Photometry
Ltoasb
Convert lamberts (L) to apostilbs (asb).
Factor1 L = 10000 asb
Converter
L
Accepts numbers or expressions, e.g. 150 + 14.7
Result
asb
Rendered to 6 significant figures.
Formula
Formula
asb = L × 10000
Multiply any value in lamberts by 10000 to obtain the value in apostilbs.
Worked example
Convert 1 L to asb.
- 01Start with 1 L.
- 02Multiply by the conversion factor: 1 × 10000 = 10000 asb.
Result1 L = 10000 asb
Conversion table
| L | asb |
|---|---|
| 1 | 10000 |
| 2 | 20000 |
| 5 | 50000 |
| 10 | 1.0000e+5 |
| 20 | 2.0000e+5 |
| 50 | 5.0000e+5 |
| 100 | 1.0000e+6 |
| 200 | 2.0000e+6 |
| 500 | 5.0000e+6 |
| 1000 | 1e+7 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from L to asb?
1 L equals 10000 asb. To convert, multiply the value in lamberts by 10000.
How do I convert 1 L to asb?
1 L = 10000 asb. For any value, multiply by 10000.
How do I convert asb back to L?
Divide by the same factor — or equivalently, multiply by 0.0001. So 1 asb = 0.0001 L.
When would I need to convert lambert to apostilb?
Luminance conversions between L and asb are used in display engineering, road and traffic-signal design, and photometric measurement of luminous surfaces. cd/m² (nit) is the SI standard; foot-lambert and stilb appear in legacy datasheets and specialist optics work.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).