SDM failures horror stories

I've heard that too much this week so lets gather all the SDM stories of all the members here too see how bad it is.

I didn't have had any problem with my DA*16-50 and DA*50-135 so I can't tell you off any horror stories.
Although my view on the SDM failure is if the SDM motor is that bad then the DA*200, DA*300, DA*55, DA*60-250 and DA 17-70 would also suffer a lot since they use a SDM motor so for how much can the SDM motor be to blame for all the failures?
Wouldn't a poor AF system design be a better explanation of most failures?

Let's find out shall we.

Never had any problems either but only have two.

I don't have any problem with my DA*16-50 and DA*50-135 either - focus is smooth and fast.

C

I find my 17-70 sometimes fails to find focus mostly at longer focal lengths in dim light. I understand that this is normal for the 17-70 and has something to do with the small focal steps on this lens. It is easily remedied by applying slight pressure to the focus ring - it locks focus quickly then.

I have three SDM lenses and have had no problem with any of them.

Never had a problem with DA17-70, DA50-135, or DA300.

There's already an existing (long) thread about this, no need to duplicate.

Actually this isn't a duplicate because I was asking for the horror stories, not my fault every one commented that they didn't had a failure or story too tell

The purpose was to see if it truly was the SDM motor or that it could be something else that was at fault.

edit: Actually let's take the opportunity to make a list of failure per lens so Gwyn and Thordell, which SDM lenses do you've?


The first number is the number of times the lens is mentioned and the one between the (#) is the number off them that failed

DA 17-70 - 2 (0)
DA*16-50 - 2 (0)
DA*50-135 - 3 (0)
DA*60-250 - 0 (0)
DA*55 - 0 (0)
DA*200 - 0 (0)
DA*300 - 1 (0)

Stefan - if you want horror stories go to the american Pentax site. Everyone there who has ever had an SDM lens has been killed by it and those who have more than one have had multiple deaths. It seems that when they go critical, they can take a whole state out.

Put me down for four deaths please.

They also come up with gems like"the index mark (?) on a polarising filter should be pointed toward the sun---or was it half way between the sun and the horizon.

I have the 17-70, 50-135 and 60-250

Oggy : I can not follow you for very well, are you joking?

Thank you Gwyn.
Jackie also has the DA*60-250 but don't know about the other lens she has.

DA 17-70 - 3 (0)
DA*16-50 - 2 (0)
DA*50-135 - 4 (0)
DA*60-250 - 2 (0)
DA*55 - 0 (0)
DA*200 - 0 (0)
DA*300 - 1 (0)

We had our DA*16-50 replaced as it just 'went faulty', actual focussing went way way out overnight, not attributed to an SDM failure though, but replaced. No problems with replacement

DA* 50-135 has been back 3 times for SDM repair, still gets sticky when not used. Rubber round the zoom ring has now come loose, presumably where it has been taken apart so many times. Also a rubber o-ring is visible in the focussing window, again presumed to have come loose from multiple repairs. Have lost faith in this lens ever being reliable.

55mm, 60-250mm & 300mm, all perfectly fine!

Just took out the 50-135 for the 1st time since the wedding last week. The focussing was stuck for the first 5-10 seconds or so, then was fine afterwards.

What are you hoping to achieve with this thread, Stefan?

G

It doesn't look as though there's a mass of horror stories after all.

There are failures with every make of lens, Pentax included, but as a percentage it seems relatively low.

It might seem relatively low as a percentage, but it is in my opinion still high relative to the norm for such things. We do not read the same noticeable numbers of Pentax body users having the HSM on their Sigma lenses fail. (front-focusing is another matter! I mean HSM working properly when the lens arrives but then failing - the problem for which SDM is under the spotlight)

Surely with Sigma's reputation for poor quality control, and the fact that (with current Pentax prices) many Pentax body owners are buying Sigma HSM lenses, there should be an equal if not greater volume of complaints from Pentax body users about Sigma HSM if in fact SDM does not have worse problems than other brands.