Nikon D800, Nikon 70-200mm F2.8 with 1.4X teleconverter, ISO 280, F5.6, 1/750 of a second, focal length 280. I finally got him isolated, however, sitting at the bird feeder.
Nice details on this beautiful humming bird, well exposed, and despite the bright area you have a good BG. The biggest issues are the perch and the head angled away. I'd also bump up the ISO for bird photography...you never know when you'll need the extra shutter speed.
Wonderful details, colors and sharpness on your bird. Agree with Daniel there is rarely a reason to shoot with such a low ISO. On the Canon 1D4, my standard ISO is 800 and it helps to be ready for action. Even though your ISO was low here, I am wondering whether you originally underexposed this image since I am seeing quite a bit of noise in your BG.
Very nice! It's often possible to catch them "in flight" as they feed and then back away from the "flower" momentarily -- checking for competitors, I guess. They are usually still long enough to get good focus. You'll miss a lot with odd wing positions but you'll get a few in a session that are good.