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08-07-2014, 09:13 PM   #1
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Questions about DA* 16-50

Hi all,


I purchased a used DA*16-50 to use on my K30 and the autofocus doesn't seem to be working.. I was wondering if someone could answer some questions about this lens. When I have it on full auto, should I not hear/feel it trying to focus? With the quick shift is there a wrong way to turn the focus ring. I thought I understood that you press the shutter half way to have it auto focus and then when its locked you can turn the focus ring to fine tune it(making sure the shutter release is kept half way down) Can it be turned all the way around or should it be turned all the way around? should I be rotating it in either clockwise or counter clockwise to focus? The copy I have seems to almost drag if I have it on auto or manual. The focus ring doesn't seem freely move as some of my other lenses. It seems to work fine on manual focus. I have returned it to the seller, but I am just wondering for the little bit I saved on price if I should just bite the bullet and buy new and maybe have better luck?

08-07-2014, 09:55 PM   #2
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QuoteOriginally posted by fewing1 Quote
d the autofocus doesn't seem to be working.. I was wondering if someone could answer some questions about this lens. When I have it on full auto, should I not hear/feel it trying to focus?
Maybe, it is very quiet so maybe not. But you should definitely see it move into focus.
QuoteOriginally posted by fewing1 Quote
With the quick shift is there a wrong way to turn the focus ring. I thought I understood that you press the shutter half way to have it auto focus and then when its locked you can turn the focus ring to fine tune it(making sure the shutter release is kept half way down)
No, there is no wrong way. It goes either direction.
QuoteOriginally posted by fewing1 Quote
Can it be turned all the way around or should it be turned all the way around? should I be rotating it in either clockwise or counter clockwise to focus?
It goes all the way around, though that also means you can turn the ring further than infinity, but of course the lens stops there, just the ring continues to turn, there is no 'stop' as on manual lenses.
QuoteOriginally posted by fewing1 Quote
The copy I have seems to almost drag if I have it on auto or manual. The focus ring doesn't seem freely move as some of my other lenses.
That seems odd, mine has no drag at all, just butter smooth. Though you should feel the slight 'stop' when it comes to the end of the focus range. Just a little click and then the ring continues to turn. Watch the distance scale as you turn and you can see it hits the stop and just keeps going.

I have bought most of my lenses used, but I did buy the DA*16-50 new. And ended up with a bad SDM motor that required repair. Still after 10,000 images with it I am not complaining. But at this point I would not buy one used, only new with a warranty. Just my opinion.
08-07-2014, 09:56 PM   #3
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I suspect the SDM autofocus system has failed.
08-08-2014, 12:23 AM   #4
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QuoteOriginally posted by jatrax Quote
But at this point I would not buy one used, only new with a warranty. Just my opinion.
Agree. I read a lot of forum threads before buying my copy new, mainly because of the SDM issues in older copies.

08-08-2014, 12:30 AM   #5
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do you have another SDM lens? On my K7 the SDM motor inside the camera was broken so SDM lenses didn't work.
08-08-2014, 08:09 AM   #6
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QuoteOriginally posted by Franc Quote
On my K7 the SDM motor inside the camera was broken so SDM lenses didn't work.
Hmm, there is no SDM motor in the camera, it is in the lens.
08-08-2014, 10:25 AM   #7
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Thanks for the replies, thought I was perhaps losing my mind. and no this is the first quick shift lens that I have purchased, so I didn't have anything to reference it to.
08-08-2014, 11:47 AM   #8
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QuoteOriginally posted by jatrax Quote
Hmm, there is no SDM motor in the camera, it is in the lens.
there is that thing then that activates the lens SDM. On my K7 repair bill it said SDM

08-08-2014, 12:01 PM   #9
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QuoteOriginally posted by Franc Quote
there is that thing then that activates the lens SDM. On my K7 repair bill it said SDM
SDM contacts maybe? Those are the little brass contacts that used to be used for the powerzoom lenses. They now provide the power for the SDM motor in the lens.
08-12-2014, 12:50 AM   #10
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it was the complete unit and not just the contacts
08-12-2014, 09:50 AM   #11
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QuoteOriginally posted by fewing1 Quote
Hi all,


I purchased a used DA*16-50 to use on my K30 and the autofocus doesn't seem to be working.. I was wondering if someone could answer some questions about this lens. When I have it on full auto, should I not hear/feel it trying to focus? With the quick shift is there a wrong way to turn the focus ring. I thought I understood that you press the shutter half way to have it auto focus and then when its locked you can turn the focus ring to fine tune it(making sure the shutter release is kept half way down) Can it be turned all the way around or should it be turned all the way around? should I be rotating it in either clockwise or counter clockwise to focus? The copy I have seems to almost drag if I have it on auto or manual. The focus ring doesn't seem freely move as some of my other lenses. It seems to work fine on manual focus. I have returned it to the seller, but I am just wondering for the little bit I saved on price if I should just bite the bullet and buy new and maybe have better luck?
Likely an SDM failure, common on the early 16-50's.

There's no wrong way to eat a Reese's. I mean, to turn a focus ring.
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