Sigma 17-50mm F2.8 EX DC HSM for Pentax Fit

Having decided that I needed a good quality, fast portrait/landscape lens to compliment my telephoto lenses, I spent countless hours reading reviews (both user and professional) on this lens and the Pentax equivalent, the DA* 16-50mm. Whilst the Pentax came across as a 'Marmite' lens (people either loved it or hated it!) the reviews for the Sigma were very consistent ie it's a very good lens. Factor in the £520 premium you have to pay for the Pentax (ok, you do get weather resistance, 2 extra aperture blades and an extra 1mm at the wide end!) and, quite frankly, it was a no brainer. Straight from the box, this lens oozes quality. Taking it out of the padded, zipped case the weight tells you that you have a lot of good quality glass in this lens. Some people may find it a tad too heavy but it balances perfectly on my K50 (it weighs more than my Sigma 18-250mm tele lens!). Build quality seems fantastic for a lens of this price. Though it has a metal lens mount the body is made of plastic. Don't let this put you off as it feels top quality and very well nailed together. The zoom ring turns counter clockwise (not a problem for me as I have Sigma anyway) which some people may find strange but you soon get used to it. It's about a 90 degree turn from wide to tele and the zoom action is very smooth. Autofocus is very quick and accurate (especially on single point af) though as yet I haven't tested it in very low light. Don't take any notice of the minimum focussing distance, as with a bit of readjustment of the focus point and in the right light I've managed to get great quality images at half the recommended distance! When it comes to colour rendition and clarity this lens is truly astonishing. Colours are so accurately reproduced and the clarity of the test photographs that I've taken thus far is incredible. The focal point of close up images just seems to pop out at you. My time spent in PP has reduced dramatically and a lot of images just require a small amount tweaking. In summary, whilst it's early days yet this lens has blown my socks off!

It seems to work! Sometimes autofocus will not work exactly and I have to repeat but maybe depend on my camera Pentax k-20...?

I am using this lens with a K3 body. The K3 sensor out-resolves the lens but that is going to happen with a zoom anyway. The combination is a substantial piece of kit but well balanced; the K3 body is heavy for an APS design. This is an extremely useful general purpose lens with results that are going to be good enough almost throughout the range. Vignetting is high at 17mm f/2.8 but to avoid that it would need to be very much larger, heavier and more expensive and this can be partially compensated in software nowadays. The lens is even cheap enough not to worry about.

I have an old Sigma 400mm and loved it so I decided to go against my usual "Stick with PENTAX BRAND only". Having looked at the reviews I decided it was worth the risk. I am amased at the quality of this lens. On my Pentax K3 I ran thorough tests to check sharpness, distortion and colour. There is a very slight distortion at 17mm when getting close (no surprises there) but across the whole range the sharpness and colour is excellent. I'm so impresses I've ordered the 10mm-20mm F3.5 to go with it

Generally better than the 'kit' 18-55 DAL which was sold with the older K-series Pentax DSLR cameras. Wider max aperture which does not change through the zoom range - though this makes it a heavier lens. Very sharp definition around the centre, but disappointingly a bit soft at the edges of the APS-C frame.

Very good quality not as good as my pentax 18_135 but very smart lense now to try first taste shots look sharp enough but find out later,

I like it! It is a very large and heavy lens, but my photos look much better than they do using my old Pentax 18-55mm zoom. You will find my brief review, photos and histograms here: [...] It wasn't packed very well. There is no point in putting a sensitive lens in a large cardboard box if you then allow it to roll around inside!

Nice lens. Takes great photos - a noticeable upgrade to the kit 18-55 WR lens. Makes my K5 feel more like a pro-camera. It is nicely balanced too. Quiet. Lots of detailed reviews online of course - check them out.

Jan 16 2017 update I have been using it for a few months now. It has impressed me even more. On tripod along with pixel shift, it has far exceeded my expectations and photography has been my hobby for 40+ years. On stopping down to f/8 - f/10, edge performance is perfectly acceptable while center sharpness is exceptional. Wider apertures are ideal for portrait shots. The Tamron 17-50 I previously used has never delivered this level of performance. Original: This is a replacement for a Tamron 17-50 f/2.8 that I have since 2008. The reason for the replacement was AF accuracy that required substantial front focus adjustment and re-adjustment had to be made regularly to maintain acceptable AF. I bought this Sigma to determine if it would be better than the Tamron. AF was already quite acceptable without any focus adjustment. Once fine tuned, sharpness and resolution are stunning, better than Tamron. Using a K-3II on tripod and pixel shift engaged, I compared it to a Pentax 16-85 and a 50 f/1.4. In terms of resolution, it very slightly edges out the 16-85 at comparable focal length and aperture; I consider them equal for all practical purposes. It is usable even full open, stopping down improves resolution. It is very close to the 50 f/1.4 at f/2.8, but the 50 is much better at f/4 and smaller aperture. I like the Pentax 16-85 a lot but like to have a faster zoom for some low light situations or shorter depth of field that only faster lenses can offer. Build quality is high, typical of Sigma products. The zoom ring is smooth and so is the focus ring but I have not actually tried MF. I once dropped a Sigma 100-300 f/4 3 feet on an aluminum bench and then another foot or so onto concrete floor, not only the lens functions normally, there is no visible scratch on the lens as a result of the fall. The price of this Sigma is very attractive, especially if you can find a used one in good condition. Highly recommended unless you need WR.

I am using it for my pentax k5iis. Very good and smart replacement to the standart kit. Accurate and silent autofocus

Replaced a Pentax wide angle with this lens. Pentax has problems with their high speed motors for autofocus. Very pleased with this lens. Have had no vignetting except when using a polarizing filter. Minimal distortion at both ends of focal length but quick fix in LR. Have had one occasion of purple fringing but no green or magenta chromatic aberration. Minimal lens breathing, to which I don't even pay attention. Excellent value, especially at the price.

フリーランスのWEB＆パブリッシュデザイナーです。PENTAX K30で使用しています。 カメラが趣味というわけではありませんが、絞り×シャッタースピード×ISOや適正露出とかそのあたりは理解しています。 仕事で顧客企業の事務所、店舗の内観外観、スタッフさんの写真、商品写真、データのないロゴデザインなどを撮ることが多いです。動くものや暗いものを撮ることはほとんどありません。 いままではキットレンズや安いレンズで、どうしてこうぼんやりした写真しか撮れないんだろうと悩んでいました。 三脚にレリーズを使ってもどうも今ひとつということが多かったです。 単焦点を１本買ってようやく手持ちでもキリッとした人物写真は撮れるようになりましたが、お客さんが忙しいのにレンズ交換でジタバタしているわけにもいきません。ほんとうは画質に優れたSONY RX100ですべて済ませたいのですが、コンデジだと撮影料金を乗せずらいのです。 そんな悩みを解決してくれたコスパ最高のレンズです。 PENTAX用は手ぶれ補正機能がありません。 前ピン気味だったのでカメラで補正登録して使っています。 良い点の感想--------------------- ・広角からズームまで全域でキリッと撮れる。 ・持っていくのがこの1本で済む。 ・AFが静かで早い。 ・開放がしっかりボケる。 ・対象にかなり寄れる(30cmくらい)。 ・色味がクールで調整しやすい。 ・花形フードとキャップ付き。 ・値段が安い。 ・大きいので見た目のインパクトあり。 悪い点の感想--------------------- ・AFがはずれる時がある、特に広角。 ・F2.8はピントに気を使う。 ・やや重い。 ・周辺の光量不足や色収差はとくに広角側である。 対策--------------------- ・ピントを置くときにはっきりした対象を選ぶ。 ・広角側はズームでピントを合わせてから広角にするとほぼ確実。 ・失敗したくないときはF5.6だとシャープ。 SIGMAはサポートが良いとのことですので、調整等してもらうと良いみたいですが、なにせコスパ重視で買ったので、AFの癖に注意しながら使っています。周辺光量不足や色収差は気にしたことはありませんが、平坦な構図だとLightroomで補正することがあります。 このレンズのおかげで撮影したものをPCで見てがっかりすることがなくなりました。 PENTAX用はAFがとっても静かで早いです。他のレンズではジージーいうのが普通だと思っていましたが、クッ、ピッと軽快です。ただしクックックッと迷うことがあるのでそういうときは注意が必要です。 カメラにそれほどお金をかけたくないけど一眼レフらしい画質で撮りたい、撮影知識はちょっとあるという方は鉄板の1本かもしれません。

Nothing to say about the sailor, only about this lens. It is not fully compatible with my Pentax K5 camera. Sometimes, it give me a wrong exposition reading, often over exposed. (compare with my unfortunately dead Pentax 16-50 F2.8. But it is personal opinion.