[ravenorxs]

Hi there,

I'm sorry if this question has been answered to death. I'm looking to get the Pentax DA* 50-135mm zoom lens. I've read here and there that some DA* lens are prone to having SDM issues. Especially this article Pentax SDM Failure Survey Results - Photographic Articles - PentaxForums.com. Could somebody:

1) Go into some detail of what causes the SDM failure? Is it random? Being unlucky? Are there things to do to prevent it?

2) If a lens is out of warranty will Pentax still accept the lens for repair? How much will it usually cost?

3) I've seen 1 or 2 posts on the internet about DIY fixes that seem to work. Lens might not be fully new (i.e some weird noises) but still regains focusing ability. How reliable is this? Is it worth it to try and fix it myself if something happaned?

I might potentially be meeting a seller for a used DA* 50-135mm. The price is ridiculously cheap so I just want to see what my options are in case something happens down the line.

Thanks!

[Na Horuk]

1) Go into some detail of what causes the SDM failure? Is it random? Being unlucky? Are there things to do to prevent it?

Seems that mostly older zoom SDM lenses are problematic. Pentax claimed that the SDM issue has been fixed, so buying a new lens shouldn't cause problems. I think lenses like the DA* 55mm also had very few problems

2) If a lens is out of warranty will Pentax still accept the lens for repair? How much will it usually cost?

Pentax has repair centres. Warranty and such depends on local laws. You can also send it in if its out of warranty, but it will cost you. Not sure how much, depends on the problem. Sometimes the lens might have to get sent to Japan, so it might take a while.

3) I've seen 1 or 2 posts on the internet about DIY fixes that seem to work. Lens might not be fully new (i.e some weird noises) but still regains focusing ability. How reliable is this? Is it worth it to try and fix it myself if something happaned?

There is a way to turn some SDM lenses in screw-drive, so the camera motor moves it instead of the SDM. This means the SDM's failure is bypassed. Not sure if it works with all lenses, and I think you need an older camera body to deactivate the SDM. I think someone offered to do it for people, if they send in the lens.

The DA* 50-135mm is a great lens in terms of IQ. For SDM failures, please look at threads specifically about that lens. I think the lens with most SDM failures was the 16-50mm, but even this was supposedly fixed in new batches (a year or two ago)

And probably people with hands-on experience will also post soon

[VisualDarkness]

My brother use his 50-135, that he bought used, without any problems at all with the SDM. So it's not doomed to fail all the time as posts and stats may make it look like. 'togs like Heie here on the forum has used his SDM lenses in extreme situation and praise their reliability.
Are there problems, yes.
Will you most likely face them, probably no.

[HYS]

I had the chance to experience the so called "SDM problem" with my 17-70. The process of focusing started to be "lazy",
whimsical, slower and on 70mm refused to work. And all of this was distributed in time - approximately 1 year of downgrade
tendency. And finally stopped to focus in any setting. The local Pentax service repaired the lens by changing the SDM motor
(~$100 fee) with a new one.
Since then the lens works perfectly. I like it, this lens is very good.
The man in the service told me that this kind of failure is really rare.

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Last edited by HYS; 02-22-2014 at 09:55 AM.

[GPZ]

Sent my 50-135 to Pentax Canada in 2012. Cost $115 CAD for new motor + $160 labor. Took two weeks to have it back.

[ravenorxs]

Thanks for the replies. I'm hoping if I do get the lens (it will actually be 3rd hand) that I won't have any problems. It still does seem like a hit or miss with regards to reliability though. Hopefully even as a 3rd hand lens, the lens itself was manufactured fairly recently.

[Canada_Rockies]

My DA* 16-50 was purchased in 2007, and has not failed. I think the true failure rate is about 5%, which is higher than most brands, but not as catastrophic as the posts would indicate. My DA* 50-135, also purchased in 2007 and was a bad one. It failed three times, the third time out of warranty. I made a trade for a noisy, slow to focus, DA-L 55-300 and am getting decent results, but I think I made a boo-boo. I should just have kept it and used it as a manual lens. I really miss the fast aperture and the Image Quality of the lens.

Sometimes you turn left when you should turn right.

[Ole]

You could check our serial number database, that will give you an idea of failure rate and also about from which serial number and year the motor design was changed for the better.

[DSims]

I might potentially be meeting a seller for a used DA* 50-135mm. The price is ridiculously cheap so I just want to see what my options are in case something happens down the line.

The big question is what is the cost of not getting the images you want. You may not want to pass it up.

Make sure the image quality is good on this copy, and it appears to focus fine.

But as always (as with buying a used car), ask about why they're selling it, and look/listen for any signs that there are problems. And don't ignore the signs that something is wrong. If something's up, don't fall for the low price.


But a lens is not as complex as a car (in terms of what can go wrong), so the risk of cost and mental anguish is lower as well. As with any lens, significant fungus is about the worst problem you could have (and you don't want that).



I never advise people to stay away from this lens because of fear of SDM failure. But your statement that it's "ridiculously cheap" makes me suspicious of this particular copy, whether it's an SDM problem or something else.

[Na Horuk]

But your statement that it's "ridiculously cheap" makes me suspicious of this particular copy, whether it's an SDM problem or something else.

Yeah, definitely ask the seller if the lens exhibited any AF quirks and ask for some sort of warranty/guarantee
Or just snatch up the lens and then have it repaired/SDM disabled. A good deal is a good deal, and as long as the optics work nicely!

[Gerard_Dirks]

Hello

I am now also a victim of an broken SDM lens. It is a shame that we need to send lenses for repair and pay hunderds of $, £, € and CHF for this repairs and have the risk of a 2nd, 3th or 4th repair.

If Pentax was as VW, BMW or GM their would be a world wide callback and repair for this item.

It is a blame that we need to pay for a repair that seems to be 100% a design or construction error

Let's hope Ricoh will save the reputation of Pentax and start an Extended Repair Program for this SDM lenses, or to we need to start a petition to force such a replacement Program

Regards
Gérard

[Sandy Hancock]

I have had two DA*16-50 fail on me. One was repaired under warrantee an subsequently sold, the other I hacked to operate by its screw drive mechanism and it remains one of my most used and most valued lenses.

The DA*55 I bought had a dead SDM right out of the box. It was replaced by the vendor, but recently (two years of regular use later) its SDM also failed. It has been fixed at my expense because it has no screw drive mechanism.

My DA*50-135 and DA*300 have had no SDM issues at all. Touch wood. At least it can be converted to screw drive if necessary.

[Gerard_Dirks]

Does other manufacturer, like Canon & Nikon, has simular quality problems with particular products in their portfolio.

I am very frustration, especially after upgrade my hobby with the highend and expensive products of pentax and at the end get such a garbage :-(

[Na Horuk]

No, Canon, Nikon, Sony, Olympus, Panasonic never have any problems. It is only Pentax that at the end get such a garbage. [/sarcasm]

[Sandy Hancock]

no, canon, nikon, sony, olympus, panasonic never have any problems. It is only pentax that at the end get such a garbage. [/sarcasm]

roflmao!