enlarger vignetting / light fall-off

Discussion in 'Enlarging' started by polyglot, Jul 16, 2009.

  1. polyglot

    polyglot Member

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    Hi all,

    I'm using an LPL 7700 with condenser head and Rodagon 105/5.6 (old Zebra version) to print 6x7. I made a bunch of 8x10s last night and am finding that the prints are distinctly paler in the corners. I was running the lens at f/11 to f/16 so didn't expect vignetting at all, particularly at this low magnification (lots of bellows extension).

    Is this a known issue with this lens or is it perhaps an issue with evenness of negative illumination from the head? I can burn the corners down a bit, but would prefer to get a uniform print straight off if possible.

    Any suggestions/reasoning appreciated...
     
  2. Erik L

    Erik L Subscriber

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    I'm not familiar with the lpl 7700 but do you have the condensers in the correct position?
    erik
     
  3. polyglot

    polyglot Member

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    uh, maybe? How do I tell what the correct position is?
     
  4. John Koehrer

    John Koehrer Subscriber

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    Some enlargers have a diagram inside the filter drawer access plate.
     
  5. polyglot

    polyglot Member

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  6. polyglot

    polyglot Member

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    That was exactly it. Found instructions on the inside of the front door - have to remove the top condenser element and push the bulb closer to it. Light nice and uniform now.