Exposure & Metering
60 terms · page 1 of 3
Aperture
The adjustable opening inside a lens that controls how much light passes through to the sensor, and with it the depth of field.
Exposure & MeteringAperture Priority
A semi-automatic mode, marked A or Av, in which the photographer sets aperture and ISO while the camera chooses shutter speed.
Exposure & MeteringAuto Exposure Bracketing (AEB)
Shooting a rapid sequence of frames at different exposures around the metered value, as insurance or as source material for merging.
Exposure & MeteringAuto Exposure Lock (AE-L)
A control that freezes the metered exposure so the frame can be recomposed without the reading changing.
Exposure & MeteringAuto ISO
A camera mode that lets the body select sensitivity automatically within limits the photographer sets, usually with a minimum shutter speed.
Exposure & MeteringBase ISO
The sensitivity at which a sensor is read out with no amplification, delivering its maximum dynamic range and cleanest files.
Exposure & MeteringBellows Extension Factor
The extra exposure required when a lens is racked far forward for close focus, spreading its light over a greater distance.
Exposure & MeteringBlown Highlights
Bright areas recorded at maximum value across all channels, rendering as featureless white that no processing can restore.
Exposure & MeteringBulb Mode
A shutter setting, marked B, that keeps the shutter open for as long as the release is held down.
Exposure & MeteringCentre-weighted Average Metering
A metering pattern that averages the whole frame while giving most of the weight — typically 60 to 80 per cent — to the central area.
Exposure & MeteringClipping
The loss of tonal information when values are pushed past the maximum or minimum a file can encode.
Exposure & MeteringCrushed Blacks
Shadow areas pushed to pure black so that separation between dark tones is lost.
Exposure & MeteringDynamic Range
The span between the brightest and darkest tones a camera can record in a single frame while keeping usable detail at both ends.
Exposure & MeteringEffective Aperture
The working f-number of a lens once it is focused close, which is always darker than the marked aperture because the lens is extended away…
Exposure & MeteringEquivalent Exposure
Any different combination of aperture, shutter speed and ISO that yields identical image brightness.
Exposure & MeteringEvaluative (Matrix) Metering
A metering pattern that divides the frame into zones, compares their brightness against a database of scene types, and infers the…
Exposure & MeteringExposing to the Right (ETTR)
The technique of exposing as brightly as possible without clipping, then darkening in processing to maximise signal-to-noise ratio.
Exposure & MeteringExposure
The total amount of light that reaches the sensor or film, set by the combination of aperture, shutter speed and the scene's brightness.
Exposure & MeteringExposure Compensation
A deliberate offset applied to the camera's metered reading, expressed in stops, to make an image brighter or darker than the meter…
Exposure & MeteringExposure Latitude
How far an exposure can miss the ideal and still produce an acceptable image after processing.
Exposure & MeteringExposure Simulation
A live-view or electronic-viewfinder mode that displays the scene at the brightness the current settings will actually record.
Exposure & MeteringExposure Triangle
The teaching model that links aperture, shutter speed and ISO as three interdependent controls, where changing one requires compensating…
Exposure & MeteringExposure Value (EV)
A single number describing every combination of aperture and shutter speed that produces the same exposure.
Exposure & MeteringExtended ISO
ISO settings outside a sensor's native range, marked with an L or H prefix, that are produced by digital manipulation rather than analogue…