Excerpt: Image quality is overall very good, as good as the best lenses just a generation ago, and, as I recall, some excellent photos were taken in the 20th Century. Inexpensive, rugged, lightweight. Works only on crop sensor cameras (such as APS-C sensors). Image quality not as good as with a $2000 big white Canon, and if you've purchased a Canon 7D ii body for $1900, you probably wouldn't use it except as a walking around all-purpose lens.
Excerpt: I use this lens with my Canon 7D and have also used in on my older Digital Rebel. It is a good all around lens, I have had trouble getting it to focus when my battery is getting low & sometimes in low light. It also doesn't do great on lots of movement from "little subjects" I have gotten blurred body parts if they are moving too much & depending on the light in the room sometimes it it difficult to shoot in Manual mode.
Pros: Consistent Output, Durable, Strong Construction
Excerpt: I find this to be an optically excellent lens.It (or the camera, or both?) is a bit slow in Auto Focus. Focus: it's difficult to see the reference points (camera, lens, both?). I'm new to SLR's and probably shouldn't have chosen a zoom lens because of severe Image Steadiness problems (mine, not the lens), but this lens is simply TOO BLOODY HEAVY. I'm going to purchase a 40mm to see what that'll do. If necessary, I'll try a shoulder stock.
Pros: Consistent Output, Rugged, Strong Construction
Excerpt: I use this lens on my Canon 70D, and I love it. I work for a company and run their photo shoots, and this lens helps me on the job because of its great versatility. It does a great job at taking macro photos, and is great for nature and landscape photography. It truly is a very multipurpose lens that works great for all types of photography.
Pros: Durable, Easily Interchangeable, Fast / accurate auto-focus, Great macro, Lightweight
Summary: A very good "walk around" lens. Seems to have some problems autofocusing on moving objects. So, not your best choice to shoot something like a Nascar race. But an excellent choice to take with you on vacation.
Excerpt: Excellent price! I bought this just for my Blackmagic Cinema Camera, and it works great! Some lenses don't work well, like the Canon 70-200 F4 L- the iris controls don't work for some reason. This Sigma's iris works well, but the IS does not. Oh well. Image seems good enough, sharp. Ergonomics and build quality are above average. I wish the focus ring turned further for easier manual use.