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Pentax Engineer on SDM Failure and Pentax DC

A brief conversation answers all our questions · Posted on 09-17-2012 in Photokina 2012
Pentax Engineer on SDM Failure and Pentax DC

Today was press day at Photokina, meaning that we were able to take a tour of Koelnmesse and see many of the exhibition halls that will officially open tomorrow.  We be making a post and uploading videos from this tour later today, so stay tuned!

Once the tour started, we of course proceeded almost immediately to the Pentax booth, which, unlike many other exhibitions, was practically ready to go and fully manned.  There, we had a conversation with a very friendly German Pentax engineer and repair technician.  He seemed to know a lot about the hardware found in Pentax lenses, so we asked him a few questions and also shared our findings from the SDM failure survey.

Below are the questions and answers, all paraphrased from the conversation.

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 redesiged, and all lenses produced in 2012 or later should no longer fail.

Q: Why is the DC technology found in the DA 18-135mm so realiable?

A: The DC motor found in the lens is based on the motors used for screwdrive autofocus in Pentax camera bodies, although it's obviously been modified to be quieter and to fit inside the lens.

So, there you have it- we have finally learned more about the technical side of Pentax SDM and DC focusing technologies!

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closhlab [Delete] Dec 6th, 2012 2:10AM

Is anyone responding to those questions? I'm curious to know when my lens was produced.

Dr. Evil [Delete] Oct 14th, 2012 2:39PM

Well, what shall I do, when my pre-2012 SDM finally fail? Take ~200 USD and send the lens to service, to replace the part, which is officially signed as defective? It seems unfair, doesn't it?

GSiGuy [Delete] Sep 20th, 2012 4:35AM

How would you know if th lens is manufactured on or after 2012?

BB_Zone28 [Delete] Sep 19th, 2012 12:13PM

No mention of the DA 17-70mm. Mine failed in just over a year's time... now it's only a manual focus lens... kind of pricey lens for such early failure and just beyond warranty. I hope they recall these lenses also.

ogl [Delete] Sep 18th, 2012 8:12AM

what are the serial numbers of DA*16-50 and 50-135 of 2012 year?

Tord [Delete] Sep 18th, 2012 2:10AM

My wife's 50-135 died not that long ago, and there was no offer from Pentax to repair it for free. As jackassp writes 'Disgraceful performance by a once respected company...'

jackassp [Delete] Sep 17th, 2012 7:32PM

I think I can hear the words "class action" echoing in the distance....

Disgraceful performance by a once respected company...

LOL LOL LOL I'm looking at the bottom of this web page and I can see a Nikon advert. This must be an omen!

wlachan [Delete] Sep 17th, 2012 6:28PM

- Whether SDM has actually been redesigned and trouble free since 2012 are still too early to tell for consumers. Without someone actually showing how they differ, I would take his words with a grain of salt.
- Even if what he said is true, the fix has come too late and too costly with yet another price hike. This is especially hurting when C/N lowend FF DSLRs start to penetrate the APS-C markets.
- Still, optical misalignment remains an ongoing issue for all Pentax lenses even the LIMITED, and loose screws on LIMITED lenses too.

bkpix [Delete] Sep 17th, 2012 4:18PM

This is very interesting. I already emailed Pentax USA asking them to fix my 16-50 and 50-135 lenses for free.

bossa [Delete] Sep 17th, 2012 4:01PM

My DA*55 and DA*50-135 are both in Japan on extended holiday (2 months and counting) and I am wondering if I will get the new components in the 50-135 at least.

offertonhatter [Delete] Sep 17th, 2012 3:49PM

I wonder if they will retro fit the new parts on existing lenses, or is that just wishful thinking?

GoremanX [Delete] Sep 17th, 2012 3:36PM

HAH! Vindicated!

London Rob [Delete] Sep 17th, 2012 3:16PM

It may have been mentioned already but in the UK (and wider Europe I think) a warranty supplied at the point of purchase is normally a no quibble repair or replacement for 12 months. However, in addition to this the customer has up to SIX years to request this service if a fault can be traced back to a design issue, poor materials or if there's sufficient evidence that the goods were not of merchantable quality across a production run. That interview would be more than enough to get a free repair over here.

rparmar [Delete] Sep 17th, 2012 2:51PM

CONCLUSION: Pentax simply has no idea how to serve their customers. Anyone who cares about their expensive goods failing had better buy some other brand.

Peter Zack [Delete] Sep 17th, 2012 2:07PM

3 years+ to do something about this issue....speechless.

Docrwm [Delete] Sep 17th, 2012 2:01PM

Thanks. Nice to know that a redesign has taken place, which means it WAS broken in the first place!

pete-tarmigan [Delete] Sep 17th, 2012 1:26PM

To reiterate DanDriedger's question, will broken lenses be repaired with the redesigned components or components of the original design?

kwaller [Delete] Sep 17th, 2012 1:22PM

I wonder when the'improved parts' were available for use in service repair? My 16-50 was repaired by CRIS before 2012.
Also what exactly is the issue with the 'prone to failure' parts?

sjwaldron [Delete] Sep 17th, 2012 1:07PM

I hope the guy doesn't get fired over that statement.

elle.e [Delete] Sep 17th, 2012 12:58PM

A pity for all those people who are past warranty period.
Or is there a "coulance"?

Blue [Delete] Sep 17th, 2012 12:45PM

I give Mr. Petersen a lot of credit for answering the question.

tlwyse [Delete] Sep 17th, 2012 12:39PM

I like "Alizarine" 's suggestion:

"I do hope they'd address a firmware update for pre-2012 models so that users can select AF mode to "screwdrive" in case their SDM breaks down
issue a free / discounted upgrade for the SDM motors"

That seems to be the most sensible.


Raffwal [Delete] Sep 17th, 2012 12:00PM

Three comments:

- Hopefully Mr. Petersen will not get problems for being this honest!
- How many times have the fanboys on this forum told last year and before that how this problem has been solved long ago!
- I wonder if the redesigned part is something that can and will be changed at the service or are the older lenses prone to problems forever?

pixivixio [Delete] Sep 17th, 2012 11:35AM

Each reliable manufacturer eliminate serial defects (what massive failure as this is) for free, unfortunately Pentax is not among them. On the contrary, they are trying to make money of their loyal customers who cuts them bread. Cost to repair my 16 50 exceeded the price of a new 40mm xs.I would ask Jens Petersen, why they did not eliminate errors immediately, but they sold out some 1.000, 10.000,.... defective lenses?

starbase218 [Delete] Sep 17th, 2012 11:05AM

So now that the word is out that they apparently put components in that were prone to fail, the question rises: what are they going to do to restore consumer confidence in their products?

krebsy97 [Delete] Sep 17th, 2012 10:58AM

The best thing Pentax can do is extend the warranties as a goodwill effort for all lenses sold. They certainly aren't going to fix copies that aren't broken (yet). Adam, nice effort here. Too bad the guy was vague. I wonder which parts have been upgraded?

MrPetkus [Delete] Sep 17th, 2012 10:49AM

I agree with all comments calling for free repair and replacement of faulty components with 2012 technology. It also looks like Mr. Peterson has probably stepped outside the Pentax script here.

zeitlos [Delete] Sep 17th, 2012 10:48AM

I couldn't agree more:

"RonHendriks1966 Sep 17th, 2012 7:52AM
Well this is good news to start with.

Maybe Adam could ask if there is a policy about repairs from older lenses?"

please support this comment!

krebsy97 [Delete] Sep 17th, 2012 10:36AM

Mr. Peterson opened up a can of worms.

elho_cid [Delete] Sep 17th, 2012 10:33AM

I had my DA*16-50 in service recently to tune the AF - the lens set on wide angle was not able to focus on infinity (or very distant subjects). The repair took a bit longer than expected and I was told that they found a problem in the SDM drive and they are exchanging the whole SDM.
I thought it was a specific problem with my SDM, but maybe they addressed the general issue and replaced it with the new failure-prone SDM as a preventive action.
OK, I'm just wishing they did.

clem [Delete] Sep 17th, 2012 10:26AM

I have the 50-135 and it has been a great lens, no sdm issues. I guess I could worry about when it will fail but would rather shoot photos and leave the blame for attorneys to work out. If I had to send it in to "fix" it, how long would I have to wait to get it back? Would I trust them again?

JoostW [Delete] Sep 17th, 2012 10:26AM

Time for a recall.

regor [Delete] Sep 17th, 2012 10:24AM

Given that it's a known design issue, the repair should be free.

DeadJohn [Delete] Sep 17th, 2012 10:05AM

It's great to see such an honest answer "The 16-50mm and 50-135mm lenses share the same circuitry and motor, which is why they both have such a high failure rate" free of corporate doublespeak. I hope Mr. Petersen's career at Pentax doesn't suffer for it.

bobell69 [Delete] Sep 17th, 2012 9:52AM

If there is a class action it should be directed to Hoya then and not to Ricoh Pentax since Pentax was in their corporate holdings at the time, but then again when you buy the business you buy the problems that come along with it.

JeremytheIndian [Delete] Sep 17th, 2012 9:52AM

@Adam Thanks a ton! I just saw your forum post about calling in... Still on the fence between Tammy 70-200 or the 50-135 but you've helped me a ton (in making my decision harder) :)

bobell69 [Delete] Sep 17th, 2012 9:27AM

So from his comments "The components used in the 16-50mm and 50-135mm lenses have been redesiged, and all lenses produced in 2012 or later should no longer fail" indicates to me that Hoya never did address the problem and allowed the SDM issue to continue and it wasn't until Ricoh took over that the issue has actually been addressed. Hoya's ethical practises are sure suspect here then.

slackerlee [Delete] Sep 17th, 2012 9:20AM

thanks for the reply, just added my # to the data base, so far the highest for whatever that is worth. But I bought it in March of 2012 so unless B&H got it with no lag time from the factory i'm out of luck I think.
If it breaks, one might be able to use the comment in the article to get them to fix for free or real real cheap.

Belcik [Delete] Sep 17th, 2012 9:16AM

Good. Makes me feel like buying 16-135 Lens.

Adam [Delete] Sep 17th, 2012 9:11AM

There isn't a way to check the date for sure, but you can take a look at the serial database to browse recent serial numbers.

slackerlee [Delete] Sep 17th, 2012 9:00AM

is there a way to tell the date made from the serial #.


LaurenOE [Delete] Sep 17th, 2012 8:53AM

Great question. Great answer. Well done.

Jonathan Mac [Delete] Sep 17th, 2012 8:51AM

So how are the 2012 lenses identified? If I were on the market for either of these lenses I would only accept a 2012 one.

JinDesu [Delete] Sep 17th, 2012 8:39AM

Good to hear - but a little late since I got my Sigma 50 instead of the DA*55...

Maybe I'll consider the 50-135 next year...

Not a Number [Delete] Sep 17th, 2012 8:34AM

Automobile manufacturers (at least in the US) have "hidden" warranties on components that fail due to design or manufacturing defects. They replace these parts when they fail for free - labor and parts. For instance the exhaust manifold on one of my Toyota cars was prone to cracking. It was replaced for free. I found out later the clock was covered by a similar "hidden" warranty.

Be nice if Ricoh / Pentax did the same.

DragonLord [Delete] Sep 17th, 2012 8:32AM

Finally, an honest answer!

No more worrying about SDM issues. Rejoice!

laolao [Delete] Sep 17th, 2012 8:28AM

So for new SDM, is that the reason why the price increases so much?

fun size nick [Delete] Sep 17th, 2012 8:23AM

I didn't realise that the nature of the DC focus motors was a mystery - Canon has been doing 'DC focus' for quite some time now!

Alizarine [Delete] Sep 17th, 2012 8:17AM

I do hope they'd address a firmware update for pre-2012 models so that users can select AF mode to "screwdrive" in case their SDM breaks down


issue a free / discounted upgrade for the SDM motors

Adam [Delete] Sep 17th, 2012 8:15AM

@jeremytheindian - call B&H and you can get it for $824 or thereabout. Only the online prices are crazy.

JeremytheIndian [Delete] Sep 17th, 2012 8:07AM

Well as long as the 50-135 stays at $1,524 after "rebate" I can't afford it anyways.

marq [Delete] Sep 17th, 2012 8:01AM

(I feel a class action coming up...)

DanDriedger [Delete] Sep 17th, 2012 7:59AM

I'm about to send my 50-135 back for the 2nd time. (average life expectancy before failure is 9 months) My question would be whether the "fix" that has been integrated into the new 2012 lenses is also being used to fix older lenses?

Alizarine [Delete] Sep 17th, 2012 7:58AM

ALL LENSES PRODUCED 2012 OR LATER huh... ok, I'll mark those words...

marq [Delete] Sep 17th, 2012 7:58AM

Now that the cat's out of the bag, yeah, please fix our old lenses, Pentax!

RonHendriks1966 [Delete] Sep 17th, 2012 7:52AM

Well this is good news to start with.

Maybe Adam could ask if there is a policy about repairs from older lenses?

Ameiji [Delete] Sep 17th, 2012 7:51AM

Yay! It's time to drop the prices for lenses made before 2012. I'd say, a half-price would do! :D

GabrielFFontes [Delete] Sep 17th, 2012 7:44AM

So that also explain why DC is faster...