DA* 60-250, automatically switches to screw drive

Samoht · 02-16-2018, 04:38 AM

Hi,

I've got a slightly different issue, I've got a DA* 60-250 that automatically switches to screw drive. Bought it before Christmas and it is a demo ex from the distributor here in Sweden, was broken from the start due to some tube being loose inside causing zoom to get stuck. It was also sent to Germany to calibrate the lens elements.

Has happened twice the last 1,5 week but I cannot force it to happen, yesterday it went from SDM to screw drive after being in sleep mode. The first time it happened was while using it. Contacts are clean but I cleaned them again just to be sure, of course both on lens and on camera. When it happens the only way to get it back to SDM is to de-attach and attach the lens, doesn't work to restart camera or remove battery.
Camera I've used is a K-3II, will try it on my K-3 for a while and mount a DA* 50-135 on the K-3II just to try to see if it is the lens or the camera that are causing this auto switch to screw drive-mode. Has anyone heard of this issue before and has any ideas?

**BigMackCam** · 02-16-2018, 04:49 AM

This is very interesting... the DA*60-250 is, as far as I know, the only lens that can't be converted to screw-drive. Does your lens actually focus when it switches to screw-drive, or do you simply hear the motor running?

I'm wondering if one or both of the AF contacts on your lens is dirty or damaged, and perhaps the camera and lens resort to screw-drive when that connection is lost. Just a thought. If that's the case, it might mean some others here could convert their DA*60-250 to screw-drive by covering those contacts or removing them altogether.

Samoht · 02-16-2018, 05:08 AM

The little I've tested in screw drive mode it seems to focus as it should, took some photos yesterday in screw drive mode and it focuses a bit faster than with SDM. When it happened yesterday it was at dusk and I got the impression that it didn't hunt as much as with SDM but then again I only took a few photos so can't really tell.

I've cleaned the contacts with a piece of micro fiber cloth, haven't used any cleaning fluid though. Cleaned it again with a brand new micro fiber cloth today and it got a little bit dirty, the contacts at least looks very clean now. Which of the contacts are the AF contacts?

As I understand if you mount a SDM lens on a camera that doesn't support SDM it will automatically go to screw drive (except for the DA* 55 for obvious reasons), perhaps it has something to do with AF contacts as you mentioned.

**BigMackCam** · 02-16-2018, 05:12 AM

The AF contacts are the two oblong shaped yellow metal pieces on the inner edge of the mount, set into black plastic. Does that make sense?

Samoht · 02-16-2018, 05:22 AM

Yes, makes perfectly sense. Hadn't cleaned those. Thanks!
Those two contacts looked however quite clean, was the outer ring and contacts that were a bit dirty. I'm not sure but one of the two AF contacts on the lens might have had some dirt on it. Used the same cloth as for the outer contacts and didn't really looked so that I used a perfectly clean area of the cloth so the cloth had some small mount of dirt after cleaning AF contacts, not sure if the dirt was already on the cloth or came from the AF contacts.

Will try it again on the K-3II before putting it on my K-3.

normhead · 02-16-2018, 06:38 AM

I once had to replace the contacts on my 60-250 when AF quit working, one of the gold contacts had broken on one side and no longer made contact with the camera body. Th replacement part was relatively inexpensive and I replaced it myself. I Just ordered the part from Sun Camera, here in Canada. Two screws and no dress, a very easy replacement.

**scc** · 02-16-2018, 11:19 AM

Hi,
Does it mean that covering those contacts with a piece of tape will trigger the screwdrive mode on a body that operates both SDM and screwdrive ?

**UncleVanya** · 02-16-2018, 11:28 AM

Originally posted by scc

Hi,
Does it mean that covering those contacts with a piece of tape will trigger the screwdrive mode on a body that operates both SDM and screwdrive ?

Past tests with the 16-50 and 50-135 didn't work that way. That was the earliest attempt to find a solution. In past experiments covering the SDM contacts did nothing to disable SDM. I would think the more likely scenario is that either the data pin is dirty and the data communicated by the lens about the capability of the lens to do SDM is getting corrupted, or the camera itself is having a hiccup when it reads the lens data.

**BigMackCam** · 02-16-2018, 11:28 AM

Originally posted by scc

Does it mean that covering those contacts with a piece of tape will trigger the screwdrive mode on a body that operates both SDM and screwdrive ?

That's what I was thinking. Or, where the conversion is to be a permanent one, remove those contacts altogether. But I guess we need to find out if taping over works first

normhead · 02-16-2018, 11:34 AM

Originally posted by BigMackCam

That's what I was thinking. Or, where the conversion is to be a permanent one, remove those contacts altogether. But I guess we need to find out if taping over works first

When the contacts didn't work on my DA* 60-250, screw drive did not kick in, I had to replace the contacts. But that was a few years ago. Maybe there's been a firmware change or something. The part is the same in the DA 18-135 and I suspect many other lenses. At one point I was considering swapping out the DA 18-135 one and putting it into the 60-250, because I really wanted the 60-250 that day.

**UncleVanya** · 02-16-2018, 11:35 AM

I will tell you that in past experiments to convert the SDM 60-250 I have gotten it to focus using screw drive - it was however brief and unreliable. It would work for about 2 - or 3 seconds or 2-3 button presses - and then suddenly revert to SDM. Once it reverted powering off and back on was required to get it to try to use screw drive again - and it was not 100% sure that it would even briefly work. This was done with a working SDM lens.

We do know of ONE Russian modified DA* 60-250 that works in screw drive but it may have had hardware modifications since even attempts to review that Lens ROM has not yielded any data that would help with converting other 60-250 lenses.

**scc** · 02-16-2018, 11:51 AM

Since the lens operates in screwdrive mode with a non SDM body, I guess the lens detects the body SDM contacts? Or some other information (or lack thereof) from the body is necessary to shift from SDM to screwdrive? Did anybody try masking the contacts on the body instead of on the lens?

**grahame** · 02-16-2018, 12:36 PM

That is very interesting. A dirty SDM contact will not automatically activate screw drive AF on most cameras, including K10D, K-X, K-R, k7, K5, K30, KS1 KS2 and K5II. I put a tape on the contacts and it only stopped SDM, but no AF at all. The only camera I know does that is K-01.
I don't have a k3. maybe it has a different design and allows that? Can any other K-3 owner confirm that?

**BigMackCam** · 02-16-2018, 12:42 PM

Originally posted by grahame

That is very interesting. dirty SDM contacts will not automatically active screw drive AF on most cameras, including K10D, K-X, K-R, k7, K5, K30, KS1 KS2 and K5II. I put a tape on the contacts and it only stopped SDM, but now AF at all. The only camera I know does that is K-01.
I don't have a k3. maybe it has a different design and allows that? Can any other K-3 owner confirm that?

I'll try it out over the weekend

normhead · 02-16-2018, 03:04 PM

Originally posted by grahame

That is very interesting. A dirty SDM contact will not automatically activate screw drive AF on most cameras, including K10D, K-X, K-R, k7, K5, K30, KS1 KS2 and K5II. I put a tape on the contacts and it only stopped SDM, but no AF at all. The only camera I know does that is K-01.
I don't have a k3. maybe it has a different design and allows that? Can any other K-3 owner confirm that?

My K-3 definitely didn't but maybe with updated firmware, who knows? Mine is off for repairs at the moment.

02-16-2018, 04:38 AM	#1
Samoht Forum Member Join Date: Jul 2012 Location: Härjedalen, Sweden Posts: 72	*DA 60-250, automatically switches to screw drive** Hi, I've got a slightly different issue, I've got a DA* 60-250 that automatically switches to screw drive. Bought it before Christmas and it is a demo ex from the distributor here in Sweden, was broken from the start due to some tube being loose inside causing zoom to get stuck. It was also sent to Germany to calibrate the lens elements. Has happened twice the last 1,5 week but I cannot force it to happen, yesterday it went from SDM to screw drive after being in sleep mode. The first time it happened was while using it. Contacts are clean but I cleaned them again just to be sure, of course both on lens and on camera. When it happens the only way to get it back to SDM is to de-attach and attach the lens, doesn't work to restart camera or remove battery. Camera I've used is a K-3II, will try it on my K-3 for a while and mount a DA* 50-135 on the K-3II just to try to see if it is the lens or the camera that are causing this auto switch to screw drive-mode. Has anyone heard of this issue before and has any ideas?

02-16-2018, 12:36 PM	#13
grahame Loyal Site Supporter Join Date: Aug 2011 Photos: Albums Posts: 2,041	That is very interesting. A dirty SDM contact will not automatically activate screw drive AF on most cameras, including K10D, K-X, K-R, k7, K5, K30, KS1 KS2 and K5II. I put a tape on the contacts and it only stopped SDM, but no AF at all. The only camera I know does that is K-01. I don't have a k3. maybe it has a different design and allows that? Can any other K-3 owner confirm that? Last edited by grahame; 02-16-2018 at 01:11 PM.

02-16-2018, 03:04 PM	#15
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by grahame That is very interesting. A dirty SDM contact will not automatically activate screw drive AF on most cameras, including K10D, K-X, K-R, k7, K5, K30, KS1 KS2 and K5II. I put a tape on the contacts and it only stopped SDM, but no AF at all. The only camera I know does that is K-01. I don't have a k3. maybe it has a different design and allows that? Can any other K-3 owner confirm that? My K-3 definitely didn't but maybe with updated firmware, who knows? Mine is off for repairs at the moment. Last edited by normhead; 02-16-2018 at 07:43 PM.

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02-16-2018, 04:49 AM	#2
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,703	This is very interesting... the DA60-250 is, as far as I know, the only lens that can't be converted to screw-drive. Does your lens actually focus when it switches to screw-drive, or do you simply hear the motor running? I'm wondering if one or both of the AF contacts on your lens is dirty or damaged, and perhaps the camera and lens resort to screw-drive when that connection is lost. Just a thought. If that's the case, it might mean some others here could convert their DA60-250 to screw-drive by covering those contacts or removing them altogether.

02-16-2018, 05:08 AM	#3
Samoht Forum Member Join Date: Jul 2012 Location: Härjedalen, Sweden Posts: 72 Original Poster	The little I've tested in screw drive mode it seems to focus as it should, took some photos yesterday in screw drive mode and it focuses a bit faster than with SDM. When it happened yesterday it was at dusk and I got the impression that it didn't hunt as much as with SDM but then again I only took a few photos so can't really tell. I've cleaned the contacts with a piece of micro fiber cloth, haven't used any cleaning fluid though. Cleaned it again with a brand new micro fiber cloth today and it got a little bit dirty, the contacts at least looks very clean now. Which of the contacts are the AF contacts? As I understand if you mount a SDM lens on a camera that doesn't support SDM it will automatically go to screw drive (except for the DA* 55 for obvious reasons), perhaps it has something to do with AF contacts as you mentioned.

02-16-2018, 05:12 AM	#4
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,703	The AF contacts are the two oblong shaped yellow metal pieces on the inner edge of the mount, set into black plastic. Does that make sense?

02-16-2018, 05:22 AM	#5
Samoht Forum Member Join Date: Jul 2012 Location: Härjedalen, Sweden Posts: 72 Original Poster	Yes, makes perfectly sense. Hadn't cleaned those. Thanks! Those two contacts looked however quite clean, was the outer ring and contacts that were a bit dirty. I'm not sure but one of the two AF contacts on the lens might have had some dirt on it. Used the same cloth as for the outer contacts and didn't really looked so that I used a perfectly clean area of the cloth so the cloth had some small mount of dirt after cleaning AF contacts, not sure if the dirt was already on the cloth or came from the AF contacts. Will try it again on the K-3II before putting it on my K-3.

02-16-2018, 06:38 AM	#6
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	I once had to replace the contacts on my 60-250 when AF quit working, one of the gold contacts had broken on one side and no longer made contact with the camera body. Th replacement part was relatively inexpensive and I replaced it myself. I Just ordered the part from Sun Camera, here in Canada. Two screws and no dress, a very easy replacement.

02-16-2018, 11:19 AM	#7
scc Loyal Site Supporter Join Date: Dec 2012 Posts: 165	Hi, Does it mean that covering those contacts with a piece of tape will trigger the screwdrive mode on a body that operates both SDM and screwdrive ?

02-16-2018, 11:28 AM	#8
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,467	Originally posted by scc Hi, Does it mean that covering those contacts with a piece of tape will trigger the screwdrive mode on a body that operates both SDM and screwdrive ? Past tests with the 16-50 and 50-135 didn't work that way. That was the earliest attempt to find a solution. In past experiments covering the SDM contacts did nothing to disable SDM. I would think the more likely scenario is that either the data pin is dirty and the data communicated by the lens about the capability of the lens to do SDM is getting corrupted, or the camera itself is having a hiccup when it reads the lens data.

02-16-2018, 11:28 AM	#9
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,703	Originally posted by scc Does it mean that covering those contacts with a piece of tape will trigger the screwdrive mode on a body that operates both SDM and screwdrive ? That's what I was thinking. Or, where the conversion is to be a permanent one, remove those contacts altogether. But I guess we need to find out if taping over works first

02-16-2018, 11:34 AM	#10
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by BigMackCam That's what I was thinking. Or, where the conversion is to be a permanent one, remove those contacts altogether. But I guess we need to find out if taping over works first When the contacts didn't work on my DA* 60-250, screw drive did not kick in, I had to replace the contacts. But that was a few years ago. Maybe there's been a firmware change or something. The part is the same in the DA 18-135 and I suspect many other lenses. At one point I was considering swapping out the DA 18-135 one and putting it into the 60-250, because I really wanted the 60-250 that day.

02-16-2018, 11:35 AM	#11
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,467	I will tell you that in past experiments to convert the SDM 60-250 I have gotten it to focus using screw drive - it was however brief and unreliable. It would work for about 2 - or 3 seconds or 2-3 button presses - and then suddenly revert to SDM. Once it reverted powering off and back on was required to get it to try to use screw drive again - and it was not 100% sure that it would even briefly work. This was done with a working SDM lens. We do know of ONE Russian modified DA* 60-250 that works in screw drive but it may have had hardware modifications since even attempts to review that Lens ROM has not yielded any data that would help with converting other 60-250 lenses.

02-16-2018, 11:51 AM	#12
scc Loyal Site Supporter Join Date: Dec 2012 Posts: 165	Since the lens operates in screwdrive mode with a non SDM body, I guess the lens detects the body SDM contacts? Or some other information (or lack thereof) from the body is necessary to shift from SDM to screwdrive? Did anybody try masking the contacts on the body instead of on the lens?

02-16-2018, 12:42 PM	#14
BigMackCam Digitiser of Film Join Date: Mar 2010 Location: North East of England Posts: 20,703	Originally posted by grahame That is very interesting. dirty SDM contacts will not automatically active screw drive AF on most cameras, including K10D, K-X, K-R, k7, K5, K30, KS1 KS2 and K5II. I put a tape on the contacts and it only stopped SDM, but now AF at all. The only camera I know does that is K-01. I don't have a k3. maybe it has a different design and allows that? Can any other K-3 owner confirm that? I'll try it out over the weekend