http://www.nikonchat.com/nikon-d7000-aperture-mode/

How important is the shutter speed for video DSLR? It seems that the only exposure change …?
Shooting in manual mode w / nikon d7000 I can not change the aperture, why? Change the shutter speed does not seem to change the speed of video exposure only. The results have same in 1 / 30 1 / 50 1 / 500 Why?
Because the video only records at 24 fps or 30 fps.
Photography Tutorials FIRST Lesson! What is Aperture or F stop ? Important basic lesson for beginner