7 out of 10 points and recommendedGreat range, Good IQ, Faster than 18-55 kit lens, Good valueQuality (focus) issues
I bought this lens while on holiday in Australia and after getting back to NZ, I was disappointed with the results. A large number of images were blurry and not sharp. Focus tests showed up a lot of back focus (and sometimes even front focus) at different focal lengths. I sent the lens back to the NZ support agent (who, to their credit, honored the "Australia Only" warranty). It ended up away for 4 weeks, leaving me stewing about it!reviewed March 14th, 2014 (purchased for $295)
If this was the end of the story then the rating would be maybe a 2, however...
Upon getting it back (apparently after recalibrating the autofocus) I immediately noticed a big difference in performance. I now had a very usable, flexible lens that rendered nice colors! Sure at some focal lengths it is still less sharp than others (around 50mm is not its strong point) but never less than acceptable for a zoom IMO. My copy is actually quite sharp at 70mm which is a focal length I use quite a lot. I also use it a lot at the other end (around 20mm) which is also very good.
Having f2.8 available (even if only at wide end) is really quite useful and has allowed me to capture shots that I think would have been more of a struggle with only f4 available.
I also have the Pentax 18-55 kit lens and in comparison the Sigma has:
* Similar centre sharpness
* Somewhat better on average across frame
* Faster across the range (useful)
* Much better focal range (for me anyway - far less lens swaps)
Without the initial quality issues I would have rated it a 8 based on value for money. However factoring in the initial issues I have settled on a 7. Perhaps it should have averaged lower but the bottom line is I like it
I have since got a Pentax 18-135 and find the new Pentax is better all round and has WR. Since then my 17-70 is no longer used.
10 out of 10 points and recommendedVery sharp, focus limiter, nice feel to it, good bokehSpoils the others lenses
I was worried about the purchase at the time (you can never be sure of what you are going to get with online auctions) but now I realise I got a bit of a bargain.reviewed February 8th, 2014 (purchased for $330)
The focus limiter is a very useful feature and I now would not like to be without it (pity DFA macros don't have one). Sharpness is impressive. Even at f2.8 it pretty sharp and at the other end f16 is very useful (and surprisingly sharp still) for macro work.
I find it quite hard to write negatives on this lens. Its a lovely piece of glass in a solid package and a useful feature set.
I don't mind the size / weight because, for me, its quite easy to steady it (I find weight can help) and not so heavy that you tire.
If I was going to fussy I would say that it would be nice if it was a bit faster for portrait work but given that it is a macro lens then f2.8 is respectable.
One thing for sure is that it spoils most of my other lenses because it makes their performance look average in comparison!
Sunset over a damaged city - f11; http://www.flickr.com/photos/kiwi_jono/5956560966/in/photostream/
Lone Tree - f5.6: http://www.flickr.com/photos/kiwi_jono/7357082932/in/photostream
Tim Beach - f9.5: http://www.flickr.com/photos/kiwi_jono/6061255589/in/photostream/
Icicles - f3.5: http://www.flickr.com/photos/kiwi_jono/5990225908/in/photostream/
8 out of 10 points and recommendedplenty sharp, not heavy, surprisingly ruggedCould be faster
My version is actually the DA-L variant which is largely the same (identical optically) except for having a plastic mount and not coming with a hood.reviewed February 8th, 2014
I might as well start out by saying - I like this lens.
I got this in a K-x kit and so far I have taken a lot more keepers with this lens than I ever did with the 18-55 kit lens. Also have some older lenses like Super Tak 200 f4 (which I like) but keep coming back to this lens for its shear convenience with decent IQ.
I find mine to be decently sharp - particularly at f8.
A month after I got it, I had a dumb incident with my camera falling out of my camera pack (don't forget to close those side flaps!!!) 2 feet or so on to concrete and it landed on the 55-300 lens. I was very distressed as usually I'm so careful. Can't believe it but there was no ill effects (mechanically, optically or cosmetically) to the lens or camera - not even a mark!
70mm f10: http://www.flickr.com/photos/kiwi_jono/4523155160/
230mm f5.6: http://www.flickr.com/photos/kiwi_jono/4977579341/
300mm f7.1: http://www.flickr.com/photos/kiwi_jono/4502582390/
9 out of 10 points and recommendedRelatively small, very good centre sharpness. Good AF, WR, build, and focal rangeCorners 85 - 135, Corner CA at wider angles
I have a number of zooms, including original Sigma 17-70 and Pentax 18-55. This lens beats them in most ways (including overall sharpness).reviewed January 30th, 2014 (purchased for $318)
The real strengths are the relatively compact size (versus flexibility and performance), excellent auto focus and Weather Resistance. I'm not worried about taking this lens anywhere.
Yes the lens does suffer with soft corners at the long focal lengths but IMO the lens is still very usable and i have had some good usable results at 135mm (which I would have missed out on with the 17-70).
I did some detail tripod test shots (uniform fences etc) against my Sigma 17-70 and this lens stacks up very well. Often sharper at same focal lengths and aperture settings (even frame edges over most of the range).
I don't really agree with Klaus's final conclusions on Photozone (see: http://www.photozone.de/pentax/597-pentax_18135_3556), although you can't fault his technical measurements and methods which I have a great deal of respect for.
If you compare the results for this lens to other offers like Nikons http://www.photozone.de/nikon--nikkor-aps-c-lens-tests/634-nikkor181053556vr , I think the Pentax actually stacks up pretty well. Its much more compact, has WR, better build and generally better centre sharpness.
I got this lens for the WR and I'm much more impressed than I thought I would be.
60mm f6.7: http://www.flickr.com/photos/kiwi_jono/12021282873/
31mm f8: http://www.flickr.com/photos/kiwi_jono/12021352614/
31mm f11: http://www.flickr.com/photos/kiwi_jono/12021300923/
9 out of 10 points and recommendedVery sharp center, nice feel, good auto focus, very useful rangeCorners at 10mm could be sharper
Although I can't compare this to other UWA lenses I can compare it to other zoom lenses I have (such as Sigma 17-70) and this lens beats them hands down. Feel and build quality is excellent. HSM focussing is wonderful. Flare resistance is surprisingly good for a UWA. I love this lens and the perspective it allows. At f3.5 it has very good sharpness (at least in center) and I find f3.5 particularly useful for indoor shots or where you want a bit of bokeh on close ups (can only get so much on a UWA). Colours look nice tooreviewed September 20th, 2013 (purchased for $515)
Example image at 16mm (f8): http://www.flickr.com/photos/kiwi_jo...in/photostream.
Example image at 10mm (f5.6): http://www.flickr.com/photos/kiwi_jo...in/photostream
10mm f11 sharpness: http://www.flickr.com/photos/kiwi_jo...n/photostream/
Bokeh example at 20mm (f3.5): http://www.flickr.com/photos/kiwi_jo...in/photostream
Creative examples at 10mm http://www.flickr.com/photos/kiwi_jo...in/photostream and http://www.flickr.com/photos/kiwi_jono/8244294796/
Contrast f9.5 at 20mm: http://www.flickr.com/photos/kiwi_jo...in/photostream
My only criticism is that at 10-12mm the corners can be soft below f5.6 and a still a little soft below f8. Still perfectly useful in my view. At 12 - 15mm corners are perhaps a little soft at times wide open. And from 15-20mm the quality is very good across the frame from f3.5 (and better IQ than my 17-70 at 17 - 20mm).
Overall I love this lens!
9 out of 10 points and recommendedFairly small and light, fast autofocus, good f2, tack sharp from f4Build could be better (normal for FAs though), autofocus could be quieter
I have had this lens for a few months now and its on my camera most of the time, so time for a review.reviewed February 8th, 2014 (purchased for $350)
Its a great lens and is particularly useful on a crop DSLR (field of view on crop is close to 50mm full frame). Look forward to trying it on my ME Super too.
Definitely had to spend some time fine tuning the auto focus (on the K-5) because it was out quite a bit. Once I dialed it in though it is returningg very sharp photos.
Its pretty sharp in the centre of the frame at f2 (a bit soft in the corners) and I find it very usable. Even better the contrast wide open is surprisingly good. Sweet spot seems to be f5.6 where it is very sharp across the frame. f4 is nearly as good as f5.6.
I have noticed a little CA at times but its pretty minimal.
The supplied hood is good and can be fitted in reverse over the lens body when not in used - protecting the lens.
So far I am happy with bokeh and have not seen anything I would call ugly but then when I am looking for bokeh I shoot mostly wide open. The lens can focus relatively closely too - which helps.
The more I use this lens, the more I'm liking it. I'm seeing a lot of good results even at f2. For example take a look at the second f2 image taken in bright contrasty light - there is a little CA (have not attempted to remove) on right side of the dragon head but otherwise its impressive with good contrast.
At f2: http://www.flickr.com/photos/kiwi_jono/10399776183/
At f2: http://www.flickr.com/photos/kiwi_jono/11316786296/
At f2: http://www.flickr.com/photos/kiwi_jono/12146154904/
At f4: http://www.flickr.com/photos/kiwi_jono/11233812534/
At f5.6: http://www.flickr.com/photos/kiwi_jono/11320538734/
9 out of 10 points and recommendedSmall, very sharp stopped down, fast, full frame, very good valueLow contrast at f1.4, bokeh can be a little nervous wide open sometimes
IMO this lens really comes alive on the K-1. The focal length is now a perfect "normal" lens and very general purpose. Yes it can look a bit soft wide open but this is mostly low contrast (although sharpness is not that great either).reviewed December 10th, 2016 (purchased for $200)
Its size is very compact for the speed and is very easy to carry around. I have found on my K-5 the bokeh can sometimes be a little nervous wide open but much better at f2. Not sure if this will change on the K-1 yet but first test shots look promising (possibly because focus distances are nearer for same subjects).
1. K-1 @ f1.4: https://www.flickr.com/photos/kiwi_jono/31429838411
2. K-5 @ f2: https://www.flickr.com/photos/kiwi_jono/16059022872