Modern lenses use a standard f-stop scale, which is an approximate of the powers of square-root 2:
f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11,f/16, f/22, f/32, f/45, f/64, f/90, f/128, etc. typical one-half-stop f-number scale >
- f/1.0
- f/1.2
- f/1.4
- f /1.7
- f/2
- f/2.4
- f/2.8
- f/3.3
- f/4
- f/4.8
- f/5.6
- f/6.7
- f/8
- f/9.5
- f/11
- f/13
- f/16
- f/19
- f/22
Typical one-third-stop f-number scale
- f/1.0
- f/1.1
- f/1.2
- f/1.4
- f/1.6
- f/1.8
- f/2
- f/2.2
- f/2.5
- f/2.8
- f/3.3
- f/3.5
- f/4
- f/4.5
- f/5.0
- f/5.6
- f/6.3
- f/7.1
- f/8
- f/9
- f/10
- f/11
- f/13
- f/14
- f/16
- f/18
- f/20
- f/22