Photography & Imaging

Intermediate

Exposure Value (EV)

Combines aperture and shutter speed into one exposure figure.

Formula

EV = \log_2\!\left(\frac{N^2}{t}\right)

Variables

EVExposure value

NF-number

tShutter time (s)

Example

f/4, 1/60 s: EV = log2(16×60) ≈ 9.9

Did You Know?

EV 0 is defined as f/1.0 at 1 second — every whole EV step up halves the light reaching the sensor.

photography exposure ev

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More in Photography & Imaging

F-Number

Aperture f-number is focal length divided by aperture diameter.

Depth of Field (approx.)

Range of distances that appear acceptably sharp.

Hyperfocal Distance

Focus distance that keeps everything from H/2 to infinity sharp.

Lens Magnification

Image magnification from focal length and subject distance.

Angle of View

Field of view from sensor size and focal length.

Equivalent Focal Length

Focal length on a crop sensor expressed in full-frame terms.