Photometry
nttoasb
Convert nits (nt) to apostilbs (asb).
Factor1 nt = 3.141593 asb
Converter
nt
Accepts numbers or expressions, e.g. 150 + 14.7
Result
asb
Rendered to 6 significant figures.
Formula
Formula
asb = nt × 3.141593
Multiply any value in nits by 3.141593 to obtain the value in apostilbs.
Worked example
Convert 100 nt to asb.
- 01Start with 100 nt.
- 02Multiply by the conversion factor: 100 × 3.141593 = 314.159 asb.
Result100 nt = 314.159 asb
Conversion table
| nt | asb |
|---|---|
| 1 | 3.1416 |
| 2 | 6.2832 |
| 5 | 15.708 |
| 10 | 31.416 |
| 20 | 62.832 |
| 50 | 157.08 |
| 100 | 314.16 |
| 200 | 628.32 |
| 500 | 1570.8 |
| 1000 | 3141.6 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from nt to asb?
1 nt equals 3.141593 asb. To convert, multiply the value in nits by 3.141593.
How do I convert 1 nt to asb?
1 nt = 3.14159 asb. For any value, multiply by 3.141593.
How do I convert asb back to nt?
Divide by the same factor — or equivalently, multiply by 0.3183099. So 1 asb = 0.31831 nt.
When would I need to convert nit to apostilb?
Luminance conversions between nt 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).