Focusing by means of split-image wedge

Discussion in 'Darkroom Equipment' started by AgX, May 28, 2009.

  1. AgX

    AgX Member

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    To my knowledge the Fujimoto G-70 (6x7cm) enlarger is the only one that employs a split-image wedge by wich means a line is projected onto the baseboard next to the image area to assist focusing.

    Has anyone experience with this kind of focusing for enlarging?
     
  2. BetterSense

    BetterSense Member

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    How does this work? Where is the split-wedge placed? Sorry I can't help, but that sounds like a great idea.
     
  3. ic-racer

    ic-racer Member

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    Cool. Where is the little prism.
     
  4. Adrian Twiss

    Adrian Twiss Member

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    I can't speak for the Fujimoto but the Opemus range of enlargers also had split image focussing. It was built into the negative carrier. I found that it worked very well. However, I always double checked focus with a grain magnifier.
     
  5. Anon Ymous

    Anon Ymous Member

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    Hello Adrian

    I assume you were not using a glassless carrier. I tried the split image focusing, but didn't work. The manual says it can only be done with glass carriers.
     
  6. Blacknoise

    Blacknoise Member

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    I think my Durst M301 has something like this, it projects green and red with a weird filter. Dont know how it works to be honest. I just use my eyes, and everything looks nice and sharp on the prints. But I think I'll invest in a grain magnifier when payday comes round...
     
  7. AgX

    AgX Member

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    This is something similar: A red and cyan mark are projected onto the easel. If the negative plane is out of focus, the two marks will overlap, forming a white center and coloured edges. If in focus, they form a true white mark.
    (At least that is what I understand from the Durst manual.)