f-numbers
Below is a table to convert f-numbers described as a stop plus some
number of tenths-of-a-stop into a decimal f-number. I created this
table so that I could conveniently read off guide numbers from my
flash meter which reads out in stops+tenths.
| | +1/10 | +2/10 | +3/10 | +4/10 | +5/10 | +6/10 | +7/10 | +8/10 | +9/10 |
| |
| f 1.00 | 1.04 | 1.07 | 1.11 | 1.15 | 1.19 | 1.23 | 1.27 | 1.32 | 1.37 |
| f 1.41 | 1.46 | 1.52 | 1.57 | 1.62 | 1.68 | 1.74 | 1.80 | 1.87 | 1.93 |
| f 2.00 | 2.07 | 2.14 | 2.22 | 2.30 | 2.38 | 2.46 | 2.55 | 2.64 | 2.73 |
| f 2.83 | 2.93 | 3.03 | 3.14 | 3.25 | 3.36 | 3.48 | 3.61 | 3.73 | 3.86 |
| f 4.00 | 4.14 | 4.29 | 4.44 | 4.59 | 4.76 | 4.92 | 5.10 | 5.28 | 5.46 |
| f 5.66 | 5.86 | 6.06 | 6.28 | 6.50 | 6.73 | 6.96 | 7.21 | 7.46 | 7.73 |
| f 8.00 | 8.28 | 8.57 | 8.88 | 9.19 | 9.51 | 9.85 | 10.20 | 10.56 | 10.93 |
| f 11.31 | 11.71 | 12.13 | 12.55 | 13.00 | 13.45 | 13.93 | 14.42 | 14.93 | 15.45 |
| f 16.00 | 16.56 | 17.15 | 17.75 | 18.38 | 19.03 | 19.70 | 20.39 | 21.11 | 21.86 |
| f 22.63 | 23.43 | 24.25 | 25.11 | 25.99 | 26.91 | 27.86 | 28.84 | 29.86 | 30.91 |
| f 32.00 | 33.13 | 34.30 | 35.51 | 36.76 | 38.05 | 39.40 | 40.79 | 42.22 | 43.71 |
| f 45.25 | 46.85 | 48.50 | 50.21 | 51.98 | 53.82 | 55.72 | 57.68 | 59.71 | 61.82 |
| f 64.00 | 66.26 | 68.59 | 71.01 | 73.52 | 76.11 | 78.79 | 81.57 | 84.45 | 87.43 |
Written by Simeon Warner
This page last updated 14 February 1998