Convert Lux to Phot
Convert lux to phots by entering a value below.
How to Convert Lux to Phots
The lux and phot are both units of illuminance. By definition, 1 phot equals exactly 10000 lux. This means to convert lux to phots, you divide by 10000.
Formula
Step-by-Step Example
Convert 5 lx to phots:
We need to convert lux to phots
Since 1 ph = 10000 lx, divide by 10000
5 ÷ 10000 = 0.0005
5 lx = 0.0005 ph
Lux to Phot Conversion Table
Quick reference table for common lux to phot conversions. Click any value for detailed calculation.
| Lux (lx) | Phots (ph) |
|---|---|
| 0.1 lx | 1e-5 ph |
| 0.5 lx | 5e-5 ph |
| 1 lx | 0.0001 ph |
| 2 lx | 0.0002 ph |
| 5 lx | 0.0005 ph |
| 10 lx | 0.001 ph |
| 25 lx | 0.0025 ph |
| 50 lx | 0.005 ph |
| 100 lx | 0.01 ph |
About These Units
Lux (lx)
The lux (lx) is the SI unit of illuminance, measuring luminous flux per area (lumens per square meter). Typical values: moonlight 0.1 lx, office 300-500 lx, overcast day 1,000 lx, operating room 10,000 lx, direct sunlight 100,000 lx. Used in lighting design, photography, and workplace safety standards.
Phot (ph)
The phot (ph) is the CGS unit of illuminance equal to 10,000 lux or 1 lumen per square centimeter. Very bright: full sunlight is about 10 phots. Found in older scientific literature. One phot = 929 foot-candles. Largely replaced by lux in modern usage.
Frequently Asked Questions
How do I convert lux to phots?
To convert lux to phots, divide the value by 10000. For example, 10 lx = 0.001 ph.
How many phots are in 1 lux?
1 lux equals 0.0001 phots.
What is the formula for lux to phots?
The formula is: ph = lx ÷ 10000.