These are great. Please tell me there is a 10,000:1 delete:keep ratio!I'm not sure about the others, but my ratio isn't that bad! It's really hard to shoot them, though, especially at 360mm / ~1.5-2x (180 macro + 2x extender) like my top photo, which is uncropped. They move fast, are timid and using a tripod is all but useless. I love the challenge of shooting them, but only take their photo if I happen to see one. I've never gone looking for them. The other guys photos are spectacular and I'm guessing they've put a good deal more effort into them and would be curious to hear about how they shoot them.
My keeper rate is decent. Dragonflies return to a specific perch repeatedly. I set up a tripod with a cable release, prefocus, and fire a burst. I didn't shoot any last summer, looking forward to using the 600 II (with a TC and an extension tube for more mag and a closer working distance – 1200mm frames ~4.5x3" at 12').