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05-14-2012, 05:55 AM   #1
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Mirror flops and DOF preview problems?

My k-r recently had to go back for repair - it developed the uncontrollable mirror flop problem (mirror flop whenever any button was touched).
It has been repaired (under warranty) and that problem has gone. But there is still a mirror flop problem though much less frequent.
(a) With some lenses, using DOF preview involves a "double flop" - where the mirror goes up and down quickly, and the aperture opens/closes quickly. This never happens with the same lenses on my old K100D.
(b) With some lenses (again, no problem on the K100) - if used in "A" mode, and opened up to F2.8, the mirror does an extra "flop" a couple of seconds after the shutter. Weirdly, it only does this in some orientations (i.e., won't do it if the camera is held upside down).

Is this an electronic problem, or more likely to be a mechanical glitch in the aperture lever (e.g, for all I know it might be "slipping", but not on the K100D)
I can still send it back for another look but if there is a simple fix, would save me being without the k-r for a few weeks.



05-14-2012, 08:04 AM   #2
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Join Date: Jul 2010
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My experience with my Kx and a couple of lenses was the lens aperture lever , if it does not allow the camera
lever to fully return to it's stop position it can cause what sounds like a double mirror flap at times.
Remember the camera does not close the aperture it holds it in the open position and lets the lens spring close it, so
when in the open position there has to be a small amount of play between the lens and camera levers so the camera
seat the aperture drive without forcing it and not allowing it to shut down.
It is probably not reporting to the system that the lever has returned so it keeps trying. Could possibly end up damaging the mechanism causing
the permanent problem.
05-14-2012, 08:15 AM   #3
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Join Date: Mar 2012
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Original Poster
Thanks - does anyone know if the k-r and the k100 have different aperture control mechanisms (if the K100 is stronger, or, built differently, that might explain it). Also - any way to test that this is where the problem is, without sending it back for repair?
05-15-2012, 02:46 PM   #4
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Join Date: Jul 2011
Location: Tyneside
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What lenses are you using when the mirror flop happens ?
I had the mirror flop with my K-r when i tried to use a couple of old manual lenses ,I seen a post on here where someone said they was
having the same problem and using the camera with the AA battery holder cured it , so I bought a cheap copy of the battery holder and
I can now use the two manual lenses without the mirror flop.


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