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  1. #1
    Kyle M.'s Avatar
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    Koni Omega film back issue.

    So heres the deal, I recently bought a near mint Koni Rapid Omega 200 with one 120 back. Thankfully the frame spacing is good, the issue is an entirely different conundrum. As I shoot and advance the film the backing paper slowly walks up the take up spool and out and around the flange. Strangely enough the images remain centered on the film, even though you can tell this starts happening early on in the roll by looking at the exposed roll of film. Now this wouldn't be a problem except that sometimes when I unload the camera one edge of the last one or two frames gets a little bit of fogging. It doesn't always happen but more often than not it does. Has anyone ever seen this problem with an Omega film back and if so is there a fix besides hunting down and buying another back, or unloading in complete darkness?
    Yashica-Mat 124 G

  2. #2
    APUGuser19's Avatar
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    This back has a pressure plate that withdraws to let off pressure during winding. Inspect the entire mechanism for freedom of play and to be sure the entire plate lets off pressure. You may find it withdraws pressure unevenly at top or bottom, causing film to "walk". Also, just because it spaces evenly does not mean the clutch is not in need of disassembly, clean and lube. If you do take the clutch apart, beware the screws are VERY tight, and prone to the screwdriver chewing up the phillips (or slotted) head, rendering them impossible to remove. My guess is there's nothing wrong with the back per se, but needs maintenance. The clutch is a typical needle bearing mechanism, and the needles are dry and caked.

  3. #3
    Kyle M.'s Avatar
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    I knew that the pressure plate withdrew when you advance the film, but I've never looked at it to see if it was withdrawing evenly. I'll have to check it out when I get home.
    Yashica-Mat 124 G

  4. #4
    Chazzy's Avatar
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    The back probably needs a CLA, and Greg Weber is the man to do it. His email address is gweber@webercamera.com.
    Charles Hohenstein

  5. #5

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    Good Afternoon, Kyle,

    Be sure that the take-up spool is firmly clicked into the correct position and that you have carefully fed the paper backing squarely into the take-up slot. Any small error at the beginning leads to greater misplacement as the film is advanced.

    It might be worth using a long-outdated roll of film as a test roll to run through the back while it's off the camera. Maybe you can spot the problem that way.

    Konical

  6. #6
    Kyle M.'s Avatar
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    I pulled the advance clutch apart, cleaned it, and re-lubed it, and while I now have silky smooth advance I still have the same issue. Of course I'm also having a hard time seeing where anything could be mis-aligned, and the pressure plate is releasing tension evenly. This is very strange indeed.
    Yashica-Mat 124 G

  7. #7
    MattKing's Avatar
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    Maybe the pressure plate is restoring tension unevenly.

    Is there anything sticky on the pressure plate?
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  8. #8
    Kyle M.'s Avatar
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    Quote Originally Posted by MattKing View Post
    Maybe the pressure plate is restoring tension unevenly.

    Is there anything sticky on the pressure plate?
    Nope nothing sticky, pressure plate is clean as can be, honestly this thing looks like it's never been used.

  9. #9
    MattKing's Avatar
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    Is the takeup spool moving more than it should?
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  10. #10
    Kyle M.'s Avatar
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    The take up spool doesn't have any play in it and the latch that holds it in place seems to have plenty of tension on it. If I run a roll through it with the back removed from the camera all is fine. As soon as I insert it into the camera body or the insert and run it through it starts acting up. Almost as if the two aren't lining up right, but I don't see anything that looks out of place.

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