Hi, I am just playing around with the video mode casually. Do any cameras esp the smaller mirrorless cameras that continuously autofocus? I just have my D600 which I use it mostly for still photo's, after a few years it's my first time using video on it. With casual video work, any that continually autofocus because when the person walks around then they are out of focus right or if a person holds a piece of paper in front of the camera. Do we always have to press the focus button or manually focus the lens. Thanks.