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12-02-2012, 06:40 PM   #1
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Stuck focus SMC F 28 f2.8

Well, for what ever reason when I pulled my trusted SMC F 28 2.8 lens from my bag after a trip it failed to focus when I put it on my camera. The focus ring turns freely but there is no focusing going on. Does anyone have any tips on how to fix this? Obviously this lens is too valuable to trash and I have fixed lenses before. I pulled the mounting ring off the back but was not able to see anything obviously wrong and decided to get more information before trying anything further.

12-02-2012, 06:49 PM   #2
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If the ring turns freely, then it could be that the camera is in MF mode, or that there's something wrong with the drive shaft on the mount, preventing it from locking. Could also be something inside the lens that's disengaged some gears...

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12-03-2012, 09:36 PM   #3
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No, it's not the camera. The focus ring turns without the lens changing focus. The forward optical assembly does not turn or extend as it normally would. Actually I think that the lens got squeezed too hard, front to back, while it was in the bag and something was damaged in the focus mechanism.

Just wondering if there was someone out there who's experience I could benefit from.

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