I have a technique question , I have a Nikon 70-200 vr (great lens) there are several focus lock button on end of the lens. I have found this easy to use. I have tried to perfect the technique of using the rear focus lock button, but the shutter button on the D7000 is sensitive, and I often miss fire the shot . Today I played with the settings and assigned the rear AF-L button to focus the camera. I was wondering if the rear button will also lock focus ? I took some practice shots and they look good . I am not sure if I was locked or following my subject ? any suggestions?