Apostilb to Lumen per Square Foot Steradian Conversion

Convert between Apostilb and Lumen per Square Foot Steradian quickly and accurately.

From Apostilb

asb

To Lumen per Square Foot Steradian

lm/(ft²·sr)

How to Convert Apostilb to Lumen per Square Foot Steradian

Conversion Formula

1 asb = 0.03 lm/(ft²·sr)

1 lm/(ft²·sr) = 33.816 asb

Example

Convert 15 asb to lm/(ft²·sr):

15 asb = 15 × 0.03 lm/(ft²·sr) = 0.444 lm/(ft²·sr)

Unit Information

Learn about the luminance units you're converting between

Apostilb

asb

Definition

The Apostilb is a non-SI unit of luminance equal to 0.3183098862 candela per square meter. It is used in some specialized applications and provides an alternative way to express low luminance values in certain technical contexts.

History/Origin

This unit was developed as part of early photometric systems and is still used in some specialized applications. It provides a convenient way to express low luminance values and is occasionally found in technical specifications and measurement systems.

Current Use

Used in specialized photometric applications and certain technical contexts where traditional units are preferred. Occasionally found in older technical specifications and specialized measurement systems where non-SI units are still used.

Multiplier

0.318

Offset

Lumen per Square Foot Steradian

lm/(ft²·sr)

Definition

The Lumen per Square Foot Steradian is an imperial unit of luminance that shows the relationship between luminous flux, area, and solid angle using square feet. It is equivalent to 10.7639104167 candela per square meter.

History/Origin

This unit was developed for use in countries employing imperial measurements, providing a way to express luminance in terms of square feet while maintaining the relationship to luminous flux and solid angle. It bridges metric and imperial systems in lighting applications.

Current Use

Used in lighting design and engineering in countries using imperial units, particularly in architectural lighting and display specifications. Common in applications where square footage is the standard area measurement and precise luminance control is required.

Multiplier

10.764

Offset