I have the Tamron 18-250 lens that you mentioned and I think it is a very good lens for the price. But as others have mentioned before it is not a fixed aperature lens so you will be limited on the types of shots you can get with it especially at the long end. Optically the lens is pretty good for the price and considering the large range that the lens covers. If you are looking for a lens that lets you shoot in many different lighting situations then I would probabbly go with a different lens. Perhaps the tamron 28-75 f2.8 which is about the same price range and while it does not zoom as wide or as long is a much better lens for shooting in different lighting situations.
__________________
Rex K
The view from my "office" doesn't suck. 
|