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  1. #11

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    Quote Originally Posted by unclemack View Post
    Hi, mirror's lower edge at an angle doesn't indicate a maladjustment of the stop but a problem with the hinge mechanism at the top of the mirror or a twisted mirror carrier frame. With the mirror up and the shutter open you may be able to see the cause of the problem in good light with a magnifier. Hold the shutter open with a locked cable release to avoid damaging it.
    Looking at the underside of the mirror through the lens mount and the gate it should be possible to tell if it's horizontal and central, or is skewed in any way.
    If the mirror carrier or hinge mechanism needs straightening remove the mirror first for safety.
    Sorry to repeat myself but don't do anything until you're certain you know the exact cause of the problem.
    Thanks.

    Looking into the chamber with a flash light and wiggling the MIRROR_UP knob, it is clear to me that the whole mirror assembly goes up and rests down crocked. Here's something else. As I said earlier, on right side, there is a mirror stop. Also, the right side has the mirror-up assembly. The whole thing depends on right side to move it up and down.

    On left, there is a lever attached to this to move the aperture-close lever on lens. (so that the aperture will close when I release the shutter) I can tell, if I hold this lever by my finger to rel eave the pressure on left side, the whole mirror goes up and down leveled. Looks to me, the design depends on this assembly to keep its shape - and it apparently didn't.

    I've taken this camera apart before and I know for certain, there is no internal linkage going from left to right. (I was careful not to disturb anything else)

    From this, I am thinking, over years of use and uneven mechanical stress has caused this mirror assembly to twist and possibly worn linkage or pivot point.

    Can you help me with few things?

    A lot of alignment procedure depends on lens going to infinity focus. On this lens, it's all the way to right until it stops. How do I know this is actually calibrated correctly? Can it drift? I know, some of modern lens doesn't do this mechanical stop anymore. My Nikon lens actually goes to infinity few degrees before it's mechanical stop. On Mamiya, it's one and the same.

    Another thing is... how do I obtain suitable material so that I can use it to check focus at the film plane?? I do not have spare focusing screen. Are there any commonly available material that's suitable?
    Develop, stop, fix.... wait.... where's my film?

  2. #12

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    Hi, I'm sorry but I find it impossible to believe that Mamiya's designers & engineers would produce a mirror pivot assembly completely reliant on a one-sided mount! Early failure would be pre-programmed into such a design.
    I admit I remember the Super less well than other Mamiyas but I feel sure you've missed something here.
    The left mirror box wall where you say there's no connection to the pivot assembly - there is no curved slot? No vestige of a broken or missing lever or pin?
    If the mechanism really is as you describe it - it makes as much sense as a single-seater see-saw.

  3. #13

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    There IS a curbed slot on both sides and there are pivot on both sides. There is also a brace under the mirror that reinforces the mirror assembly. The only problem is, the right side is connected to the mirror up knob. Left side is connected to the shutter assembly. The mirror assembly itself acts as a torque bar to move the whole thing up and down.

    Here's another thing. As I said earlier, the mirror assembly rests on a foot that is on the right side. I can easily twist this mirror assembly (gently) to make it straight. As I keep my thumb on the mirror UP knob and try to hold the mirror assembly in mid-air (sort of speak), I can visually see the mirror twist.

    Either way, I can't see how this mirror can rest on one foot and keep it perfectly leveled. Not when it twists this much.
    Develop, stop, fix.... wait.... where's my film?

  4. #14

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    There MAY be a hidden linkage somewhere. But the point that I'm trying to make is, I don't see how this thing can rest flat on one side support only. Right now, I'm hesitant to take this a part again. I've taken the cover off the right side to repair shorted flash sync socket. I have not messed with the other side.

    I'd be thankful if you can help me with my Qs on previous post.
    Develop, stop, fix.... wait.... where's my film?

  5. #15

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    "Not when it twists this much" is the clue I've been waiting for...
    Many cameras have the lower mirror stop on one side only. I'm looking at a 1000S right now that is the same. It isn't a problem if the upper mirror brackets and pivots are secure on both sides - this is where you need to focus your attention. If left and right upper brackets/pivots can move relative to each other the "tripod" of 2 upper mounts + 1 lower stop is compromised - the mirror carrier is of course the frame of this "tripod."
    The stop-down lever is just that - a simple lever - when the mirror lifts it also lifts the back of the lever and the front of the lever moves down to close the lens diaphragm. It should move easily with the lightest touch of a finger -the stop-down levers on all lenses should also move freely.
    Once you've made the two pivots/brackets and mirror carrier a rigid assembly once again you will still need to check & calibrate infinity focus.
    Good luck.

  6. #16

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    Don't mess with the mirror. The focusing screen gets adjusted to the film plane focusing. As someone stated, using a GG on the film plane see if the screen matches the GG?

    If it does.....

    Perhaps you need a diopter instead? Have you checked your eyes?
    Anyone can make a Digital print, but only a photographer can make a photograph.

  7. #17

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    My eyes are fine, thank you....

    With mirror UP, I confirmed that pivot points are fine. They are not lose. Twist that I was talking about is actually caused entirely in the frame that mirror mounts on. I was able to "gently" twist it and put it where they rest nearly parallel to the bottom of the cavity. Not having another unit for comparison is making this process difficult. I'm sure these are not "rock solid" as in can't twist it with any force.

    How is this mirror mounted on this frame? I see 2 tabs on left and 1 tab on right. I don't see any screws to remove these tabs. I can feel, the mirror is not rigidly mounted on the frame. Almost feels and looks as if it has a cushion of some kind between mirror and the frame.

    I made a very flimsy "ground glass" and see that image on prism and GG agree fairly closely but not exactly. At infinity, it's pretty darn close. At close range, it's not that close but still fairly close. I'm going to stop now until I can pickup better loupe and construct much better GG.

    I found else where there are 4 screws that moves the focus screen closer or further from the mirror. I don't know where these screws are and I am not about to start unscrewing indiscriminately. I know there are several black screws under the prism and on both side of the screen (from top of the camera body). 4 of which are almost at the corners of the screen. Are these the one?

    I realize, mirror stop adjustment will not only change the distance but will also change the angle which the mirror sits relative to the lens axis and the focus screen. The height adjustment of the screen will change the distance itself.

    Thanks everybody for help. I'm closer to either fixing or destroying this camera. Time will tell which...
    Develop, stop, fix.... wait.... where's my film?

  8. #18
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    Send it in for a cleaning and inspection.
    Everytime I find a film or paper that I like, they discontinue it. - Paul Strand - Aperture monograph on Strand

  9. #19

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    That twist in the mirror is intensional and belongs there. You could have cracked the mirror as so many before you have done and has made me lots of money in the past selling mirrors for $90 a pop, but you were very lucky. Your problem is not the mirror, it's the screen or a diopter that makes the adjsutments. If you don't need one then you certainly need the other.. or both in some cases.

    Yes your eyes are perfect n can see the pubics of a fly, but did it ever cross your mind the wrong diopter is in there from a past owner?... or perhaps the screen was changed n never re-adjusted?

    Leave the mirror alone.. for anyone else messing with a mirror in the future.

    OH be sure to tell the reapir guy you twisted the mirror so he can readjsut it back?






    .
    Anyone can make a Digital print, but only a photographer can make a photograph.

  10. #20

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    Paul, is it possible that the OP was careful rather than just lucky?
    He stated his firm intention to do the work himself whatever the result in his second post.
    Yes, it's irritating and frustrating when equipment is presented for estimate which has been further damaged by users' attempts at repair - but when customers bring these cameras in person do we shout at them? Pour scorn on their efforts?
    The OP should send his camera to you for repair - because you already know that only a simple adjustment is required and therefore your charge for the work will be - what? $50? Sounds like a good deal to me.
    Last edited by unclemack; 03-26-2010 at 06:23 AM. Click to view previous post history.

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