Hello, I'm using a D700 and a AF-S Nikkor 300mm f/2.8 ED VR I for night time sports and sometimes when I press the shutter the camera doesn't fire, like it can't focus fast enough. I've tried Dynamic AF Area of 9, 21, and 51. Changed the Focus Tracking with Lock-on from short to long. My AF-C is set to Focus Only, and the Built in AF-Assist illuminator it OFF. Can someone recommend which settings I should use? Thanks.