Sigma 10-20mm f/4-5.6 EX DC HSM Lens for Canon Digital SLR Cameras

I'm a nut for wide-angle photography. I don't mean to get technical, but for those who do not know the sticky details, modern Digital SLRs often have sensors that are quite a bit smaller than the traditional exposure area of film: 24mmx36mm. In the case of Nikon DSLRs (all current models except their $5000  Nikon D3 12.1MP FX Digital SLR Camera (Body Only)  professional FX sensor model) use what they call a DX sensor which is 16mmx24mm.For us old film hounds, this means that a lens of a given focal length will roughly translate to 1.5x when switching from film (of Full frame) to DX. So, your old 20mm wide angle lens will "crop" to about the equivalent of a 35mm lens when put on a DX sensor DSLR.For those who really like telephoto shots, this is a positive boon. Your 300mm lens will take pictures that have the same angle of view as a 450mm lens, but for those of us wide-angle freaks, this "digital crop factor" takes some of the "punch" out of the bottom end. Many general-use zooms for the DX sensor cameras start around 18mm. This would be ultra-wide on that old film camera, but it takes pictured that look more like what you'd expect from a 28mm lens on a traditional film camera.Ok, sorry for all the mumbo jumbo, but now on to why this lens is so great...With its 10mm-20mm focal length, this lens is the 35mm film SLR equivalent of a 15mm to 35mm zoom lens, and 15mm full-frame is about the widest you can go before getting into "fish-eye" territory.With this Sigma lens at 10mm, you get a very wide angle perspective without crossing over into fish-eye territory. Yes, there is noticeable "barreling", but nothing beyond the range of most modern photo/image editing software's ability to fix. Frankly, I like a little of that in my ultra-wide photos. At the 20mm end, the "barreling" is much less noticeable.As will all extreme wide angle lenses, if you get right on top of your subject, you'll really amplify the distortion effect, but if you're shooting at 10mm and focusing down to the lenses minimum focus distance (an amazing 10" or so), you're probably already expecting, and even counting on such distortion anyway.Did I mention that it focuses down to around 10"?The construction of this lens is solid, and it has a little heft to it. It comes with its own custom lens hood. USE IT. The front element on this lens bulges out a bit (as you can see from the product photos), and aside from helping with lens flare, that extra bit of "guard rail" will help you avoid scratching the thing. I've put a UV filter on the front to help protect the glass, but the distance between that glass and the front lens element makes this "reflection box" that has visibly shown in some of my highly backlit/highly contrasty photos.The focusing is fast and silent. I really like the fact that this is one of those "internally focusing" lenses which means that the act of focusing does not turn the manual focus rung, and doesn't make the lens change position or size. More importantly, if you want to manually focus, you can just grab the ring and turn because it's not "locked" into place in AF mode like many other lenses.I've taken some of my best photos with this lens, and for the wide-angle enthusiast with a DX sensor Nikon DSLR, I'd go so far as to say this is a must-have. It's got 2mm wider focal length than the nearest Nikon (with DOES make a visible difference at the low-end), but its incredibly well made and clear from edge to edge (though, it does have that "barrel" distortion... it's still crisp from end to end with little to no vignetting)Sorry, I probably went on a bit, but as you can tell, I really like this lens. I'd highly recommend that you do your research before you buy it as ultra-wide angles do have some idiosyncrasies, but if you know what to expect (photographically) from them, then this lens is one of the best I've ever played with/owned.

Sigma 10-20mm f/4-5.6 EX DC HSM Lens for Nikon Digital SLR Cameras If you've never used an ultrawide lens before, you're in for a shock -- and a new challenge. Mount the Sigma (or any other ultrawide) on a DSLR, rack it out to 10-11mm, look through the viewfinder and see an entirely new perspective on the world that is totally different from what the human eye sees. Objects that are close to the camera appear much closer, and distant objects appear to be much farther away. You'll also notice that straight lines toward the edges of the frame bend, and this distortion changes dramatically as you point the camera up or down. It's a whole new world of photography, and making effective use of the ultrawide perspective takes some practice and getting used to.Regarding the Sigma 10-20mm f/4-5.6 specifically, it is arguably the most popular among several ultrawide choices available to Nikon and Canon users for several good reasons -- not the least of which is its low price (I recently purchased one from Amazon for my Nikon D90 for $479.99). Construction quality is excellent, particularly for a third party lens. There's nothing loose or sloppy about it, and it feels solid. I especially like the nonslip exterior finish of the zoom and focus rings, which are large and well-separated. Zooming is a little on the stiff side, but very nicely dampened and smooth without any "catches" in the zoom travel.Optically it's a bit of a compromise, like all ultrawides, but Sigma did a good job of balancing them. Overall sharpness is generally quite good, but it's not absolutely tack-sharp. It's noticeably soft, even in the center, at f/4 (especially zoomed out to 10mm). Stopping down to f/5.6 cures this and improves edge sharpness dramatically. Vignetting is also quite noticeable wide open at 10mm, but stopping down a bit virtually eliminates this problem. Distortion at 10 mm is irregular and difficult to correct in post processing, but simply zooming in to 11mm corrects this problem for architectural shots with a lot of straight lines. Lens flare and chromatic aberration that can be problematic with ultrawides are both extremely well managed -- not a problem at all, in fact.In summary, the Sigma 10-20 is a reasonably priced and incredibly useful addition that will open up new photographic horizons for anyone whose current widest angle lens is 17-18mm. For example, it's a perfect complement to the versatile Nikon 18-200 VR lens for anyone who wants to travel light and still have all their bases covered for any photographic eventuality. Other users have accurately described it as a "fun" lens. And it even comes packaged with a nice padded case. Nice touch, Sigma.

The quality and images are perfect.

写真で見たものより素晴らしくきれいなレンズで感激しました、ありがとうございます。

送られた時にレンズのキャップ無くやっぱりレンズ内の埃が写り込みせめてレンズキャップ無いならラップで巻いて埃が入らない様にするとか、梱包が駄目でした新品同様と書いてましたが全然使い物になりません

Zuikoの7-14mm、9-18mm、11-22mmと迷った末にこっちを購入。中古品でしたがレンズ内部は非常に綺麗で新品同様でした。サブ機のE-500に装着して遊んでいます。屋外で青空を入れると真っ青で綺麗に撮れます。　接写した際の背景の軽いボケも柔らかく滲む感じで好きです。

spedizione veloce, confezione adeguata, ovbiettivo contenuto nella sua custodia.qualità buona; io non sono certo un professionista ma devo dire che le foto sono ottime; provato sia in interno che esterno deforma poco il campo anche alla minima focale. al momento non vedo aspetti negativi

Built quality.....image quality is excellent.