Exposure & Metering
3 terms
F-number
Exposure & Metering
Dimensionless ratio
The ratio of a lens's focal length to the diameter of its entrance pupil, written f/2.8, f/8 and so on, and the standard way of stating aperture.
N = f / D
Filter Factor
Exposure & Metering
stops (EV)
The exposure increase, in stops or as a multiplier, needed to compensate for the light a filter absorbs.
Stops = log₂(factor)
Flicker Reduction
Exposure & Metering
Hz
A camera function that times the shutter release to the peak of a pulsing artificial light source, preventing exposure and colour shifts between frames.
Cycle = 2 × mains frequency