Greetings, I'm a very uninitiated hobbyist and got this lens used to try to photograph birds. I know, a long lens would probably work better, but I currently get by on limited funds, so this was the best I could do. The reason for the post is that the lens works fine overall, but there are times I shoot a picture and the result seems blurred. I know my lack of experience and technique is primarily to blame, but when I depress the shutter button, the red target thing in the viewfinder usually indicates a focused frame. I've started to wonder if the lens maybe needs some kind of work? It's seems in pretty good shape, the motor for the auto focus works from what I can tell. However, the business end, where the fine focus is, seems be sort of loose, for lack of a better term, if I hold it and try to shift it a little bit. I'm not trying to pry it apart, applying a lot of force, as if trying to pull it loose or anything, I know I should try to leave the lens in one piece as much as possible. Having noticed this though, and not having experience with zooms lenses beyond my own, I don't know how much play is normal between the end with the glass and the housing. Do lenses such as this one need occasional maintenance? I keep the lens on the camera, in the bag, it's a snug fit, but they work together. If more information is needed, please let me know.