[CRPhoto]

Wow, I just started looking into replacing a 28 - 70 2.8 Sigma lens and considered the Pentax 16 - 50. I didn't realize they were known for having problems. That's kind of discouraging when looking at the amount I was considering dropping on a new one. Wondering if I should consider a better version of a Sigma or a Tamron instead then? Will be anxious to hear how it works when you get it back. Hope you don't have any more problems with it.

Even with the SDM failure on my lens it's my favorite one. As mentioned above, the SDM problems supposedly had been fixed. So if you get a newer one you shouldn't have a problem. The build quality, optical quality and silent motor keep me from selling it. I do think the current price is a little high.

[Fries]

Just to confirm that there are people satisfied with this lens without having autofocus problems; I bought mine in the spring of 2009 and it is my most used lens. Never experienced the dreaded SDM failure. But eventually I expect my primes to outlive the DA*16-50. If it does fail I can live with that.

[Allison]

Wow, I just started looking into replacing a 28 - 70 2.8 Sigma lens and considered the Pentax 16 - 50. I didn't realize they were known for having problems. That's kind of discouraging when looking at the amount I was considering dropping on a new one. Wondering if I should consider a better version of a Sigma or a Tamron instead then? Will be anxious to hear how it works when you get it back. Hope you don't have any more problems with it.

I wouldn't worry about it too much, since the same sdm failures that people complain about also affected the 50-135 and I know how much you love that lens. There were bad copies, as with anything, but I think the good ones well outnumber the bad now.

I have heard the same complaints made about sdm being made about hsm on sigma and tamron.

[snake]

SDM wasn't the only complaint about the 16-50. We can't always forget about the decentering issues, which were overshadowed by the massive SDM failure problem.

And I wouldn't be too sure about the failures being behind us.

[Docrwm]

The plural of anecdote is not data. We collected data here in on SDM lenses and they do fail, far more often than non-SDM lenses. While I am always happy to hear that folks have had good experiences with their particularly lens, the fact of the matter is that SDM in Pentax lenses is a problem.

[CRPhoto]

So I finally got my lens. It looks new. I can see some of the replaced parts (like here the hood screws into the lens, it was broken, now it's new! Optically is super clear. SDM feels quick. I haven't been able to fully tested, just got a couple of airplane shots and I'm happy with the performance. I'm using a K5-IIs so the pics look really really sharp! As soon as I get some more images I'll post them.

[CRPhoto]

And after a few months, it's going to Japan again! Good thing is still under the repair warranty.

[Docrwm]

And after a few months, it's going to Japan again! Good thing is still under the repair warranty.

SDM or another issue?

[CRPhoto]

Aparently SDM. The lens focuses but then the camera refuses to take the picture. I switch it to Manual en it takes the pic. It's similar to what it did before.

[Docrwm]

Aparently SDM. The lens focuses but then the camera refuses to take the picture. I switch it to Manual en it takes the pic. It's similar to what it did before.

Sorry to hear that, glad for you that its still under warranty.

[Class A]

Wow, I just started looking into replacing a 28 - 70 2.8 Sigma lens and considered the Pentax 16 - 50. I didn't realize they were known for having problems. That's kind of discouraging when looking at the amount I was considering dropping on a new one.

For a long time I was sceptical that the anecdotal stories about SDM failures could be actual evidence for a systematic problem.

Meanwhile, I've read so many problem stories that I no longer believe that SDM issues are not any more frequent than other failures and the whole "SDM hysteria" is just a matter of happy people keeping quiet and a few affected ones shouting loud.

What I found particularly irritating was the quite high number of reports regarding repeat failures. Someone's lens fails, typically shortly after the warranty ends. It gets repaired, works for a while then fails again. It gets repaired a second time, works again for a while and than fails again (now for the third time). Both 16-50 and 50-135 are often associated with such horror stories.

Optically, the Tamron 17-50/2.8 or one of the equivalent Sigma models can hold their own against the Pentax 16-50/2.8. In an unfortunately no longer available comparative review between three lenses (Pentax, Tamron, Sigma), the Pentax often came last or second. In many of the sample images, the third party lenses gave better results, as far as I was concerned. Optically, the 50-135 is excellent. The 16-50 is not in the same league, AFAIC.

[tomwil]

Optically, the Tamron 17-50/2.8 or one of the equivalent Sigma models can hold their own against the Pentax 16-50/2.8. In an unfortunately no longer available comparative review between three lenses (Pentax, Tamron, Sigma), the Pentax often came last or second.

I'm confused. Is this comparative review the one you are mentioning, or is there another review now missing?

[snake]

I went with the Tamron 17-50 and never looked back at not getting the Pentax. I especially wasn't happy with the edge sharpness and distortion and seeing decentering in several copies. SDM aside, which is not exactly something I want to deal with, especially when Pentax authorized dealers are not too keen on selling them.

[CRPhoto]

Optically I'm happy with my copy. The WR is important to me so it's my only choice in lens. The SDM is annoying for sure, but for now is still under warranty so I'll just ship it. When it comes back, I'll have another warranty time, and with the use I give this lens, it won't be long for me to realize if the repair worked or not.
Another thing is that I got this lens really really cheap from Wolf long time ago.

[snake]

Optically I'm happy with my copy. The WR is important to me so it's my only choice in lens. The SDM is annoying for sure, but for now is still under warranty so I'll just ship it. When it comes back, I'll have another warranty time, and with the use I give this lens, it won't be long for me to realize if the repair worked or not.
Another thing is that I got this lens really really cheap from Wolf long time ago.

Most people can't afford that kind of downtime. I know I can't give up my 17-50 for repairs for months at a time. And in my case, Tamron is nearby in my country, plus I got a 5 year warranty.