Excerpt: Having recently acquired this lens, I proceeded to make several test shots with it and then took it out on a shoot mounted on a 5D Mk III body.<br />The lens is fairly compact and hand-holdable for its focal length range, and the stabilizer is a major asset. The autofocus is fast, quiet and accurate, rendering crisp and sharp images throughout the zoom range.
Pros: Consistent Output, Fast / accurate auto-focus, Rugged, Strong Construction
Summary: I bought this to replace the Canon 70-300 (non-L) lens I already owned, looking for better sharpness particularly at the 300mm end. Image sharpness was superb at 300mm, even wide open, and much better than the older 70-300, (which was actually a pretty good lens.) I also appreciate the non-rotating front elementd, which makes it easier to use a polarizer. I took away a star for two reasons. First, a tripod collar was not included.
Conclusion: The lens is doing a great job. i have been using it for the last two weeks and will still need more time to give a better review. So far so good and it does a better job then the previous lens i had.
Excerpt: I purchased this lens after trying the 100-400 L. Like the 100-400, this lens has serious heft but is much easier to shoot hand held.<br />After a couple of weeks of shooting a wide variety of subjects in varying light conditions, this lens is a keeper. If you're looking to shoot in low, light hand held, you'll be disappointed. The lens is soft wide open, period. I knew that going in so I wasn't surprised. Take this baby outdoors, stop it down to f7> and fire away.
Pros: Durable, Easily Interchangeable, Fast / accurate auto-focus, Rugged, Strong Construction
Excerpt: I have the 70-200 f4IS, 70-200 f 2.8 IS II and the 100-400 in addition to this lens. The lens has the L construction. it is short and stout. has a fast silent focusing, and is optically very good. The lens may make sense on an apsc, where the fov goes to 480, and can be used as a wildlife lens. on full frame, I felt that if 200 was not enough, I usually want 400.
Pros: Consistent Output, Fast / accurate auto-focus, Strong Construction
Cons: Ballance On Camera, Extends while zooming, Variable Aperture
Excerpt: I bought this lens to replace my 70-200 f/4L IS because I wanted the longer reach. This lens is bulkier and heavier and I don't think is quite as sharp (the 70-200 f/4L IS was an outstanding lens!). However it is more convenient to use than to have to add a teleconverter to the shorter lens and the picture quality is perfectly acceptable.
Pros: Consistent Output, Easily Interchangeable, Rugged, Strong Construction