On the lens forum I learned from Brian Wong that one can, under F5, look for the aperture control submenu, and this will allow enabling those lenses which have an aperture ring to be used DURING video shooting (& of course, for still as well).
This may be duh news for some, but I have been seeing criticism of the D600's "crippling" of the D800's ability to change aperture while shooting video since it was released.
My suggestion: find a nice used Nikkor 28-70mm f2.8 D AF-S and use its aperture ring to be able to change aperture while shooting. I tried it with a borrowed 50mm with aperture ring and IT WORKS! From what I can learn from other Nikonians, this lens is almost as good quality as the G version (which is excellent), $1000 USD cheaper, and unfortunately, 4mm less wide. BUT, it will fill the bill to allow a workaround for the crippled aperture feature while in video mode. I'm looking now....
The onboard microphone will pick up the noise, just as it does for zooming, and it sounds like someone is crinkling cellophane next to the camera. So, another good reason to get an external microphone.