Posted by PhotoPete
    I am going to post my question here, before I go over to classic enlargers and ask Harry.
    I have an Omega D2 with the variable upper condenser, which I believe makes it a D2V. I recently fiddled with the bellows adjustment that controls the distance between the neg stage and the lensboard. This caused some vignetting when printing 4x5 with the 135 mm lens, which I have resolved by removing the upper condenser as you would with a 150 mm lens. My question is twofold:

    1. What the heck is the name of that adjustment and control (it even has a scale)?

    2. How do I dermine what value on the scale should be set to for any given situation? I suspect it is some combination of neg size, focal length and enlargement factor.

    Thanks in advance.

  4. #4
    PhotoPete's Avatar
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    Quote Originally Posted by Bob Carnie
    I am suprised that with a 135mm lens you need to remove the condensor from the upper position.
    Are you sure the problem is not wrong positioning of the negative in the carrier?
    I never had a problem until I messed with the bellows position- previously, I could print just fine with the 135 and the condenser placed per the instructions. I moved the carrier and the neg all around, so I knew that it was not the source of the problem.

  5. #5
    Bob Carnie's Avatar
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    Here is what I would do

    Go to your normal set up , if you are still getting vignetting , move the bellows up and down and watch what happens on the easel , also move the rough focus knob up and down. The bellows should be somewhere in the middle position. If the bulb, negative, lens and easal are all in synch you should not be having any problem whatsoever.
    I move this bellows all the time and in fact it is in different positions all the time depending on how much I am focusing . there is a rough focus knob and a fine focus knob on most of my Omegas.
    It may also be that you have racked out the focus too much and when you position the bellows you are not in a good focus to bellows position for a 135mm lens.

    Wish I could help you more

  6. #6

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    Quote Originally Posted by PhotoPete
    I recently fiddled with the bellows adjustment that
    controls the distance between the neg stage and the
    lensboard. This caused some vignetting when printing
    4x5 with the 135 mm lens, ...
    Fiddled? A few years have passed since I last checked
    for condenser focal length. Of course once it's set it stays.
    IIRC, I removed the lens with board then measured the
    distance from the bottom surface of the bottom
    condenser to the focal point of the light bulb.
    That's what the condensers do, focus the
    light from the bulb.

    As I recall the lens at it's likely greatest extension is to fall
    within the focal length of the condensers. If you need
    more light for small negatives the light from the bulb
    is made more condensed; focused more near the
    negative stage.

    There's nothing to making the condenser measurements.
    Check for other combinations while you're at it. Dan

  7. #7

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    Here's what my D2V instruction book says:

    162mm-150mm lens: Remove the variable condenser (which they also refer to as the "auxiliary lens) entirely

    135mm lens: The variable condenser goes in Position 1 (top position)

    105mm-90mm lens: The variable condenser goes in Position 2 (middle position)

    80mm-50mm lens: The variable condenser goes in Position 3 (bottom position)

  8. #8
    Will S's Avatar
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    I guess my D2V does not have one of these "lens bellow adjustment" thingies, which is why I need cones. Is it possible to buy these? Of course, I have all of the cones already...

    Thanks,

    Will
    "I am an anarchist." - HCB
    "I wanna be anarchist." - JR

  9. #9
    PhotoPete's Avatar
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    After closer inspection of the Omega pictures on www.khbphotografix.com, I don't have a D-2 after all. It's a D-5, without the XL column.

  10. #10
    Photo Engineer's Avatar
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    The cone for the D2V / 135mm lens is 4.5 " measured from mount to mount.

    PE

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