Aperture
The auto-aperture of a camera works much the same way as your eye. The human eye's on-the-fly pupil-size adjustment is analogous to the video camera's "auto" aperture.
However, unlike your eye, the aperture of a camcorder can be set manually. That is, you can open and close the camera's "pupil" ( aperture) manually--as little or as much as you like.
Cameras use specific numbers to describe the size of the aperture. These numbers are called f-stops.
It might make sense to number the f-stops 1,2,3,4 etc., but that's not how it works. Instead, the official f-stop numbers don't seem to make any logical sense. Nonetheless, here they are:
The important thing to know that small numbers (2, 2.8 etc) mean big lens openings and big numbers (16,22) mean small openings. So in the illustration below, the far left f-stop is f2.
