Originally posted by GlennG Good evening, John. I have the DA 17-70 and had the SDM repaired in early 2014. The repair was done in Chandler, AZ (forget the name - CRSS?) and they reported that they installed the updated SDM motor, so it should perform better and more reliably than the original. The SDM was good for about a year or so, but eventually the SDM issues returned. In almost all scenes the lens has trouble focusing in the 50-70 mm focal range. You can fiddle with it enough to get the camera to eventually take the photo, but it may not be in good focus. Also, and I'm not sure if this is related, the camera will often return the reported focal length as "43", which seems to be a default setting of sorts for when there is a focusing problem. I took my DA 17-70 on a recent trip to Hawaii when my DA 16-50 was unavailable. I got some great photos with the DA 17-70, especially in the under 50 mm range, but the overall experience brought back the frustrations I had when using the lens. It is unfortunate that this lens has this focusing issue. If the SDM could be bypassed like some other Pentax lenses I would gladly do that, but that option is not available. I love the photos, range, constant aperture that come with the DA 17-70; when it was right it was such a PERFECT walk around and travel lens for me. At this point, the 16-50 is my main lens and the 17-70 sits, waiting for me to come up with a forward plan for it. Not sure what it will be, though. At any rate, that is all the input I have for now. I hope you can glean a little useful perspective from this. Thanks. Glenn
Glenn (and all who responded)
Thank You Very Much. Your experiences are exactly same as mine. The first sign of trouble was the autofocus was hit or miss between 50 and 70mm and in the last few years I noticed if I did not use, or exercise it at least twice a week the SDM would be slow to start working. The repair is expensive $213 at precision plus the cost of shipping it. Based on the user reviews and the responses I received here this lens is something of a gamble. If you get a good one it is a really nice lens, but if you get a problematic one it is frustrating. My dilemma is with three bodies: K10D. K-5 and K-3 on a family outing all in use the 16-85 can't be on all of them. I am good with primes, but my wife and son want the convenience of a zoom. So for now, my 17-70 is a paperweight and I may look at another replacement, perhaps even one of the kit zooms 18-55 WR to 18-50 RE for my wife or son to use where they won't be as picky about image quality and camera weight as me. I noticed KEH and B&H both have used DA17-70 lenses in like new condition for not much more than fixing the one I have. My dilemma, Should I take another gamble on one of them?