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.

I am shocked about this lens. After many visits to the camera store, hours of internet research, and dozens of questions to professionals I bought this lens from Amazon. No local dealers bothered to carry it so once again the sale went to the internet.During my research it became obvious that one of the major limitations of many new DLSR's is a smaller overall field of view when compared to a traditional film based SLR using the same basic lens. Without going into the "why" the bottom line is my Nikon D40X's stock 18-55 cannot capture as wide a shot as I want.Terminology becomes an issue when trying to explain this lens to an amateur, or the person who might be involved with your new 500 dollar purchase. The word "wide" has new meaning these days when applied to TV's and monitors, so people are confused when you try to tell them about a lens that is "wide". This is significant because so many new D40X buyers, for example, are jumping into SLR for the first time and have no clue about lenses. These are the people who probably have no idea what they are missing.The overall focus on lenses gets further confusing for amateurs because of all the hype about "zoom", and when kits like the D40X give you an extra zoom but no wide lens. Zoom is like one of those numbers consumers make sure to ask about before they make their purchase. While zoom photography is cool, I feel the magic of wide-angle photography is a well kept secret. Consumers would be well served to be asking about "wide" instead, and start walking the camera up closer to their subject. You'll see why later.Doing research became even harder when I began to read about the Nikkor 12-24 and new 14 wide angle lenses. At $1000 and $1700 I began to feel like my dream would never come true. Then I held the new 14mm at the camera store, attached to a D60. It is a monster in every way. After looking at some dinky conversion lenses I was ready to give up. The amazing reviews of the new Nikon wide-angle lenses left me feeling it might be years away.That's when I found the Sigma 10-20, roughly 5 lenses later. The solid 5 star reviews combined with under-$500 price tag got me looking, and then the test shots. $20 of overnight shipping later I must say this is a product that should come with the camera. All new consumers should be made aware of what this thing can do. It should be bundled or at least sold beside these cameras, not the total mystery it seems to be. This wide angle lens should go into the hands of amateurs and professionals alike. It could be the factor that keeps new people into the hobby when their zoom shots are all messed up. Simply put this lens allows your camera to better match what you see with your eyes. The creative possibilities of a wider field of view should not be underestimated. It could sell more cameras, so it seems the competition should be looking up to Sigma, especially at this price tag. Have fun!