Summary: I've owned the Tamron 200-500mm telephoto lens since 2010 and have used it several times at a zoo or landscape shots. Last night I used it for my grandson's baseball game on my Nikon D800 and was very impressed with how fast it focused which I thought was as fast, if not faster, than the Nikon...
Summary: At first i was disappointed that focus was more soft than expected at the extremes of zoom (200to 230. And 475-500) HOWEVER.. Between 240mm and 470mm of zoom it is one the finest pieces of glass in my lens stable!
Summary: I knew this when I bought it. I use it for getting the shot of dogs running Lure Coursing which is an outside event. I have several Tamron lens. I love the old ones best they seem more compatable with Canon bodies I have. Also they seem clearer and better lens in general.
Summary: Good response when focusing, needs plenty of light, you will need a tripod to use in wildlife. I am not super happy with it but I can't afford the Nikon product. The Tamron does the job, I am not happy since I do wildlife photography and not good when birds are in motion.
Summary: This lens is worth what they ask for it. That is, it does not compare with the sharpness one would expect from a brand Nikon lens but the picture quality is fair. Don't expect too much bokeh or low-light capabilities. For shooting outdoors at reasonable speeds, this is a great lens.
Summary: I'm sure one of the Canon big lenses would be sharper and faster, but this one isn't a bad lens at all. I will try, but not recommend it, with a 1.4x extender. So far, the 500mm photos do seem a little soft. But if you have your f/7 to 8 in daylight you should be good. No IS?
Tamron AF 200-500mm on Sony DSLR-A900 With Aperture
T. Latham, Amazon
14 April 2010
Summary: I found the lens very light and easy to use in the field for Nature photography, especially birding. I'm getting excellent pictures although the auto-focus feature tends to search a little longer and with pin point focus it tends not to be so precise in those tight bird shots with many leaves.