1/2ステップと1/3ステップのISO感度表を作ってみました。
| ISO100からの段数 | 1/2段ステップ ISO | 1/3段ステップ ISO |
| −2 | 25 | 25 |
| −1 2/3 | — | 32 |
| −1 1/2 | 35 | — |
| −1 1/3 | — | 40 |
| −1 | 50 | 50 |
| −2/3 | — | 64 |
| −1/2 | 70 | — |
| −1/3 | — | 80 |
| 0 | 100 | 100 |
| 1/3 | — | 125 |
| 1/2 | 140 | — |
| 2/3 | — | 160 |
| 1 | 200 | 200 |
| 1 1/3 | — | 250 |
| 1 1/2 | 280 | — |
| 1 2/3 | — | 320 |
| 2 | 400 | 400 |
| 2 1/3 | — | 500 |
| 2 1/2 | 560 | — |
| 2 2/3 | — | 640 |
| 3 | 800 | 800 |
| 3 1/3 | — | 1000 |
| 3 1/2 | 1100 | — |
| 3 2/3 | — | 1250 |
| 4 | 1600 | 1600 |
| 4 1/3 | — | 2000 |
| 4 1/2 | 2200 | — |
| 4 2/3 | — | 2500 |
| 5 | 3200 | 3200 |
| 5 1/3 | — | 4000 |
| 5 1/2 | 4500 | — |
| 5 2/3 | — | 5000 |
| 6 | 6400 | 6400 |
| 6 1/3 | — | 8000 |
| 6 1/2 | 9000 | — |
| 6 2/3 | — | 10000 |
| 7 | 12800 | 12800 |
| 7 1/3 | — | 16000 |
| 7 1/2 | 18000 | — |
| 7 2/3 | — | 20000 |
| 8 | 25600 | 25600 |
| 8 1/3 | — | 32000 |
| 8 1/2 | 36000 | — |
| 8 2/3 | — | 40000 |
| 9 | 51200 | 51200 |
| 9 1/3 | — | 64000 |
| 9 1/2 | 72000 | — |
| 9 2/3 | — | 80000 |
| 10 | 102400 | 102400 |
| 10 1/3 | — | 128000 |
| 10 1/2 | 144000 | — |
| 10 2/3 | — | 160000 |
| 11 | 204800 | 204800 |
| 11 1/3 | — | 256000 |
| 11 1/2 | 288000 | — |
| 11 2/3 | — | 320000 |
| 12 | 409600 | 409600 |
