Originally Posted by
Manfred M
Grahame - while the cameras and the settings are a bit different, my D810 appears to behave exactly the way that your D800 does. I have it set to AF-C, single focus point and use BBF. In this mode, it will fire whenever I press the shutter release, regardless of whether or not I have achieved focus lock. In the "default" setting, it will not let me switch to AF-S at all. I have to dive into the menu and over-ride the default and that lets me switch to AF-S.
When I override the default and enable AF-S, the camera will not fire until it gets a focus lock. Unfortunately(?) once the camera focuses and I reframe without hitting the BBF button, the camera will happily assume that nothing has changed and will fire away even if things are now out of focus.