When photographing candid shots of my children at play with a Nikon D90, I have trouble with the autofocus system. I focus and shoot one shot, great. But a second later another shot opportunity opens up, and I waste it because when I press the shutter the camera won't fire, even though I think the focus is fine. The AF system seems to want me to go through the whole press the shutter halfway process.
Am I missing something about using the autofocus system? Usually the lens is set to M/A, and the autofocus mode is AF-A. I've wondered if I should just switch to all-manual focus for situations like this.