After last weekends trip to the Philly zoo I realized that some of the pictures were not as sharp as I would have hoped and also I had to crop a lot more than I wanted because I was missing focal length on the upper end. So the quality I refer to in the title is that of the taken photographs. The solution to the problem is a better lens, one with a longer focal lens that is also faster. Before making any decision to buy I have rented one over the long weekend (Monday is Labor Day) and got it on Wednesday. I immediately noticed the difference in weight compared to the other lenses I had until now...To really play around with the lens I spent a few hours in the Bronx Zoo, since that's where a longer focal length would really come in handy. The pictures are great, really a step up from what I was able to get just a week ago but I didn't enjoy having all that weight either around my neck or in my hands all the time. So I'm still not sure if I should consider getting a longer lens or not, hopefully after using it more the next two days I have a better idea. Stay tuned for more pictures...