the.com/luminance
how bright something looks, after your eyeballs cast their biased vote on physics
means Luminance is the measurable amount of light a surface emits or reflects toward your eye in a given direction, weighted by how brightness actually registers in human vision.
from From Latin 'lumen,' light — the same glow behind 'illuminate,' 'luminous,' and 'lucid.' The '-ance' suffix turns it into a quantity, a thing you can measure, the way 'distance' measures apart-ness. The technical sense, distinct from plain old 'brightness,' is a 20th-century child of photometry, when scientists needed a word for light measured not as raw physics but as the eye genuinely perceives it.
- unit
- measured in candela per square meter, called nits
- sun surface
- roughly 1.6 billion nits of pure menace
- green bias
- eyes weight green far heavier than red or blue
- HDR screens
- chase 1000+ nits to fake real sunlight
- not brightness
- a physical quantity, while brightness is your brain guessing
sun surface — approximately 1.6 × 10^5 candelas per square meter, brightest natural object visible from earth
full moon — approximately 2,500 candelas per square meter, measurable standard for night sky brightness
white paper under daylight — approximately 3,000-10,000 candelas per square meter depending on illumination angle