
Originally Posted by
John 2
Adrian, it's difficult to see what is going on here because this is a very low resolution image but from what I can see it looks like the plane of focus is in front of the bird. Given the limited DOF at 600mm and f6.3, this would be enough to push the bird out of focus. I can't see any evidence of movement (e.g. ghosting). You could probably come down from 1/4000th sec to around 1/1500th -1/2000th sec and drop the aperture to around f8 or f11 to get a greater DOF. The definition of the lens is better at these apertures anyway. Give it a try.