Problems with Macro lenses

**UncleVanya** · 12-28-2020, 09:51 AM

Originally posted by tibbitts

I didn't think any Pentax macro lenses even had a focus motor, much less one of the failure-prone SDM motors.

Agreed.

normhead · 12-28-2020, 10:02 AM - **1 Like**

If there is any issue at all here, it's tha macro lenses achieve macro by extending the front elements out further than non macro lenses. More throw in the focussing system will mean more dust and moisture inside the lens. I have no idea if that's true for WR, dust sealed lenses. I suspect even if once true, it's now meaningless for folks buying current gear. For older gear, any lens can have dust or fungus.

We have two macros non WR that have been immersed I water. We slightly disassembled them and dried them out and have and no issues with them. I have no insight on what it takes to actually get mold.

I did get mold in one of my first zooms. I took it on a 10 day canoe trip 40 years ago, so living out doors for 10 days, no waterproof case, probably taking on moisture every morning and evening. No dust or water seals. Just in a regular camera bag, and stored outside my tent. But hey, everyone is dumb at least once.

I don't do that kind of stuff anymore.

stevebrot · 12-28-2020, 10:22 AM

Originally posted by dlhawes

though it's got the SMC motor that seems to have caused a lot of trouble.

Yep, the multi-coating on the gear train flaked off within a few weeks of manufacture, resulting in a massive recall.

Steve

dlhawes · 12-28-2020, 11:32 AM

Ah, yes, my confusion. Thanks for that information. Either way, the lens is terrific.

Originally posted by UncleVanya

??????

The FA 100 f2.8 has a screw drive focus system using an in body motor not an in lens motor ( as does the F and DA version including the WR version.) There are no Pentax branded macro lenses with any other type of focus system.

SMC is a coating on the lens elements. Did you mix this up with SDM? SDM is the silent motor system used in some lenses. The early SDM was prone to failure, the newer versions not so much.

Bertrand3000 · 12-28-2020, 01:33 PM - **1 Like**

Originally posted by tibbitts

I didn't think any Pentax macro lenses even had a focus motor, much less one of the failure-prone SDM motors.

To clarify, the only lenses which can suffer from SDM failure are the following :

- DA* 16-50 (but can be converted to screw-drive)
- DA* 50-135 (but can be converted to screw-drive)
- DA* 200 (but can be converted to screw-drive)
- DA* 300 (but can be converted to screw-drive)
- DA* 55
- DA* 60-250
- DA 17-70

Besides, recent version of those lenses are supposed to have much more robust SDM motors and thus would be much less likely to fail.

Other SDM lenses, or any other motor (screw drive, DC, PLM) are not affected.

**UncleVanya** · 12-28-2020, 01:53 PM - **1 Like**

Originally posted by Bertrand3000

To clarify, the only lenses which can suffer from SDM failure are the following :

- DA* 16-50 (but can be converted to screw-drive)
- DA* 50-135 (but can be converted to screw-drive)
- DA* 60-250
- DA 17-70

Besides, recent version of those lenses are supposed to have much more robust SDM motors and thus would be much less likely to fail.

Other SDM lenses, or any other motor (screw drive, DC, PLM) are not affected.

That list is incomplete:

DA* 200 (can be converted) I have converted at least 5 or 6
DA* 300 (can be converted) See above.
DA* 55 (cannot be converted) My copy (thank goodness) continues to work normally.

These are just off the top of my mind. I'm not sure there are not others I have forgotten.

Bertrand3000 · 12-28-2020, 01:56 PM

Originally posted by UncleVanya

That list is incomplete:

Thanks for adding, I fixed my post. You are without any doubt the person who knows the most about this subject.

normhead · 12-28-2020, 02:00 PM

I would think any in lens motor from any system would fail eventually.The beauty of screw drive was always, you get a new lens motor every time you upgrade your camera body.

Someday, I'll ask the guy at Sun Camera if the SDM motors fail more than one's from other systems.

tibbitts · 12-28-2020, 02:30 PM

Originally posted by normhead

I would think any in lens motor from any system would fail eventually.The beauty of screw drive was always, you get a new lens motor every time you upgrade your camera body.

That's actually a good point. I guess there must be an engineering reason why screw drive can't be as accurate or quiet or fast, but the appeal of always getting a focus performance upgrade with every new body seems appealing.

I do find it annoying that Pentax doesn't include a focus drive selection feature for those lenses with both screw drive and focus motors.

**UncleVanya** · 12-28-2020, 02:46 PM

Originally posted by Bertrand3000

Thanks for adding, I fixed my post. You are without any doubt the person who knows the most about this subject.

LOL
I doubt that. I may know the most about converting the four lenses I convert - but not anything more than this.

**pentaxus** · 12-28-2020, 08:24 PM

I have seen a few 100mm f/4 lenses with separated lens elements in the front group. Historically, when lenses used Canada balsam as cement, you might see variation in permanence with different years. I'm not sure when companies stopped using Canada Balsam.

**Apet-Sure** · 12-29-2020, 02:59 PM

Originally posted by UncleVanya

That list is incomplete

A* 200 (can be converted) I have converted at least 5 or 6DA* 300 (can be converted) See above.DA* 55 (cannot be converted) My copy (thank goodness) continues to work normally.These are just off the top of my mind. I'm not sure there are not others I have forgotten.

Don't forget the DA* 60-250mm SDM. Mine has failed, and apparently cannot be converted to screw-drive.

**UncleVanya** · 12-29-2020, 03:01 PM

Originally posted by Apet-Sure

Don't forget the DA* 60-250mm SDM. Mine has failed, and apparently cannot be converted to screw-drive.

That’s already listed in the post I quoted.

**Apet-Sure** · 12-29-2020, 03:35 PM

Hmmm... I didn't see it when I read post #20, and I expected to. Oh well; mine's still dead. Manual focusing is usually not a problem when I use it, and I got it at a great price from a PF member, so I'm content.

**UncleVanya** · 12-29-2020, 07:28 PM

Originally posted by Apet-Sure

Hmmm... I didn't see it when I read post #20, and I expected to. Oh well; mine's still dead. Manual focusing is usually not a problem when I use it, and I got it at a great price from a PF member, so I'm content.

I really wish it could be fixed.

12-28-2020, 10:02 AM - 1 Like	#17
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	If there is any issue at all here, it's tha macro lenses achieve macro by extending the front elements out further than non macro lenses. More throw in the focussing system will mean more dust and moisture inside the lens. I have no idea if that's true for WR, dust sealed lenses. I suspect even if once true, it's now meaningless for folks buying current gear. For older gear, any lens can have dust or fungus. We have two macros non WR that have been immersed I water. We slightly disassembled them and dried them out and have and no issues with them. I have no insight on what it takes to actually get mold. I did get mold in one of my first zooms. I took it on a 10 day canoe trip 40 years ago, so living out doors for 10 days, no waterproof case, probably taking on moisture every morning and evening. No dust or water seals. Just in a regular camera bag, and stored outside my tent. But hey, everyone is dumb at least once. I don't do that kind of stuff anymore. Last edited by normhead; 12-28-2020 at 10:13 AM.

12-28-2020, 01:33 PM - 1 Like	#20
Bertrand3000 Veteran Member Join Date: Feb 2019 Posts: 2,009	Originally posted by tibbitts I didn't think any Pentax macro lenses even had a focus motor, much less one of the failure-prone SDM motors. To clarify, the only lenses which can suffer from SDM failure are the following : - DA* 16-50 (but can be converted to screw-drive) - DA* 50-135 (but can be converted to screw-drive) - DA* 200 (but can be converted to screw-drive) - DA* 300 (but can be converted to screw-drive) - DA* 55 - DA* 60-250 - DA 17-70 Besides, recent version of those lenses are supposed to have much more robust SDM motors and thus would be much less likely to fail. Other SDM lenses, or any other motor (screw drive, DC, PLM) are not affected. Last edited by Bertrand3000; 12-28-2020 at 01:57 PM.

12-29-2020, 02:59 PM	#27
Apet-Sure Site Supporter Join Date: Dec 2015 Location: Goldsboro North Carolina Photos: Gallery \| Albums Posts: 2,872	Originally posted by UncleVanya That list is incompleteA* 200 (can be converted) I have converted at least 5 or 6DA* 300 (can be converted) See above.DA* 55 (cannot be converted) My copy (thank goodness) continues to work normally.These are just off the top of my mind. I'm not sure there are not others I have forgotten. Don't forget the DA* 60-250mm SDM. Mine has failed, and apparently cannot be converted to screw-drive.

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12-28-2020, 09:51 AM	#16
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,460	Originally posted by tibbitts I didn't think any Pentax macro lenses even had a focus motor, much less one of the failure-prone SDM motors. Agreed.

12-28-2020, 10:22 AM	#18
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by dlhawes though it's got the SMC motor that seems to have caused a lot of trouble. Yep, the multi-coating on the gear train flaked off within a few weeks of manufacture, resulting in a massive recall. Steve

12-28-2020, 11:32 AM	#19
dlhawes Guest	Ah, yes, my confusion. Thanks for that information. Either way, the lens is terrific. Originally posted by UncleVanya ?????? The FA 100 f2.8 has a screw drive focus system using an in body motor not an in lens motor ( as does the F and DA version including the WR version.) There are no Pentax branded macro lenses with any other type of focus system. SMC is a coating on the lens elements. Did you mix this up with SDM? SDM is the silent motor system used in some lenses. The early SDM was prone to failure, the newer versions not so much.

12-28-2020, 01:53 PM - 1 Like	#21
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,460	Originally posted by Bertrand3000 To clarify, the only lenses which can suffer from SDM failure are the following : - DA* 16-50 (but can be converted to screw-drive) - DA* 50-135 (but can be converted to screw-drive) - DA* 60-250 - DA 17-70 Besides, recent version of those lenses are supposed to have much more robust SDM motors and thus would be much less likely to fail. Other SDM lenses, or any other motor (screw drive, DC, PLM) are not affected. That list is incomplete: DA* 200 (can be converted) I have converted at least 5 or 6 DA* 300 (can be converted) See above. DA* 55 (cannot be converted) My copy (thank goodness) continues to work normally. These are just off the top of my mind. I'm not sure there are not others I have forgotten.

12-28-2020, 01:56 PM	#22
Bertrand3000 Veteran Member Join Date: Feb 2019 Posts: 2,009	Originally posted by UncleVanya That list is incomplete: Thanks for adding, I fixed my post. You are without any doubt the person who knows the most about this subject.

12-28-2020, 02:00 PM	#23
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	I would think any in lens motor from any system would fail eventually.The beauty of screw drive was always, you get a new lens motor every time you upgrade your camera body. Someday, I'll ask the guy at Sun Camera if the SDM motors fail more than one's from other systems.

12-28-2020, 02:30 PM	#24
tibbitts Pentaxian Join Date: Apr 2007 Location: Oklahoma USA Posts: 2,196	Originally posted by normhead I would think any in lens motor from any system would fail eventually.The beauty of screw drive was always, you get a new lens motor every time you upgrade your camera body. That's actually a good point. I guess there must be an engineering reason why screw drive can't be as accurate or quiet or fast, but the appeal of always getting a focus performance upgrade with every new body seems appealing. I do find it annoying that Pentax doesn't include a focus drive selection feature for those lenses with both screw drive and focus motors.

12-28-2020, 02:46 PM	#25
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,460	Originally posted by Bertrand3000 Thanks for adding, I fixed my post. You are without any doubt the person who knows the most about this subject. LOL I doubt that. I may know the most about converting the four lenses I convert - but not anything more than this.

12-28-2020, 08:24 PM	#26
pentaxus Site Supporter Join Date: Jun 2010 Location: Central Coast, CA Posts: 1,320	I have seen a few 100mm f/4 lenses with separated lens elements in the front group. Historically, when lenses used Canada balsam as cement, you might see variation in permanence with different years. I'm not sure when companies stopped using Canada Balsam.

12-29-2020, 03:01 PM	#28
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,460	Originally posted by Apet-Sure Don't forget the DA* 60-250mm SDM. Mine has failed, and apparently cannot be converted to screw-drive. That’s already listed in the post I quoted.

12-29-2020, 03:35 PM	#29
Apet-Sure Site Supporter Join Date: Dec 2015 Location: Goldsboro North Carolina Photos: Gallery \| Albums Posts: 2,872	Hmmm... I didn't see it when I read post #20, and I expected to. Oh well; mine's still dead. Manual focusing is usually not a problem when I use it, and I got it at a great price from a PF member, so I'm content.

12-29-2020, 07:28 PM	#30
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,460	Originally posted by Apet-Sure Hmmm... I didn't see it when I read post #20, and I expected to. Oh well; mine's still dead. Manual focusing is usually not a problem when I use it, and I got it at a great price from a PF member, so I'm content. I really wish it could be fixed.