照明是每单位区域表面上的总发光通量。它以Lux（LX）为单位。
1 fc = 0.001 ph
1 ph = 929.023 fc
例子:
将15 footcandle转换为光：
15 fc = 0.016 ph
| footcandle | 光 |
|---|---|
| 0.01 fc | 1.0764e-5 ph |
| 0.1 fc | 0 ph |
| 1 fc | 0.001 ph |
| 2 fc | 0.002 ph |
| 3 fc | 0.003 ph |
| 5 fc | 0.005 ph |
| 10 fc | 0.011 ph |
| 20 fc | 0.022 ph |
| 30 fc | 0.032 ph |
| 40 fc | 0.043 ph |
| 50 fc | 0.054 ph |
| 60 fc | 0.065 ph |
| 70 fc | 0.075 ph |
| 80 fc | 0.086 ph |
| 90 fc | 0.097 ph |
| 100 fc | 0.108 ph |
| 250 fc | 0.269 ph |
| 500 fc | 0.538 ph |
| 750 fc | 0.807 ph |
| 1000 fc | 1.076 ph |
| 10000 fc | 10.764 ph |
| 100000 fc | 107.64 ph |
规则