Exposure

Exposure is an image adjustment that multiplies light values to brighten or darken the image. In photographic units, a one-stop increase doubles the light values; a one-stop decrease halves them.

BetterDisplay's stream exposure filter changes captured pixels, rather than camera shutter settings or the monitor's backlight. It differs from gamma, which changes the relationship between darker and lighter tones. Large increases can make highlights clip.

See Video Filters and Stream Transformations and Apple's exposure-filter documentation.