I learned first-hand on Monday why photographers pay dearly for "fast" lenses (large maximum aperture, e.g., f/1.2): even in bright sunlight I found it nearly impossible to successfully photograph the dozen or so hummingbirds buzzing around my friend's feeder. Of the nearly 150 images I shot maybe a dozen came out okay, and only a few really capture the essence of these feisty little guys. I have an all-purpose zoom with a maximum aperture of f/4 to f5.6 (depending on zoom level), and that just won't let in enough light for me to speed up the shutter enough to stop-motion these birds' hard-working wings. Lucky for me I find the blur compelling because it strongly suggests the motion... I was, in any case, pleased to get any decent shots at all because these birds are just so much fun to watch but also so beautiful to behold. I'll miss them when they leave next month.