[jatrax]

Waoow, you satisfy yourself with this kind of not even official workaround.

I'm sure Norm can reply if he wants but deliberately miss-reading what he said just to start an argument does not really help the discussion. He stated that Pentax gives another option rather than get an expensive lens repaired or replaced as you would need to do with other brands that do not have a screwdrive mechanism built in.
I've had my 16-50 since 2010 or 2011 and when it failed I got it fixed. It failed again and I chose to convert to screwdrive, that was my option because Pentax gave me the choice.

[TwoUptons]

I bought my 16-50 about five years ago, and it's one of the best lenses I've ever used. Optically, its flaws are nothing compared to the flaws I put into the photos I shoot with it...

I won't speak to the SDM issues as I haven't had any, touch wood :-)

It did need some focus calibration on my K10 when I first bought it, but that was no big deal, and it focuses fine now, quick and quiet.

It is a big, honking thing, and looks a bit silly on a K01, and balances poorly on the mirrorless, though it suits the K10 perfectly. Again, no big deal. In fact, put it on the K10, use a flash bracket, and the Canikon people start wondering who I am and who I'm shooting for...

The only thing I really don't like is how badly it vignettes with the onboard flash. At anything under 50mm (and even then if I left the hood on, even reversed) it shadows the flash and puts a big dark blob at the bottom of my photos. And I don't always want to fire up a Metz when I'm chasing a toddler...

-Eric

[Stagnant]

I went through three copies of this lens and my experience far has been far from positive. <br />
* The first one was returned due to dead electronics, most likely SDM.<br />
* Second copy went through multiple maintenance procedures: stiff focus ring, stuck focus ring in cold weather, decentering, focusing precision issues, mainboard replacement, wobbling front element. It was replaced after I complained to Pentax Europe (I refused to sign papers after the lens returned from service, because nothing was fixed). <br />
* Third copy had focusing issues at 50 mm, both CDAF and PDAF. <br />
Decentering, then same focusing issues and again decentering. It is now on its way to service. <br />
Most of the issues were never properly fixed during the maintenance. I suspect that the quality control is insufficient, manufacturing quality / design is lacking and / or European service is really bad. <br />
No trust left.
[Edit]The kit lens 18-55 WR, that came with K-3 proved to be more reliable.

[GeneV]

It is hard to know, isn't it?

There was a Pentax engineer who said in an interview that they had changed one of the parts in the 16-50 because it was prone to failure, but it certainly wasn't an official Pentax statement admitting there even was a problem.

I have had a 16-50 since 2008 and it works fine, but you never know if it will bite the dust down the road. Of course, switching it over to screw drive is a really good option for SDM failures and makes me feel comfortable that even if my SDM breaks, I'll continue to use the lens.

If it did bite the dust a few years down the road, a decade of use out of a product with an electromechanical component is not too shabby.

---------- Post added 01-11-16 at 09:11 AM ----------

So the fact that there are hardly any complaints about the 16-50 now has gone un-noticed in your reality?



The screw drive lenses are quite reliable, and the 16-50 has screw drive built in. We aren't talking about a Nikon or a Canon where if your AF motor goes your choice is either have it repaired or use it as a manual focus lens. Pentax gives you a third option.

The difference in the number of complaints is more noticeable if you have been around here for 7-8 years. I don't doubt that they still swing and miss on a few, and that happens with other brands as well.

[Bophoto]

IN post #3 I say that i send my 16-50 in, it was in April -15 (and i payed for it (diden´t find my receipt), 3 years warranty in Sweden /EU? on SDM leses) . Now i din´t use it in some months (have to many lenses) and autofocus din´t work again, but i try liveview and get back for some time and it works now ...
The problem can be some oxidise somewhere in the lens/motor if it works if you use it twice a month.
But if Pentax has find the problem, thy do they use DC motors now?

[normhead]

Well , I had two SDM lenses delivered new in 2014, one out of two was broke after using it right out of the box. The second good copy worked fine until now. I guess if you receive a lens with defective SDM, you return it immediately to the dealer, not a big issue. The issue is when the lens SDM is broke after a couple of years of usage, then the cost of repair and annoyance is for you. I don't remember of any press release from Pentax stating in bold that they've addressed the SDM failures on their DA* lenses. However, they've certainly made a major change on the DC lenses, but unfortunately , there's no DA* 16-50 f2.8 DC WR. To be on the safe side, you can still get the 16-85 instead of the 16-50.

If you buy a lens with an electric motor in it, it can fail. biz-engineer's failed. That's tough luck, but every camera companies lenses fail. If SDM hadn't been fixed there would be a lot more than one or two guys complaining. Consider it fixed. Statements like "I don't remember of any press release from Pentax stating in bold that they've addressed the SDM" add nothing to the discussion. "In bold", has nothing to do with it.

[Scorpio71GR]

My 16-50 is a year old and 2000 photos later it is still going strong. It is one of my most used lenses. I did not really buy it for the SDM motor, but more for the excellent IQ, build quality and weather sealing. The silent focusing is nice I will not deny that. It seems the amount of complaints has gone down but I have heard of people with newer copies that have failed. Yes the Sigma can be purchased cheaper but there is a big difference between 17mm and 16mm. Plus with the weather sealing on top of that of course it is more expensive. It seems that people think no other lenses fail but Pentax. All manufacturers have issues like this as well. As Norm did state, if those lenses do fail you have two options. Get it fixed or focus manually. Screw drive is the option Pentax gives us. Some may not like it but if your Cannonikkon lens fails, you better get your wallet out, that is the only option you have. I was on a photo shoot last year where two cameras failed. Both were full frame cameras. One person had her 70-200 lens just lock right up. That was a $2000 lens. If my 16-50 does fail I will most likely just convert it and move on. I would rather enjoy taking photos than complain.

[Canada_Rockies]

My 16-50 is a year old and 2000 photos later it is still going strong. It is one of my most used lenses. I did not really buy it for the SDM motor, but more for the excellent IQ, build quality and weather sealing. The silent focusing is nice I will not deny that. It seems the amount of complaints has gone down but I have heard of people with newer copies that have failed. Yes the Sigma can be purchased cheaper but there is a big difference between 17mm and 16mm. Plus with the weather sealing on top of that of course it is more expensive. It seems that people think no other lenses fail but Pentax. All manufacturers have issues like this as well. As Norm did state, if those lenses do fail you have two options. Get it fixed or focus manually. Screw drive is the option Pentax gives us. Some may not like it but if your Cannonikkon lens fails, you better get your wallet out, that is the only option you have. I was on a photo shoot last year where two cameras failed. Both were full frame cameras. One person had her 70-200 lens just lock right up. That was a $2000 lens. If my 16-50 does fail I will most likely just convert it and move on. I would rather enjoy taking photos than complain.

I won't bother repairing mine if the SDM fails. It's handy to have AF available, but in the range of focal lengths covered by this lens, manual focus is perfectly adequate.

PS: I bought mine in 2007.

[Qwntm]

I went through three copies of this lens and my experience far has been far from positive. <br />
* The first one was returned due to dead electronics, most likely SDM.<br />
* Second copy went through multiple maintenance procedures: stiff focus ring, stuck focus ring in cold weather, decentering, focusing precision issues, mainboard replacement, wobbling front element. It was replaced after I complained to Pentax Europe (I refused to sign papers after the lens returned from service, because nothing was fixed). <br />
* Third copy had focusing issues at 50 mm, both CDAF and PDAF. <br />
Decentering, then same focusing issues and again decentering. It is now on its way to service. <br />
Most of the issues were never properly fixed during the maintenance. I suspect that the quality control is insufficient, manufacturing quality / design is lacking and / or European service is really bad. <br />
No trust left.
[Edit]The kit lens 18-55 WR, that came with K-3 proved to be more reliable.

This is why I have not exchanged the 50-135 I have. It's sharp, focuses accurately with zero adjustment, has very little fringing and seems to work fine. EXCEPT for the little birdie chirp chirp when it starts and stops focusing.


If it going to act up I hope it does it this summer when it's still under warranty and not next summer!


Other than the bird sounds, the lens is a winner!