SDM question submitted to Ned Bunnell's blog

What he says is that there is evidence of failures for motorized lenses made by other manufacturers than Pentax. There is an idea in this forum that the other makers has no failures because they have longer experience with in-lens AF technology than Pentax.
So he shows evidence about other makers has in-lens AF failures too.

The evidence that Canon has failures here may come as a surprise for some here that supports the idea of Canon having no failures because they have long experience with the technology. Obviously "long experience" is not a valid parameter.

To sum up - he simply states that "grass is not greener on the other side" and if you think this is "nonsense", to use your own wording here, then please think so.
I wish you happiness with your PBS. (personal belief system).

--
Take care
Raphael
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Model Mike said:

bkpix said:

The few actual statistics that are available -- and I don't mean self-selecting polls on the web -- actually tend to contradict the idea that there is anything remarkable about the SDM failure rate.

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Sorry o/p, but I've rarely read such a load of unsubstantiated and misleading nonsense.

Your central claim is that there is no evidence that SDM is any less reliable than other lenses. You may be right but there is absolutely nothing in your post which supports this claim.

Model Mike said:

The numbers posted at lensplay {dot} com

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Well you clearly didn't even read the first line of their home page:

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Your killing me raflmao

Model Mike said:

This section of LensPlay deals with technical issues related to camera lenses. Currently it is focused on lenses for the Canon EOS system, but in the future it may expand to lenses for other cameras.

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Der.......

Model Mike said:

There's not a single Pentax lens listed on their lens list. And nobody's ever heard of this site anyway.

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Love it you haven't heard of one of the premier lens resources on the net ....stop it I'll split my sides.

Model Mike said:

But given that you seem to have X-ray eyes, which figures are you talking about?

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Oh to save your blushes

http://www.lensplay.com/lenses/lens_defect_results.php

Model Mike said:

Model Mike said:

Also check out, for example, the lens repair stats at lensrentals {dot} com, where zoom lenses from other manufacturers (they don't stock Pentax) have annual failure rates of 10 to 40 percent.

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Lol. They 'don't stock Pentax! So what is the relevance of this statement?

Model Mike said:

The fact is that digital photo gear generally fails at a much higher rate than the mechanical cameras of yesteryear, which were a much more mature technology.

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Agreed. But irrelevant.

Model Mike said:

Also weighing against the idea that Pentax SDM is especially prone to failure is the company's reasonably quick response to the K-5 stained sensor fiasco. This leads me to believe that the company would react similarly if they had an actual measurable problem with SDM.

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Well that's a bizarre conclusion. It's like saying that because Toyota is quick at servicing your car, they couldn't ever be the subject of a recall.

Model Mike said:

And, yes, I own the 16-50 and 50-135.

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Clearly, ownership has done nothing for your powers of deduction.

Completely worthless post.

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I think your making a fool of yourself, If your going to trash someone points it generally a good idea todo some research.

Model Mike said:

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Raphael Mabo said:

So he shows evidence about other makers has in-lens AF failures too.

The evidence that Canon has failures here may come as a surprise for some here that supports the idea of Canon having no failures because they have long experience with the technology. Obviously "long experience" is not a valid parameter.

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or not said. People are aware C/N have their share of lens motor failure as well. The problem is the ongoing SDM ordeal which Pentax have made no public acknowledgment of. The idea that SDM failure only affected the early batch is unfounded as new failures keep popping up in different forums. When a lens being repaired 3 times and still died, or the SDM died just by sitting around. Something is very wrong.
--
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awaldram said:

awaldram said:

There's not a single Pentax lens listed on their lens list. And nobody's ever heard of this site anyway.

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Love it you haven't heard of one of the premier lens resources on the net ....stop it I'll split my sides.

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Yep. Never heard of them. Guilty as charged.

awaldram said:

Oh to save your blushes
http://www.lensplay.com/lenses/lens_defect_results.php

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Thank you for the link. I quote: "The bottom line is therefore that these numbers should be treated with some skepicism"

He listed five reasons for caution.

No attempt has been made to weight the figures according to the popularity of each brand, and when you consider that Pentax and Nikon garnered roughly the same number of faults, it doesn't look so good for Pentax.

awaldram said:

I think your making a fool of yourself, If your going to trash someone points it generally a good idea todo some research.

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Thanks, I think you've done the research for me.
--
Mike
http://flickr.com/rc-soar

Model Mike said:

No attempt has been made to weight the figures according to the popularity of each brand, and when you consider that Pentax and Nikon garnered roughly the same number of faults, it doesn't look so good for Pentax.

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I take this statement back - I failed to look further down the page. My bad, my apologies.

Nevertheless caution is still warranted because the figures apply to manufacturers' complete ranges, not to sub-sets of their range (like SDM).
--
Mike
http://flickr.com/rc-soar

Model Mike said:

I take this statement back - I failed to look further down the page. My bad, my apologies.

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Whoops... it seems I apologised too soon.

The Lens Defect survey is based on reports of 'dead on arrival'. Which means that it's largely irrelevant to the discussion regarding SDM failures, since these typically occur after the lenses have had some use. I quote:

This is a survey intended to try to look at the quality control (QC) of lenses. What we need to know is how many new lenses that you received in the last 5 years were defective when they arrived. Note this isn't a survey related to how many lenses have broken during use - that's another issue.

http://www.lensplay.com/lenses/lens_defects2.php

--
Mike
http://flickr.com/rc-soar

Model Mike said:

Model Mike said:

No attempt has been made to weight the figures according to the popularity of each brand, and when you consider that Pentax and Nikon garnered roughly the same number of faults, it doesn't look so good for Pentax.

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I take this statement back - I failed to look further down the page. My bad.

Nevertheless caution is still warranted because the figures apply to manufacturers' complete ranges, not to individual lenses.

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Yet individual reports of multiple failures from people who's honesty and sincerity are a complete unknown should be taken as gospel and publicised as much as possible always referred to as fact and if anybody dares to question the lynch mob they will be subject to ridicule and abuse.

Every attempt should be made to make Penatx pay for smiting these unknown people with their badly designed products.

So without any concrete of evidence Pentax SDM is condemned, Seems like a lynch mob mentality to me.

As I say makes no odds to me I'll carry on using my lens as I see fit and go on my own concrete evidence that SDM is at least as reliable as any other Ultrasonic solution out there.

Where I do have sympathy is the ludicrous warranty situation in the US for prime quality lens 12 months is shall we say taking the pxss.

If you want to get a feel for how much hysteria is wipped up re Pentax failure then take a look at failure rate for to popular Sony lens

Sony 24-70 f/2.8 ZA
Sony 70-200 f/2.8 APO

Both have above 30% failure rate now look on the sony forum to see how much moaning about their abysmal record.
That right none.

So is Pentax failure rates massively higher then this.?

To generate the level of response I see only two possibilities

1 Pentax SDM is a real crock with 50-60% failure rate
2 Internet hysteria is out of control people comment with no experience at all.

Now if its 1 then I'm really bucking the odds and I need to buy a lottery ticket quickly as I should have experienced at least 2 failures by now.

Model Mike said:

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wlachan said:

Raphael Mabo said:

So he shows evidence about other makers has in-lens AF failures too.

The evidence that Canon has failures here may come as a surprise for some here that supports the idea of Canon having no failures because they have long experience with the technology. Obviously "long experience" is not a valid parameter.

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or not said. People are aware C/N have their share of lens motor failure as well. The problem is the ongoing SDM ordeal which Pentax have made no public acknowledgment of. The idea that SDM failure only affected the early batch is unfounded as new failures keep popping up in different forums. When a lens being repaired 3 times and still died, or the SDM died just by sitting around. Something is very wrong.

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Again how many of your lens have failed 3 times or are you just re-canting rumour and promoting the background noise. ?

How many of your lens have died just sitting around.

I do agree something is very wrong but I'm not convinced its SDM

What is it you want Pentax to publicly acknowledge .??

Member said:

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awaldram said:

...

Where I do have sympathy is the ludicrous warranty situation in the US for prime quality lens 12 months is shall we say taking the pxss.

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I just checked the Canon USA website. They also offer only a one year warranty on their lenses! That surprised me, given the longer warranties offered by Tamron and Sigma.

Are Pentax SDM lenses more prone to failure than Canon or Nikon lenses? I don't think we have enough evidence to know. What is clear is that they have a reputation for early failure, whether deserved or not. It is unusual for a company to let something like this fester for years the way Pentax has.

--
Jeff

My cat, who likes to sprawl on my keyboard, is responsible for all typos, misspellings, factual errors, and faulty logic in my posts.

Don't think it make sense to bash pentax for giving 1 year warantee, thats more or less the industry standard. Only Camera Manufacturer which I know gives more than 1 year warantee on lenses is Nikon. All Nikon lenses have 5 yr US warantee.

Jeff Charles said:

awaldram said:

...

Where I do have sympathy is the ludicrous warranty situation in the US for prime quality lens 12 months is shall we say taking the pxss.

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I just checked the Canon USA website. They also offer only a one year warranty on their lenses! That surprised me, given the longer warranties offered by Tamron and Sigma.

Are Pentax SDM lenses more prone to failure than Canon or Nikon lenses? I don't think we have enough evidence to know. What is clear is that they have a reputation for early failure, whether deserved or not. It is unusual for a company to let something like this fester for years the way Pentax has.

--
Jeff

My cat, who likes to sprawl on my keyboard, is responsible for all typos, misspellings, factual errors, and faulty logic in my posts.

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--
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One follow-up note. A participant in another forum yesterday posted this email response fro a Pentax rep about the SDM issue:

Thank you for contacting Pentax.

PENTAX Imaging Company in the US has analyzed our sales and repair data. This
information shows us that the warranty repair rate on all SDM lenses is at, or
in most cases well below our normal return rate. Additionally, this takes into
account all types of warranty repair. If we analyzed only repairs related to
SDM failure, the repair rate would be well below our average, indicating there
is not an issue with this system.

If you are in need of further assistance, please respond to this email or call
our technical support center at 800-877-0155.

Sincerely,
Randall S.
Pentax Imaging Technical Support

Pentax is the only place that has all the data on any SDM problems, which means you can either believe them or not. In the absence of any credible evidence to the contrary, I'm inclined to take them at their word.

Admittedly "Randall S.," who doesn't even seem to have a last name, isn't very high up the corporate food chain. But he does seem to speak with authority.

I am sympathetic to the worries of people who see the endless web posts and polls and so on about SDM. I would suggest, though, spending some time researching the issue of self selection bias.

You might even start with Wikipedia, which has a very brief article on the topic that notes: "Self-selection bias is a major problem in research in sociology, psychology, economics and many other social sciences.... Self-selection makes it difficult to determine causation."

Also read up on confirmation bias, the natural human tendency to see only evidence that supports our beliefs.

Thanks for finding this and posting it. For me, it is just what we need to hear from Pentax, since as you wrote, only they know the true SDM repair statistics. Like you, I am inclined to believe what Randall S. wrote. It is a straight forward statement that does not sound like marketing spin. An official statement from Pentax would be better, of course, but this is a step in the right direction.

--
Jeff

My cat, who likes to sprawl on my keyboard, is responsible for all typos, misspellings, factual errors, and faulty logic in my posts.

Jeff Charles said:

Thanks for finding this and posting it. For me, it is just what we need to hear from Pentax, since as you wrote, only they know the true SDM repair statistics. Like you, I am inclined to believe what Randall S. wrote. It is a straight forward statement that does not sound like marketing spin. An official statement from Pentax would be better, of course, but this is a step in the right direction.

--
Jeff

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A formal statement is going to have a lot of marketing fluff attached. If you're worried about marketing double speak, an official statement is hardly going to reassure you.

bkpix said:

One follow-up note. A participant in another forum yesterday posted this email response fro a Pentax rep about the SDM issue:

Thank you for contacting Pentax.

PENTAX Imaging Company in the US has analyzed our sales and repair data. This
information shows us that the warranty repair rate on all SDM lenses is at, or
in most cases well below our normal return rate. Additionally, this takes into
account all types of warranty repair. If we analyzed only repairs related to
SDM failure, the repair rate would be well below our average, indicating there
is not an issue with this system.

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Well hello, failing in the warranty period isn't exactly what the issue is, is it?

Thank you
Russell

--
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The key words here are "the warranty repair rate on all SDM lenses". Warranty is only 1 year in the US (2 years in the EU). So, it means nothing to the users whose SDM lenses have failed after the (very short) warranty period. I don't think that it is reasonable to pay 1000 USD or more for a DA* lens, cross your fingers and hope that its SDM motor won't break after a a year or two of use. The rest of the letter is the usual marketing nonsense.

Carlos

Randall's statement is copy and pasted, he sent me the identical thing which I posted in the other forum a few weeks ago.

Philip Goh said:

Jeff Charles said:

Thanks for finding this and posting it. For me, it is just what we need to hear from Pentax, since as you wrote, only they know the true SDM repair statistics. Like you, I am inclined to believe what Randall S. wrote. It is a straight forward statement that does not sound like marketing spin. An official statement from Pentax would be better, of course, but this is a step in the right direction.

--
Jeff

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A formal statement is going to have a lot of marketing fluff attached. If you're worried about marketing double speak, an official statement is hardly going to reassure you.

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You are probably right.

Even a post here from Ned restating what Randall S. wrote would be good. IAC, the Randall S statement and the feedback I got a while ago from Camera Lens Rentals have helped to clear up some of the uncertainty about SDM for me.
--
Jeff

My cat, who likes to sprawl on my keyboard, is responsible for all typos, misspellings, factual errors, and faulty logic in my posts.

Jeff Charles said:

awaldram said:

...

Where I do have sympathy is the ludicrous warranty situation in the US for prime quality lens 12 months is shall we say taking the pxss.

Click to expand...

I just checked the Canon USA website. They also offer only a one year warranty on their lenses! That surprised me, given the longer warranties offered by Tamron and Sigma.

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Tamron and Sigma are exceptions to the norm, most likely because they need to provide photographers with an incentive to buy their lenses. I've had a very poor experience with Sigma lenses over the years (mostly front focusing lenses that are claimed to be "as designed") and will definitely not be buying their lenses unless there is no alternative.

Never had a problem with Pentax lenses though, and I own the 16-50 and 50-135 for over a year now.

Jeff Charles said:

awaldram said:

...

Where I do have sympathy is the ludicrous warranty situation in the US for prime quality lens 12 months is shall we say taking the pxss.

Click to expand...

I just checked the Canon USA website. They also offer only a one year warranty on their lenses! That surprised me, given the longer warranties offered by Tamron and Sigma.

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The company with the crappier product always has to offer a longer warranty, or nobody will buy it at all. That's why Chryslers have usually had longer warranties than Fords, and Korean cars have some of the longest warranties of all.

I prefer SDM in lenses due to their near silent focussing which is great for event work. Yes I have had a SDM failure on the DA* 50-135 but since the repair it works flawlessly. I also have the DA*16-50, DA*60-250 and the DA*300 and wouldn't hesitate to get another SDM lens.

Pentax should offer at least a 3 year warranty on lens as I recently purchased at Sigma HSM that comes with a 10 year Canadian warranty.

All the stressing over this issue is way more than the small amount to fix the issue in the unlikley event of a failure.

Dale

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