[Des]

One thing to add to the last post. The samples posted might create the impression that there isn't a lot of difference between the cheap lenses and more expensive ones. That impression is misleading. There are two things to bear in mind here. In the first place, down-sizing for web publication reduces the differences. Viewed at larger sizes, the differences are much more obvious. You see it when cropping - I can't crop nearly as much with the 55-300 as with the FA*300 f4.5 most of the time, because the shortcomings become more apparent. Second, the differences in image quality from different lenses is less obvious when shooting in ideal conditions. A consumer zoom can resolve quite well at 1/640th, f8 and ISO 100 (as the samples of the whale, the heron in flight, and the fantail illustrate). But if you have to shoot at f5.8 or f6.3, with higher ISO value, there is a huge difference with a better lens.