DA* motor failure rate

I am tempted by the DA* 16-50 but obviously have come across the apparently many tales of failed motors , which based on the cost of the lens seems extraordinary.


As nothing spreads quite as fast as bad news.....does anybody know what the percentage failure rate actually is ?

Is the failure rate associated with a certain batch or era ?

if and when it goes...how much is it likely to cost to repair ?

Any help or further words of wisdom are most welcome !


Currently using K5 / standard lens and 17-70mm

I'm not sure how many years ago now the 16-50mm lens was introduced, but the problems occurred with an early batch, if not the first batch.

It's all a very long time ago and I'd buy a current lens with confidence.

If you haven't already, take a look at http://www.pentaxforums.com/forums/pentax-slr-lens-discussion/83743-sdm-silent-a... It can scarcely be called scientific; but so long as manufacturers keep failure statistics to themselves, it is impossible to know the truth of the matter .... and to stop rumours, unfounded or not, spreading. I have two lenses powered by SDM, so I'm amongst those hoping for the best. On at least one of those lenses (50-135), there is a slightly terrifying firmware 'fix' that will permit the camera's screw drive to operate the lens. It is not for the faint-hearted, but if the SDM motor were to fail, I might try it. The lens itself is extraordinarily good for a zoom.

I did think about selling the 50-135 before the SDM fails but I have concluded that it is such an outstanding lens then the repair cost is worth it. As Pentax simply haven't come clean about the problem and what they have done to overcome it then I wouldn't trust the reliability of the SDM motor. I think Pentax would have been better served by repairing those motors that clearly weren't fit for purpose given the endemic failure rates and reassuring us about what design changes they have made for buyers of the newer lenses. Sweeping issues under the carpet is rarely going to win customers over.

As I understand it there was a failure in some early motors and subsequent ones were upgraded. Online "surveys" are meaningless as only those interested take part and that ignores the vast unconcerned majority.

We haven't heard of any SDM problem for a very, very long time, have we?

Online surveys are not necessarily meaningless, though they have obvious shortcomings. The survey I referred to actually seems to indicate some healthy participation by the 'unconcerned majority'. I agree with Dr O's sentiments and that Pentax might have done itself, as well as its customers, a favour by greater openness. Anyone looking to acquire an SDM lens, immediately comes across a litany of woes about the motor on the internet, which only one source can authoritatively counter.

Frogfish kicked off the year with a report of a failed SDM, so, yes, we are still getting notifications from time to time.

The OP may find this informative, it gives a very balanced view.

According to a Pentax engineer interviewed there was a problem that was fixed with a redesign. But there has been nothing from Pentax on the issue and they have never acknowledged the problem. So maybe you and Pentax top brass are correct and there was only ever a few teething issues with early lenses or maybe the Pentax engineer was right and there was a design fault leading to hundreds of failures over a few years - the information is all there and can be interpreted as one wishes.

Personally if the SDM was redesigned in 2012 I think it is too early to conclude on its long term reliability although I agree it is encouraging that newly manufactured lenses haven't shown the same problem yet. I'd personally conclude that there is much less risk in buying a newer lens but a high risk associated with an older one. I don't know when the exact cut-off point might be or how you would go about checking when a lens was manufactured.

I would have thought that a Pentax engineer saying something qualified as Pentax saying something? Can we separate the two?

Anyway, we have the answer, so many thanks for that.

Yes we can. It's called whistleblowing and it isn't very popular amongst employers. Corporate announcements on product faults are very carefully controlled to protect a company from additional expenses and litigation. The normal consequence of an engineer admitting a product fault would be the sack. The contract of employment carefully controls what information an employee can disclose about their employer.

If you read the articles a lot of the feedback is concern for the job security of the individual concerned. In this case I suspect it was a slip of the tongue rather than any form of officially endorsed communication channel.

As we don't know the sales figures either we will never know the percentage of faulty lenses.

both my da* lenses where bought uses and no issues with either. My 50-135 is getting on for 5 years old and in guessing its done over 50,000 clicks...

According to the article DrO the engineer was answering questions at a sales booth, not exactly whistle-blowing!

It seemed like a straight answer to a straight question to me.

2 of my 3 SDM lenses have failed

The 60-250 failed within a year of purchase and fixed on warranty - it was thought this lens was immune to the SDM problems, SRS were surprised but fixed - it's had a bit of an episode since, but fixed with a jeweller's screwdriver - lens came back better than new.

Then the 16-50 packed up, it was hesitating and then just stopped. This cost me £180 to fix. I think this had the newer motor fitted and it's been like a new lens since

In spite of this, it has not put me off Pentax lenses, until about 3 years ago I had a multitude of zoom lenses (Pentax and Sigma), the DA* are so good I have those two now, plus the Sigma 150-500.

Indeed but information he was not probably not supposed to divulge, which is why I said a slip of the tongue. I bet he won't be so forthright next time.

Imagine the amount of goodwill Pentax could have generated by admitting there was an issue, fixing affected lenses and announcing the redesign of the system to restore consumer confidence in sdm and give customers huge confidence in all products. It would have avoided the necessity of the op's question. An attitude like thay would win lifelong customers.

Thanks for the helpful opinions.

My own thoughts are that if you were the proud owner of a premium product which then failed, in all probability, you will let anyone who is willing to listen know exactly how you feel ....which I would imagine would be fairly cheesed off.

On the other hand if the product didn't fail....you may be less anxious to tell the world how good it is. I suppose I was trying to establishif if the substantial negative reports are a fair indication of the failure rate.

Logically as a manufacturer I would assume that Pentax would wish to do something to counter the negative publicity...which they may well have with the redesign ?

Other than motor issues all other reports are very positive !

I also assume that purchasing with a warranty would be wise !

Regards

Eugene