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Message: <blockquote data-quote="Bob Blaylock" data-source="post: 539777" data-attributes="member: 16749">Paging [USER=41018]@D200freak[/USER] or anyone else who might have the knowledge to help me here…  Some time after the previous conclusion of this thread, a new issue has arisen.  It's a minor annoyance, with which I can live, but if there's any chance of an easy fix, I'd sure like to know about it.  This affects my D3200, combined with the stock 18-55mm lens that came with it.  I do not have any other bodies that are modern enough to be compatible with this lens, nor do I have any other AF-S lenses, so I cannot definitely establish whether it is the lens or the camera that is at fault; but I suspect the lens.  If the camera has been unused for more than a few hours, autofocus doesn't work.  I push the shutter release, and the lens makes no apparent effort to focus.  At that point, if I grasp the focus ring on the lens, and apply the slightest bit of counterclockwise (as seen from the direction of one using the camera) force, while pressing the button, then the autofocus begins to work, and after that point, it will continue to work reliably until the next time the camera goes for very long without being used.  It makes me think of an issue that can arise with more primitive types of electric motors, where a dirty or worn spot on a commutator can create a “dead spot”, where, if the motor stops on that spot, it will not restart unless some external effort is applied to turn it away from that spot.  I'm pretty sure that the type of motor that is involved here does not have commutators or brushes, or anything corresponding thereto, and should not be subject to that particular type of issue.  Given what little understanding I can glean about how the Silentwave motor works, it is not clear to me what could cause this sort of issue with it.  I'm assuming that the fact that applying a slight amount of the right force gets it working again, indicates that the issue is occurring in the motor itself, and not in any of the supporting electronics.  Some things that may be relevant.<ul> <li data-xf-list-type="ul">I was careful when <a href="http://nikonites.com/d5200/32824-please-help-noob-question-distant-object-focus.html#post493995" target="_blank">I engraved a set of infinity focusing marks on this lens</a>, but I wonder, nevertheless, whether some plastic and/or metal filings from that engraving process might have found their way into the motor, and be causing this issue.</li> <li data-xf-list-type="ul">When the camera is being carried in its bag, it is face-down, and the weight of the camera would likely rest mostly on the front of the lens.  I should think that a camera lens—especially a stock “kit lens” that is likely to be left on the camera most of the time—should be engineered with the expectation that the front of it will often be supporting the weight of itself and the camera; and should be designed to withstand this without being damaged.  But then, if the lens was not engineered with this being taken into account, it is not at all difficult for me to imagine how the focusing mechanism might be damaged from this.</li> <li data-xf-list-type="ul">This lens was not on my camera, when my camera fell as described at the start of this thread; so assuming the issue is with the lens rather than with the camera body, this fall is not a factor.</li> </ul></blockquote>

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