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Pentax smc DA* 50-135mm SDM Issue

Started Dec 21, 2013 | Discussions thread
DAVID MANZE Veteran Member • Posts: 6,390
Re: Same old explanations
1

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.!

-- hide signature --

-- I see nothing from these statistics which underline the reliability of Pentax's SDM, a good figure from a manufacturer should be around 1-5%, 8% shows a problem, above 20% is "inexcusable". Are you seriously putting these figures forward as proof of reliability? You cite 1 in ten as a good figure?

Anyway,the problem has been fixed now, but unfortunately Pentax refuses to give any serial numbers to differentiate between the change in SDM motors and as old stocks remain, there's no way of knowing whether you've bought an early or recent motor.

PS. Statistics showing zero% just show insufficient statistics.

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