With the Nikon D600, when shooting in live view you cannot adjust the aperture setting without getting out of live view for each adjustment. My tip is that you can change the brightness or darkness to a picture in live mode by pressing the EV button and rotating the rear command dial. This will work in live view whether you are recording or not. It will also work for still photography. The only drawback is that you will hear the clicks in your video as the command dial turns if you are recording.