I'm transitioning to using the AE-L/AF-L button for focusing (by changing Custom Menu Setting 12 to AF-ON), rather than using the shutter release button. The problem is that unless focus is detected, the shutter won't release.
Thom Hogan's guide tells me that if I select Continuous Servo Focus Mode (AF-C). The shutter should release, even if the focus isn't detected. My D40 does not behave this way. It's not that I'm wanting to take out of focus pictures. I just want to re-compose and put the subject in focus somewhere else in the frame.
Is there some other setting that might be interfering with it operating in the way I want? Or am I doing something else wrong? Seems like I've got it stuck on focus priority some way.