- Fnumber| f-number| f-number of the capture device.
- A series of f-numbers are so chosen so that the amount of light passed by the lens when set to one number is half that passed by the lens when set to the previous numbers.each f-number is known as a "f-stop".
- "The diameter of such an opening often expressed as an f-number."
- The diameter of such an opening often expressed as an f-number.
- The f-number standard for concrete floor developed by american concrete inst.and canadian standards asoc.