Design Nomenclature / Light & Optics
Dynamic range
Also called latitude, stops of range
- Light & Optics
- Systems & Spec
- 2D & 3D
The ratio between the largest and smallest luminance a scene, sensor, or display can carry, usually quoted in stops of doubling. A real scene may span twenty; a good sensor fourteen; an SDR display under ten. Everything difficult about photography lives in that gap.
Not to be confused with
- HDRAs imaging, storing luminance in floating point so nothing clips. As a display standard, a higher peak luminance, a perceptual transfer function — PQ or HLG — in place of a gamma curve, and a wider gamut, with values carried in absolute nits rather than relative to a reference white.
- Tone mappingThe transform fitting a scene's luminance range into what a display can show — compressing highlights, holding mid-tone contrast, and deciding where things clip. It is neither a colour correction nor optional: some curve is always applied, and choosing none means choosing a hard clip.
- ExposureStrictly, the illuminance on the sensor multiplied by the time it is collected — lux-seconds, set by aperture and shutter alone. It determines how much light was actually recorded; ISO merely scales what gets done with the result afterwards.