Ducks make for fun birds-in-flight photos. This lovely lady is heading for the hills.

Canon 7D with 400L 5.6 lens handheld @ 1/1250, f/5.6, ISO 400.

Top and bottom cropped away to frame for a 8 x 16.

As long as the eye is in focus, I'm a happy camper. Some people want the bird's movement to be completely frozen, which is fine. But, I don't mind wing blur - it gives a better sensation of movement.

Cheers,

Mike