50-135 SDM not working
Posted 29/04/2014 - 22:51 - Helpful Comment
Link
I think you could try turning the focus mechanism with a small screwdriver via the screwdrive slot, this seems to have worked for some people. I wonder what causes the SDM motors to fail like this?
Maybe someone can give us a technical reason.
Regards
David
Maybe someone can give us a technical reason.
Regards
David
Posted 29/04/2014 - 23:48 - Helpful Comment
Link
On Pentax Forum in the US a presumably unofficial interview with a Pentax engineer went as follows:
"Q: Our survey found that the Pentax DA* 16-50mm and 50-135mm were the most prone to SDM failure. Do you know why this was?
A: One could say that the AF components used in these lenses was prone to failure from the get-go due to their design. The 16-50mm and 50-135mm lenses share the same circuitry and motor, which is why they both have such a high failure rate. Other SDM lenses don't fail as much.
Q: Has this SDM quality control issue been resolved?
A: Yes. The components used in the 16-50mm and 50-135mm lenses have been redesigned, and all lenses produced in 2012 or later should no longer fail."
Tiny motors are used in moving the lenses and that exchange suggests that the original versions were simply not up to their allotted task over the longer term.
David's suggestion above is worth trying, and it is also worth cleaning the contacts thoroughly (that started an SDM motor of mine that I thought had failed).
It is possible to ignore the SDM motor and get the camera's screw drive to work the 50-135 but that involves altering internal settings and is probably only for the brave (or care-free). Safer, I imagine, to send the lens for repair if it can't be woken up.
"Q: Our survey found that the Pentax DA* 16-50mm and 50-135mm were the most prone to SDM failure. Do you know why this was?
A: One could say that the AF components used in these lenses was prone to failure from the get-go due to their design. The 16-50mm and 50-135mm lenses share the same circuitry and motor, which is why they both have such a high failure rate. Other SDM lenses don't fail as much.
Q: Has this SDM quality control issue been resolved?
A: Yes. The components used in the 16-50mm and 50-135mm lenses have been redesigned, and all lenses produced in 2012 or later should no longer fail."
Tiny motors are used in moving the lenses and that exchange suggests that the original versions were simply not up to their allotted task over the longer term.
David's suggestion above is worth trying, and it is also worth cleaning the contacts thoroughly (that started an SDM motor of mine that I thought had failed).
It is possible to ignore the SDM motor and get the camera's screw drive to work the 50-135 but that involves altering internal settings and is probably only for the brave (or care-free). Safer, I imagine, to send the lens for repair if it can't be woken up.
Posted 30/04/2014 - 06:53 - Helpful Comment
Link
If you have an old Pentax AF film body, give the lens a good exercise using that. Point the lens up and down while focusing, let gravity help to overcome 'stiction' problems. Finally make sure that you have a freshly charged battery in your DSLR, when you try to wake it up.
Regards Steve
Regards Steve
Posted 30/04/2014 - 13:21 - Helpful Comment
Link
If you do need a repair pay for pentax plus membership to the forum and this will give you 20% of repairs at Pentax repairers JP solutions, the repair will replace the SDM with the latest motor which should remove the failure possibility substantially.
PPG Wedding photography Flickr
Concert photography
Currently on a Pentax hiatus until an FF Pentax is released
Concert photography
Currently on a Pentax hiatus until an FF Pentax is released
Posted 30/04/2014 - 13:35 - Helpful Comment
Link
cabstar wrote:
If you do need a repair pay for pentax plus membership to the forum and this will give you 20% of repairs at Pentax repairers JP solutions, the repair will replace the SDM with the latest motor which should remove the failure possibility substantially.
It also makes it a bloody sight faster to focus
If you do need a repair pay for pentax plus membership to the forum and this will give you 20% of repairs at Pentax repairers JP solutions, the repair will replace the SDM with the latest motor which should remove the failure possibility substantially.
Posted 30/04/2014 - 13:59
Link
stevejcoe wrote:
If you have an old Pentax AF film body, give the lens a good exercise using that. Point the lens up and down while focusing, let gravity help to overcome 'stiction' problems. Finally make sure that you have a freshly charged battery in your DSLR, when you try to wake it up.
Regards Steve
I wish! Have tried that using a *istD. Up/down, panning slightly to get short sharp changes and every other way I could think. If you have an old Pentax AF film body, give the lens a good exercise using that. Point the lens up and down while focusing, let gravity help to overcome 'stiction' problems. Finally make sure that you have a freshly charged battery in your DSLR, when you try to wake it up.
Regards Steve
I am seriously thinking of a letter to Pentax saying that even out of warranty the item is "not fit for purpose" and that by redesigning the motor they must have realised there was a problem and a recall should have occurred.
Posted 30/04/2014 - 19:12 - Helpful Comment
Link
You could try "RiceHigh's Pentax Blog" link .Might be a quick cheap fix!! Or even disable SDM.
Regards, Tom
K-1ii,K-3iii's.
SMC PENTAX-F 1:2.8 28mm, HD Pentax-D FA* 1:1.4 50mm SDM AW,
SMC PENTAX-D FA MACRO 1:2.8 100mm WR,
SMC PENTAX-DA* 1:4 300mm ED [IF] SDM,
SMC PENTAX-FA* 1:4 600mm IF & ED,
HD PENTAX -DA 1.4x AW AF REAR CONVERTER,
Pentax Photo Gallery
K-1ii,K-3iii's.
SMC PENTAX-F 1:2.8 28mm, HD Pentax-D FA* 1:1.4 50mm SDM AW,
SMC PENTAX-D FA MACRO 1:2.8 100mm WR,
SMC PENTAX-DA* 1:4 300mm ED [IF] SDM,
SMC PENTAX-FA* 1:4 600mm IF & ED,
HD PENTAX -DA 1.4x AW AF REAR CONVERTER,
Pentax Photo Gallery
Posted 01/05/2014 - 14:03
Link
Thank you everybody for your comments and tips, No joy yet,
Regards Bob.
Regards Bob.
Posted 01/05/2014 - 14:36
Link
tyronet2000 wrote:
I wonder how many potential buyers have been put off by these threads regarding both the 16-50mm and the 50-135mm
Certainly has made me think about the wisdom of investing in these lenses.
I wonder how many potential buyers have been put off by these threads regarding both the 16-50mm and the 50-135mm
Posted 01/05/2014 - 14:39
Link
tyronet2000 wrote:
I wonder how many potential buyers have been put off by these threads regarding both the 16-50mm and the 50-135mm
As far as I'm concerned you can add the Pentax 17-70 to that list
I wonder how many potential buyers have been put off by these threads regarding both the 16-50mm and the 50-135mm
Barrie - Too Old To Die Young
https://pentaxphotogallery.com/artists/barrieforbes
https://www.flickr.com/photos/189482630@N03/
https://pentaxphotogallery.com/artists/barrieforbes
https://www.flickr.com/photos/189482630@N03/
Posted 01/05/2014 - 14:45
Link
Mi 16-50 also needed to be woke up before use by just refocusing it for a few times manually while attached to the camera.
Try it you never know.
Try it you never know.
Posted 01/05/2014 - 14:56
Link
Marselus wrote:
Mi 16-50 also needed to be woke up before use by just refocusing it for a few times manually while attached to the camera.
Try it you never know.
It still does Mi 16-50 also needed to be woke up before use by just refocusing it for a few times manually while attached to the camera.
Try it you never know.
With the K5ii and the K3 and quick trip in to LV and using the back AF buttom seems to wake it up, might be worth a try with the 50-135.
Cheers
Brian.
LBA is good for you, a Lens a day helps you work, rest and play.
Brian.
LBA is good for you, a Lens a day helps you work, rest and play.
Posted 29/11/2016 - 23:24
Link
CMW wrote:
On Pentax Forum in the US a presumably unofficial interview with a Pentax engineer went as follows:
"Q: Our survey found that the Pentax DA* 16-50mm and 50-135mm were the most prone to SDM failure. Do you know why this was?
A: One could say that the AF components used in these lenses was prone to failure from the get-go due to their design. The 16-50mm and 50-135mm lenses share the same circuitry and motor, which is why they both have such a high failure rate. Other SDM lenses don't fail as much.
Q: Has this SDM quality control issue been resolved?
A: Yes. The components used in the 16-50mm and 50-135mm lenses have been redesigned, and all lenses produced in 2012 or later should no longer fail."
Tiny motors are used in moving the lenses and that exchange suggests that the original versions were simply not up to their allotted task over the longer term.
David's suggestion above is worth trying, and it is also worth cleaning the contacts thoroughly (that started an SDM motor of mine that I thought had failed).
It is possible to ignore the SDM motor and get the camera's screw drive to work the 50-135 but that involves altering internal settings and is probably only for the brave (or care-free). Safer, I imagine, to send the lens for repair if it can't be woken up.
Sorry to resurrect an old thread but is this the case still with the 50-135mm? Post 2012 lenses are modified so don't have this issue??On Pentax Forum in the US a presumably unofficial interview with a Pentax engineer went as follows:
"Q: Our survey found that the Pentax DA* 16-50mm and 50-135mm were the most prone to SDM failure. Do you know why this was?
A: One could say that the AF components used in these lenses was prone to failure from the get-go due to their design. The 16-50mm and 50-135mm lenses share the same circuitry and motor, which is why they both have such a high failure rate. Other SDM lenses don't fail as much.
Q: Has this SDM quality control issue been resolved?
A: Yes. The components used in the 16-50mm and 50-135mm lenses have been redesigned, and all lenses produced in 2012 or later should no longer fail."
Tiny motors are used in moving the lenses and that exchange suggests that the original versions were simply not up to their allotted task over the longer term.
David's suggestion above is worth trying, and it is also worth cleaning the contacts thoroughly (that started an SDM motor of mine that I thought had failed).
It is possible to ignore the SDM motor and get the camera's screw drive to work the 50-135 but that involves altering internal settings and is probably only for the brave (or care-free). Safer, I imagine, to send the lens for repair if it can't be woken up.
If so, is there a serial number list so you can check the manufacturer date of the lens?
Gareth Williams ARPS
My outfit: K1ii - Pentax D FA 24-70mm f2.8 - Pentax DA* 300mm f4 - Pentax modified DA* 60-250mm f4 - Irix 15mm Firefly - Pentax FA 35mm - FA 50mm f1.4 - Tamron SP 90mm macro - Pentax AF 540 FGZ II
Welsh Photographer
Flickr
Instagram
My PPG
Foundation NFT
My outfit: K1ii - Pentax D FA 24-70mm f2.8 - Pentax DA* 300mm f4 - Pentax modified DA* 60-250mm f4 - Irix 15mm Firefly - Pentax FA 35mm - FA 50mm f1.4 - Tamron SP 90mm macro - Pentax AF 540 FGZ II
Welsh Photographer
Flickr
My PPG
Foundation NFT
Add Comment
To leave a comment - Log in to Pentax User or create a new account.
31 posts
12 years
Plymouth Devon