Luminosity

The amount or quality of light emitted by a source.

Reach for it when discussing brightness scientifically or describing radiant visual presence

Astronomers calculated the star's luminosity from its distance and flux.

• everyday

  brightness

  perceived intensity of light is the plain subject

  not when Brightness is broader and may refer to reflected light.

• professional

  light output

  plain technical wording serves a practical specification

  not when Light output may use several measures and lacks astronomical precision.

• professional

  luminance

  light intensity per apparent area in a direction is technically meant

  not when Luminance is not the same physical quantity as total luminosity.

• literary

  radiance

  the impression of light streaming outward is central

  not when Radiance is descriptive rather than a measurable physical property.

A quality of clear, radiant brightness in art or appearance.

Reach for it when praising a glowing visual effect in elevated criticism

Thin layers of paint gave the portrait unusual luminosity.

• warm

  glow

  soft visible brightness is the artistic effect

  not when Glow can be vague and does not capture overall luminous quality.

• literary

  brilliance

  intense sparkling brightness deserves emphasis

  not when Brilliance is stronger and can imply sharpness rather than soft luminosity.

• dimness
• darkness
• dullness

• stellar luminosity

  Stellar luminosity helps scientists compare stars of different distances.

• apparent luminosity

  Dust reduced the galaxy's apparent luminosity.

• sense of luminosity

  Pale gold created a sense of luminosity around the figures.