Pentax smc DA* 50-135mm SDM Issue

I'm of similar opinion to you, I don't take as read that a lens is superior because it has an OEM brand name on.

Many Sigma lens a clearly superior to their OEM brethren especially when they (Sigma) are attacking a market segment, HSM is an example of this where the technology is every bit as functional as Canons USM implementations.

Whereas SDM is IMO not technically very clever if the objective is fast silent focusing but I suspect those were not the design constraints rather suspect they wanted three way focus at all costs.

Those blinkered to OEM only are missing some of the best lens in production.

awaldram wrote:

As you asked where I got ny evidence that failure rates had normalized for SDM inc the 16-50 and 50-135.

Here are the stats form PF for 2011 (the only year with enough numbers)

percentage chance of failure worst to best

17-70 26%

16-50 23%

55 8%

300 8%

50-135 8 %

60-250 2%

200 0%

18-135 0%

I see no evidence to back up your claim on the frailties of the 16-50 and 50-135 as compared to the rest.

Could you post your evidence ?

You complain same old explanations but unless the facts change how can the conclusion?

I'm not a bif fan of Pentax's ultrasonic implementation and believe there was a lot cleaner ways to do it if you dropped backward compatibility, yet the accusations ledged against it I find unfounded and always without evidence.

For every member screaming from the rafters about their failed SDM there are 10 users quietly taking pictures with theirs.!

Demoguy wrote:

On Tuesday I went to Everett Wa. to look at a possible project. The Nimitz, CVA 68 is back from a long deployment so I thought I would stop along the waterfront and take some photos. I pulled out my camera (k-3) with the DA* 50-135 on it and lo and behold, no auto focus. I bought this lens last year on black Friday, so its three weeks out of warranty. Anyway it was @ 29 deg F so I ended up using manual focus and with my bad eyes the result was not so good. Today I mounted the lens on my K-5 and nothing happened, then on the K-01 and it woke up. Tried it on all the other cameras and it worked fine. I wonder if it was just cold or if this is a sign of SDM failure.

Has anyone had this lens fixed at CRIS recently and would you have a cost?

Thanks,

Joe

Because its a known issue of some sort I would call and ask for some good will from Pentax. In any case I believe the cost I have seen to repair, although not cheap would be made back if you ever sold it. Also considering it is a great lens you will still be ahead if you pay the repair cost (should be under $270?). You also have other no cost ways of restoring AF written above.

You may want to just send it in for a cost and state on the letter how close out of warranty it is. When you call and speak to someone they don't have the power to say, "no charge". They are office phone... When being repaired they can make it a no charge more easily. But there would be a small fee for shipping back to you if not repaired.

But again as I have written over and over. Pentax needs to get rid of this issue. It has to keep some would be Pentax buyers away from Pentax you would think. Pentax only needs to change a few lens. Why not coat the DA* lens with the HD coating, give it a bit faster motor (just a bit) and call it DA*II series of lens. Buyers would know the SDM issue is gone on those models.

Just the very fact we are even writing about it shows a demon real or not called SDM AF failure is still with Pentax.

But! I do want to make sure all know every manufacture of photo gear has at least one demon, most more. I am only trying to help Pentax and the OP.

I agree. One of the lenses in my Canon system is a Tokina AT-X 300/2.8 SD AF. A very well regarded lens by Photodo. Yes it doesn't have IS and it doesn't have USM or HSM. On the other hand it only cost me $700. Where else can you buy a sharp 300/2.8 AF lens for that price? Even the pre-IS Canon 300/2.8 lenses cost twice as much used. Heck I could have paid that much for a Tamron AD-2 300/2.8 manual lens.

Kent Gittings

jamesm007 wrote:

Demoguy wrote:

On Tuesday I went to Everett Wa. to look at a possible project. The Nimitz, CVA 68 is back from a long deployment so I thought I would stop along the waterfront and take some photos. I pulled out my camera (k-3) with the DA* 50-135 on it and lo and behold, no auto focus. I bought this lens last year on black Friday, so its three weeks out of warranty. Anyway it was @ 29 deg F so I ended up using manual focus and with my bad eyes the result was not so good. Today I mounted the lens on my K-5 and nothing happened, then on the K-01 and it woke up. Tried it on all the other cameras and it worked fine. I wonder if it was just cold or if this is a sign of SDM failure.

Has anyone had this lens fixed at CRIS recently and would you have a cost?

Thanks,

Joe

Because its a known issue of some sort I would call and ask for some good will from Pentax. In any case I believe the cost I have seen to repair, although not cheap would be made back if you ever sold it. Also considering it is a great lens you will still be ahead if you pay the repair cost (should be under $270?). You also have other no cost ways of restoring AF written above.

You may want to just send it in for a cost and state on the letter how close out of warranty it is. When you call and speak to someone they don't have the power to say, "no charge". They are office phone... When being repaired they can make it a no charge more easily. But there would be a small fee for shipping back to you if not repaired.

But again as I have written over and over. Pentax needs to get rid of this issue. It has to keep some would be Pentax buyers away from Pentax you would think. Pentax only needs to change a few lens. Why not coat the DA* lens with the HD coating, give it a bit faster motor (just a bit) and call it DA*II series of lens. Buyers would know the SDM issue is gone on those models.

Just the very fact we are even writing about it shows a demon real or not called SDM AF failure is still with Pentax.

Very astute observation James. My 50-135 failed some months back (AF as dead as the extinct Dodo) and I have just dropped it off at the hospital over the holidays. That lens would barely have been on my cameras for more than 100 shots. To all intents and purposes brand new. I've also heard the cost to repair this SDM failure can be as much as $300 or more, yes? It makes it a very expensive lens instead of just an expensive lens - around $1200 new plus $300 for repairs? A hidden cost is also that because of the reluctance of people to buy used SDM lenses, their resale value is less than it should be.

On a related topic, I know there is a method linked to on other forums to convert a lens from SDM to screw drive. I have read and reread these instructions but find some of the steps difficult to follow and understand. Has anyone who has successfully interpreted the instructions re-written them in a clearer way?

"On a related topic, I know there is a method linked to on other forums to convert a lens from SDM to screw drive. I have read and reread these instructions but find some of the steps difficult to follow and understand. Has anyone who has successfully interpreted the instructions re-written them in a clearer way?"

I would strongly advice all non hard core computer programmers or engineers to not(!) try the method at Pentax Foru... its wiping out parts of your cameras firmware and re-writing it with other values. Even backing it up is a dangerous procedure.

The number one rule is to follow directions to the letter. But if your not 100% sure, positive, just don't do it.

I just read the way its done. I thought the method was to cover lens contact pins. That's one thing. To reprogram your firmware in a fashion as this is dangerous. Do you know why the directions say use notepad and not Microsoft word? If not just don't do it. You can use other text editors. But only certain ones, why? If you don't know why don't do it.

I feel for those with SDM that don't work. Go back and read my posts when I went to the store before SDM was an issue and the DA*50-135mm auto-focus would not work at the camera shop! The lens had been sitting on the shelf for a long time. I tried it, was going to get it and then everyone's DA*50-135mm lens (a lot) started to act up all around the same period of time. Its all written down.

-Hi,

The whole SDM story is a veiled and disappointing one, firstly, OK, any manufacturer can design a system which turns out over a period of time to be "unreliable" , normally the follow on is a redesign which cures the problem and this is what happened eventually, only many years went by before they addressed themselves to the problem. These lenses are batch produced and many thousands were manufactured and stocked for sale appropriately.

What to do with these lenses after it became apparent that in fact there was a problem with the SDM system? Take them out of the warehouse and rebuild them with the new replacement motor? No, that would have cost a fortune and would have resulted in a tremendous financial loss, what to do then? Answer nothing at all, admit to a problem? well not out loud.

So they decided to say "nothing" (excepting an unofficial mutter at I think, Photokina ) knowing that the majority of the lenses would likely at least last out the one years guarantee (although many didn't) and thereafter have the customer pay for the repair. So from having a potential situation of facing a complete motor change of all their SDM lens stock and all the losses that would entail they stood back and let the customer pay.

What is the situation now?  Well the new motors are there, but there's still plenty of the old motor stock about for sale and Pentax hasn't released any serial numbers to indicate the changes, so you buy in the dark.

I thin your seeing 2+2 and making 5

your theorem is based on SDM lasting the 12 months warranty period .!

Yet in 90% of the world Pentax lens come with 2 years warranty and on top of that through most of Europe will have a consumer protection for design failure in the 6 year region.

So why would Pentax keep quite on a ticking bomb when in most of the world it is themselves who will foot the bill and get hit with bad publicity to boot.?

On your 'new motors' again I see no evidence accept from the same discredited third party source in Germany.

I would consider it a lot more likely that failures are not that great and though earlier ones are more likely to fail (probably due to manufacturing tolerances) Pentax decided that FoF (Fix on Fail) was cost effective for all units sold.

My 50-135 was replaced by Pentax UK after 4 year free of charge and the motor is identical to the original, the revision status of  the Motherboard was newer but I can't remember now what its markings were.

So we have

2008 purchased 50-135

2010 first reports about new motors

2012 2nd rumour about new motors reported

late 2012 50-135 replaced directly by Pentax UK (not repairers) motor is identical unit as 2008 original.

The 50-135 I received was not a new unit but a factory refurb being the unit all UK reviews are based on (i.e demo stock) so would have all mec releases fitted.

I have a 50-135 that will be 3 years old. It's been used in snow blizzards and temperatures down to -20 (if not less). It's still working although focusing is as slow as it ever was.

jamesm007 wrote:

"On a related topic, I know there is a method linked to on other forums to convert a lens from SDM to screw drive. I have read and reread these instructions but find some of the steps difficult to follow and understand. Has anyone who has successfully interpreted the instructions re-written them in a clearer way?"

I would strongly advice all non hard core computer programmers or engineers to not(!) try the method at Pentax Foru... its wiping out parts of your cameras firmware and re-writing it with other values. Even backing it up is a dangerous procedure.

The number one rule is to follow directions to the letter. But if your not 100% sure, positive, just don't do it.

I just read the way its done. I thought the method was to cover lens contact pins. That's one thing. To reprogram your firmware in a fashion as this is dangerous. Do you know why the directions say use notepad and not Microsoft word? If not just don't do it. You can use other text editors. But only certain ones, why? If you don't know why don't do it.

I feel for those with SDM that don't work. Go back and read my posts when I went to the store before SDM was an issue and the DA*50-135mm auto-focus would not work at the camera shop! The lens had been sitting on the shelf for a long time. I tried it, was going to get it and then everyone's DA*50-135mm lens (a lot) started to act up all around the same period of time. Its all written down.

Its time Ricoh consider putting the option in the camera firmware for activating the screw drive if the SDM fails. Its so weird that they install the screw drive together with the SDM for the DA* lenses but do not allow it to be used. Its like paying for something but can't use it. Simply does not make any sense.

It would be a very useful option.

Bonn wrote:

jamesm007 wrote:

"On a related topic, I know there is a method linked to on other forums to convert a lens from SDM to screw drive. I have read and reread these instructions but find some of the steps difficult to follow and understand. Has anyone who has successfully interpreted the instructions re-written them in a clearer way?"

I would strongly advice all non hard core computer programmers or engineers to not(!) try the method at Pentax Foru... its wiping out parts of your cameras firmware and re-writing it with other values. Even backing it up is a dangerous procedure.

The number one rule is to follow directions to the letter. But if your not 100% sure, positive, just don't do it.

I just read the way its done. I thought the method was to cover lens contact pins. That's one thing. To reprogram your firmware in a fashion as this is dangerous. Do you know why the directions say use notepad and not Microsoft word? If not just don't do it. You can use other text editors. But only certain ones, why? If you don't know why don't do it.

I feel for those with SDM that don't work. Go back and read my posts when I went to the store before SDM was an issue and the DA*50-135mm auto-focus would not work at the camera shop! The lens had been sitting on the shelf for a long time. I tried it, was going to get it and then everyone's DA*50-135mm lens (a lot) started to act up all around the same period of time. Its all written down.

Its time Ricoh consider putting the option in the camera firmware for activating the screw drive if the SDM fails. Its so weird that they install the screw drive together with the SDM for the DA* lenses but do not allow it to be used. Its like paying for something but can't use it. Simply does not make any sense.

From a Japanese viewpoint it makes perfect sense.

Whereas you or I may see addition of a screw option a choice and hence a good thing, I think Pentax see it as an admition of failure and given Japanese culture will never happen.

I would have released it as a cost option and use PR to dress it up 'We don't want our users reverting to screw but understand there is a wish amongst some of our customers we therefore release a custom firmware at £xx to cater to their wishes. (Whilst 3 way lens are in production)"