Thank you for the thoughtful critique. There is indeed some "blur" of the wingtips of the bird on the right, but it has nothing to do with depth of field or the lack of a tripod (camera shake) - it is motion blur of the subject. The bird was travelling at very high speed and also rapidly beating its wings at the time the frame was exposed. With this combination of circumstances, 1/1250 second is not enough to completely freeze all movement. However, I feel that some motion blur of the wingtips of a "bird in flight" shot often improves the image by conveying a sense of motion. I may post another image to illustrate this in the near future.
Best wishes, Nigel.
Peregrine Falcon - Father and Daughter (22)