Sigma 17-70mm f/2.8-4 DC Macro OS (Optical Stabilizer) HSM Lens for Canon EOS Cameras

I've had this lens for about 2 months. I have a Canon Rebel XT with the older 18-55 II non IS lens. It was nearly impossible to get good pictures of my kids unless we were outside in good light. Now, that's not as much of a problem. The wider aperture allows much more light to hit the sensor giving me more keepers. The macro abilities are much better as well. With the 70mm zoom and the close focus distance, I can get great pictures of flowers and such. It's not close enough for shots of insects, but bees and dragonflies will work, if they sit still long enough. Before the 18-55 was a limiting factor in my pictures, now the Rebel is. With the older 8 megapixel sensor, it is easy to get sharp pictures right down to the pixel level. The ability to use faster shutter speeds and the addition of the OS on this lens helps. If you have the newer 18-55 is II lens, I don't know how much of an upgrade this is. But for someone like me that is still living in the dark ages of dslr photography (and will be for a while) this is a worthy upgrade. I'm not getting great vibrant colors with it, but I never did with my 18-55 either. I don't know it it's the camera, lens or just me.Pros:Feels durable/solidOS works well. Took a hand held one second shot while braced. Couldn't blow the picture up, but works for sharing.Zoom and focus rings work smooth.Image quality is great. I've had a lot of positive comments about the pictures I've taken with it.Front element does not turn during focus. Great for polerizers and gradient filters.Much improved auto focus ability over 18-55Wider aperture allows for a brighter viewfinder. Better for composing shots in lower light.Cons:Much heaver then the non IS version of the 18-55. Not sure about the newer ones.Focus ring is right next to the zoom ring, and turns during auto focus. I had to adjust how I hold my camera.No full time focus. I have to switch to manual to adjust focus.AF/Manual focus switch is a little hard to move, could be a good thing, and I may get used to it.Lens cap doesn't snap on tightly, I have to snap it on, then screw it tight.The cons are a bit more nit picky then anything really. For anyone with an older 18-55 looking for an upgrade, this is a great choice. I can't compare this to the 18-55 IS II lens however. There are plenty of reviews comparing to other lenses. For the money, this seems like a good bet.

If there was only one lens I could chose to bring along with me anywhere, it would be this Sigma 17-70mm without a doubt!I rarely have a specific photo shoot in mind when I go anywhere. So usually I would bring two or three lenses with me just to cover all the focal lengths. But that obviously gets bulky and heavy pretty quick. This lens covers wide-angle at 17mm with f/2.8 all the way to medium/telephoto at 70mm with f/4. With that range, I don’t even need to bring anything else with me on a daily basis which is a huge deal!It’s a fast lens that still stops down enough to photograph silky waterfalls with slower shutter speeds. At the larger apertures, the out of focus areas (bokeh) are not super smooth, but still look great and not at all a deal breaker. Like other Sigmas, it’s also not as sharp at larger apertures, but still not a deal breaker.The autofocus is fast and accurate! The motor makes just a little bit of noise, but I hardly ever notice it. I enjoy photographing motocross races which are very fast paced. With the continuous autofocus set, it tracks the racers no problem. The optical stabilization also comes in handy during the races. I’m able to get blurred action shots with the racers perfectly sharp.With all the great features of the Sigma 17-70mm, coupled with the unbeatable price, it’s the perfect lens for the photography enthusiast that wants to bring versatility and range to their run-and-gun setup, but not break the bank.

This review is for the nikon version of the sigma lens. It is great lens, very sharp, great colors, and can focus very closely. I used to have a sigma 105mm macro lens more than ten years ago that I sold together with all my Canon film camera stuff. That was the lens that I loved most among all the Canon lens (including 4 prime lenses). I had so much respect for sigma lens. I saw the good reviews about the "new" version of the sigma lens and bought it from amazon. It is really awesome. One big bonus is the macro photography. This one really focus very close. It does not give you 1:1 macro as the prime macro does, but the focus is close enough for, imo, 90% of the scenarios for macro shots. Focusing is fast. The lens feel very solid. The zooming direction is opposite to nikon zoom lens. Not a big deal hear.There are two things I really wish for. First, the lens barrel is about 65mm I think but the front element is big and it takes 72mm filter. High quality 72mm filters are expensive. Second, I really really wish the zoom range to be extend to around 100mm. It can be a lens like 17-105mm f/4 lens and that would be perfect. I don't mind sacrificing the f2.8 aperture in the front end to trade for a longer zoom if that is possible. The 70mm is better than the zoom range in most 18-55mm either kit lens or f2.8 lens, but still not long enough. So I have to keep two lenses when traveling, this one and the nikon 55-300 zoom lens (a great lens also).If the zoom range is 17-105mm, That would be perfect and I only need to take one lens.I have 2 nikon bodies and about 10 nikon lenses. It is definitely sharper and better than the 18-105mm nikon zoom lens. I hesitated a long time between this one and the tamron 28-75 f2.8 lens. The tamron lens is a great lens also but it is just not wide enough. The lens actually is short and balances very well even on d3100 body. I took some testing short and found the sharpness comparable to the 35mm f1.8 and 50mm f1.8 nikon prime lens. If you look very closely at pictures at pixel level, you may see prime lens slight better but the difference is very small.One point deduct for sigma not making the front element smaller like 62 or 67mm size.Update 12/27/13. After a trip to Orlando, I reviewed the hundreds of pictures I took. I am still very satisfied with the lens. The only issue I noticed was the barrel distortion at the wide angle. I have to correct a couple of photos with software. In some occasions I still miss the 70-105 mm zoom range that I lost with the Nikon lens.