Here is some of the Nikon D4 Q/A's
@IR_Lab Nikon D4 Question: Minimum increments of aperture change during video recording?
(Steve Heiner) - For video, this is where the D4 will really impress. When recording to the internal memory cards, the same option to change aperture exists, changing the aperture in 1/3 stop increments. We've added a new feature called Power Aperture, in Live View mode, though: Using the Preview and Fn buttons on the front of the camera, you can smoothly and steplessly open and close the aperture in Live View mode (prior to recording). If you're reco