105mm lens on C700?

Discussion in 'Darkroom Equipment' started by Theo43, Oct 19, 2009.

  1. Theo43

    Theo43 Member

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    Hello all,
    Has anyone used a 105mm enlarging lens on an Omega C700 (or earlier equivalent model)? Since 90mm to 100mm is the recommended size range for 6x7 negatives, I am wondering if you can do 11x14 enlargements with 105mm. Also, how would you rate the the El Nikkor 105mm F/5.6 as compared to other lenses? Thanks in advance,
    Ted
     
  2. Anscojohn

    Anscojohn Subscriber

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    I think you might be stretching it a bit to get an 11x14 on a C700 chassis. I have a 105 5.6 Nikkor (old style--silver) and a
    Vivitar VHE 100 5.6 (Schneider rebranded) I cannot tell the difference; although I have never done an actual test. Both are excellent lenses--6 element and slow. The old lab rats told me that given an equal number of elements in a lens, a slower lens will be sharper.
     
  3. Theo43

    Theo43 Member

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    Thanks John, that's pretty much what I thought. I am getting together the various pieces of gear for a darkroom, and will pay no further attention to 105mm lenses on the infamous auction site.
    Ted
     
  4. Rick A

    Rick A Subscriber

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    I tried putting a 90mm from my ProLab onto one of my C-700s last night, and it would not focus properly. It works perfectly on the big machine, only after shifting the condensors. I think what you want to do might not work, unless maybe removing a condensor. I am going to try that later on today.

    Rick
     
  5. Theo43

    Theo43 Member

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    I have been under the impression that any lens of appropriate focal length will work with any enlarger assuming the correct (e.g. 39mm) mount.
    Ted
     
  6. Rick A

    Rick A Subscriber

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    I retried my 90mm with and without the condensors in place. I believe that it requires a conical lensboard to obtain the proper spacing because I ran out of bellows extension just as image began to focus. Also, largest image possible is 5x7(barely) with the longer focal length lens, as it acts as a telephoto with 35mm format. After rereading my owners manual, I got it to work properly. I even got my 105mm, 135mm, and 150mm lenses to focus on the C-700. Keep in mind, that you can use the shorter focal length lenses with larger format, acting as wide angle(if you dont try too big a neg. with too small a lens)and get a greater enlargment size with less head elevation. Its possible to get 20x24 using 50mm with 6x6 neg. without turning the head. well, have fun with your machine, and experiment. Thats the fun of having a darkroom.

    Rick
     
  7. xtolsniffer

    xtolsniffer Member

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    There are numerous threads on here on 80mm vs 105mm for enlarging 6x7. Some manufacturers says it's fine to use an 80mm, others you should use a 105mm. I use a Schneider 80mm on my LPL6700 for 6x7 because if I used a 105mm (and I have borrowed one to try), then I can't get up to the maximum of 12"x16" on the baseboard, which is the largest I print. There is a hint that I may get about 1/2 a stop drop off at the corners, but I always burn in the edges and corners a little anyway, but there's no effect of resolution loss that I can tell. I'd rather be able to print large and have to burn the corners a little than not be able to print to my maximum size at all.