Sigma 17-50mm F2.8 EX DC OS HSM

Best moderately priced 17-50mm lens on the market today – This full frame sensor lens also works perfectly on cropped sensor mounts. The lens produces sharp pictures and fine details down to F2.8. It has image stabilization which is an absolute must shooting longer low light exposures. This lens replaces my 18-55mm Canon kit lens, and should easily demonstrate the quality.

EXCELLENT QUALITY LENS FOR HALF THE PRICE! – Comparable with Canon's 17-55 f2.8 IS in terms of quality. Sigma's price is better by a mile though. Great investment!

Real value for the money – This lens is too good compared to the competitors in this range.For its price the output we get from this lens is very impressive.User friendly and focus is very good.Especially if we stop at f4 onwards ,the pictures are very sharp and probably any good filter with it goes well even in sun light pictures. Sharp lens Too bulky and bit heavy

This has become my main lens – Typical of later Sigma's, a fairly large heavy piece of kit, but very very sharp. Some complain about the zoom ring going in opposite to most lenses, but it has never bothered me. At almost half the price of the equivalent Pentax zoom, this was a no brainer, other than size and weight and lacks any weather sealing. It tests as a very sharp lens… Read more

and my portraits have proven that.

Build quality excellent. Sharp, sharp sharp...........value for money/ build quality A bit on the heavy side

Great lens! – I bought this lens to replace the kit lens for Nikon D90 (18-105). The image quality is absolutely fantastic given there are enough light and the OS system is also a great extra feature. The only problem I have is when shooting in low light environment, the auto focus does not work as smoothly and images are not as sharp (which I heard is a… Read more

common issue with Sigma lenses)

Overall it is a great lens, I have not taken it off from camera body since I bought it!! Very sharp image when enough light, large aperture, OS available Poor auto focus at dim environment

Really sharp at a good price – First I bought a Pentax 17-70 f4 and was disappointed with its IQ. It was quite soft wide open at f4. So I returned it and bought a Sigma 17-50 f2.8 instead. This lens is much better than the Pentax 17-70. It is very sharp even wide open at f2.8 and the colors are very good. Autofocus is slightly below the Pentax but good enough for me. I… Read more

wholeheartedly recommend this lens.

My only complaint is that it consistently overexposes on my Pentax K5 that I have to permanently set the camera to underexpose by 0.7 stop in order to compensate. Exposure metering for this lens on a K5 doesn't seem to be as accurate as exposure metering with my Pentax 50-135 which is dead on most of the time. image quality, colours, price is not too bad No weather sealing, exposure metering not quite as good as a Pentax lens (but ok)