Stuck SDM simple solution that worked

transam879 · 07-13-2015, 11:57 AM

Just wanted to put out here that my AF motor on my DA* 300 (I'm guessing) got stuck. Thought it was a dead motor. I couldn't AF or MF as even turning the focus ring didn't work. I took a screwdriver and turned the screwdrive mechanism on the lens mount (can't remember if it was clockwise or counterclockwise) a couple times and the AF and MF has been working on the lens ever since. I delayed posting this just to make sure it continued to work, which it has. I apologize if this has been posted already but couldn't find anything on here or the Internet that addressed this other than partially disassembling the lens mount, something I preferred not to do. Just wanted to post it in case someone had a similar issue.

shaolen · 07-13-2015, 12:22 PM

yes I had this problem a couple years ago with a DA* 50-135mm and did that same thing and it worked. If I find the thread ill let you know. Not sure if this is the same problem everyone has with SDM

---------- Post added 07-13-15 at 11:26 AM ----------

if it is the solution to all SDM issues then a lot of money has been waisted

Venom3300 · 07-13-2015, 12:42 PM

Interesting. Makes you wonder if the screw drive mechanism is hanging on the SDM mechanism causing it to fail.

IchabodCrane · 07-13-2015, 12:52 PM

Originally posted by Venom3300

Interesting. Makes you wonder if the screw drive mechanism is hanging on the SDM mechanism causing it to fail.

There still have been SDM failures on lenses without screw-driven focus mechanisms but maybe the incidence has been less?

Edgar_in_Indy · 07-13-2015, 05:13 PM

Sounds like it's time to sell!

tedi051 · 07-14-2015, 01:00 AM

I had this problem twice with my DA* 300mm. I cleaned contacts on a lens mount with lens cleaner kit and that resolved problem both times. I presume that this problem occured when I leave my 300mm lens on a camera body for longer time. If I remember well I think that I could MF with my lens but no AF.

Blacknight659 · 05-16-2016, 01:58 PM

Originally posted by transam879

Just wanted to put out here that my AF motor on my DA* 300 (I'm guessing) got stuck. Thought it was a dead motor. I couldn't AF or MF as even turning the focus ring didn't work. I took a screwdriver and turned the screwdrive mechanism on the lens mount (can't remember if it was clockwise or counterclockwise) a couple times and the AF and MF has been working on the lens ever since. I delayed posting this just to make sure it continued to work, which it has. I apologize if this has been posted already but couldn't find anything on here or the Internet that addressed this other than partially disassembling the lens mount, something I preferred not to do. Just wanted to post it in case someone had a similar issue.

I wanted to start this discussion back up if possible. My 50-135 was Stuck, SDM and MF would NOT work. I attached to a screwdrive Film body and the focusing started working. After playing with it a little, I then put it back on my K-5iis, It was still stuck both SDM and MF. I kept spinning MF and hitting SDM and finally it started working.

Is this the Motor or something else "broken" in the lens?

07-13-2015, 11:57 AM	#1
transam879 Veteran Member Join Date: Feb 2011 Location: Syracuse, NY Posts: 651	Stuck SDM simple solution that worked Just wanted to put out here that my AF motor on my DA* 300 (I'm guessing) got stuck. Thought it was a dead motor. I couldn't AF or MF as even turning the focus ring didn't work. I took a screwdriver and turned the screwdrive mechanism on the lens mount (can't remember if it was clockwise or counterclockwise) a couple times and the AF and MF has been working on the lens ever since. I delayed posting this just to make sure it continued to work, which it has. I apologize if this has been posted already but couldn't find anything on here or the Internet that addressed this other than partially disassembling the lens mount, something I preferred not to do. Just wanted to post it in case someone had a similar issue.

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07-13-2015, 12:22 PM	#2
shaolen Veteran Member Join Date: May 2012 Location: Phoenix AZ Posts: 1,047	yes I had this problem a couple years ago with a DA* 50-135mm and did that same thing and it worked. If I find the thread ill let you know. Not sure if this is the same problem everyone has with SDM ---------- Post added 07-13-15 at 11:26 AM ---------- if it is the solution to all SDM issues then a lot of money has been waisted

07-13-2015, 12:42 PM	#3
Venom3300 Veteran Member Join Date: Jul 2014 Posts: 714	Interesting. Makes you wonder if the screw drive mechanism is hanging on the SDM mechanism causing it to fail.

07-13-2015, 12:52 PM	#4
IchabodCrane Veteran Member Join Date: Sep 2012 Photos: Gallery \| Albums Posts: 1,728	Originally posted by Venom3300 Interesting. Makes you wonder if the screw drive mechanism is hanging on the SDM mechanism causing it to fail. There still have been SDM failures on lenses without screw-driven focus mechanisms but maybe the incidence has been less?

07-13-2015, 05:13 PM	#5
Edgar_in_Indy Veteran Member Join Date: May 2010 Location: Indiana, USA Photos: Gallery Posts: 2,685	Sounds like it's time to sell!

07-14-2015, 01:00 AM	#6
tedi051 New Member Join Date: Oct 2009 Location: Rijeka Photos: Gallery \| Albums Posts: 15	I had this problem twice with my DA* 300mm. I cleaned contacts on a lens mount with lens cleaner kit and that resolved problem both times. I presume that this problem occured when I leave my 300mm lens on a camera body for longer time. If I remember well I think that I could MF with my lens but no AF.

05-16-2016, 01:58 PM	#7
Blacknight659 Veteran Member Join Date: Aug 2013 Photos: Gallery \| Albums Posts: 731	Originally posted by transam879 Just wanted to put out here that my AF motor on my DA* 300 (I'm guessing) got stuck. Thought it was a dead motor. I couldn't AF or MF as even turning the focus ring didn't work. I took a screwdriver and turned the screwdrive mechanism on the lens mount (can't remember if it was clockwise or counterclockwise) a couple times and the AF and MF has been working on the lens ever since. I delayed posting this just to make sure it continued to work, which it has. I apologize if this has been posted already but couldn't find anything on here or the Internet that addressed this other than partially disassembling the lens mount, something I preferred not to do. Just wanted to post it in case someone had a similar issue. I wanted to start this discussion back up if possible. My 50-135 was Stuck, SDM and MF would NOT work. I attached to a screwdrive Film body and the focusing started working. After playing with it a little, I then put it back on my K-5iis, It was still stuck both SDM and MF. I kept spinning MF and hitting SDM and finally it started working. Is this the Motor or something else "broken" in the lens?