Convert Apostilbs to Lamberts (asb to L)
1 apostilb (asb) = 0.0001 lamberts (L). 1 L = 10000 asb. Example: 15 asb = 15 × 0.0001 = 0.0015 L.
Also searched as apostilbs to L, apostilbs in L, apostilbs into lamberts, asb to L, asb in lamberts, asb into lambert, apostilb to lambert, asb to lamberts converter and how many lamberts in an apostilb.
1 asb = 0.0001 L
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk apostilb to lambert converter to paste a column from Excel.
How to Convert Apostilb to Lambert
- 1 asb = 0.0001 L
- 1 L = 10000 asb
- Example: convert 15 asb to L: 15 asb = 15 × 0.0001 L = 0.0015 L
Formula
L = asb ÷ 10000
Derivation from SI units:
- 1 asb = (1/π) cd/m² ≈ 0.3183 cd/m².
- 1 L = (1/π) cd/cm² ≈ 3183 cd/m².
- 1 asb = 0.3183098861838 cd/m² ÷ 3183.098861838 cd/m² per L = 0.0001 L
Both units are defined exactly, so the factor is exact. Apostilb definition: apostilb; Lambert definition: lambert.
Worked examples
- A reading of 31.5 asb converts to 0.00315 L.
31.5 asb × 0.0001 = 0.00315 L - A value of 1000 asb is 0.1 L.
1000 asb × 0.0001 = 0.1 L
Apostilb to Lambert conversion table
| Apostilbs (asb) | Lamberts (L) |
|---|---|
| 1 asb | 0.0001 L |
| 4 asb | 0.0004 L |
| 10 asb | 0.001 L |
| 31.5 asb | 0.00315 L |
| 100 asb | 0.01 L |
| 318 asb | 0.0318 L |
| 1000 asb | 0.1 L |
| 3180 asb | 0.318 L |
| 10000 asb | 1 L |
| 31800 asb | 3.18 L |
Where it's used
Apostilbs are used for ophthalmic perimetry, while lamberts appear in older vision-science literature. Both measure luminance (brightness of a surface or screen), so the conversion is a fixed factor.
Apostilb to other luminance units
| Conversion | 1 asb equals |
|---|---|
| apostilb to lambert | 0.0001 L |
| apostilb to nit | 0.3183098862 cd/m² |
| apostilb to foot-lambert | 0.09290304 fL |
| apostilb to candela per square foot | 0.02957195609 cd/ft² |
| apostilb to candela per square inch | 0.0002053608062 cd/in² |
| apostilb to stilb | 0.00003183098862 sb |
Frequently asked questions
How many lamberts are in 1 apostilb?
1 asb = 0.0001 L.
How do I convert apostilbs to lamberts?
Multiply the value in asb by 0.0001, or divide it by 10000. For example, 15 asb × 0.0001 = 0.0015 L.
Is the asb to L conversion exact?
Yes. Both units are defined exactly, and 1 asb is exactly 0.0001 L.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "apostilb".
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "lambert".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Apostilbs to Lamberts (asb to L). Retrieved October 25, 2026, from https://scientificconverters.com/luminance/apostilbs-to-lamberts/
IEEE
Scientific Converters, "Convert Apostilbs to Lamberts (asb to L)," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/luminance/apostilbs-to-lamberts/