exposureValue

Exposure value, the photographer's single number for a shot's brightness.

log₂(N²/t) − log₂(ISO/100): EV 8.9 at f/2.8, 1/60 s and ISO 100. The adaptation loop and the Direct/Composite modes in docs/design/art.md are what eventually spend it; it is derived here so that when they arrive there is one place the exposure comes from rather than a second, disagreeing one.

lensLens

Undocumented