Exposure range
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In photography, exposure range is one of several types of dynamic range:
- The Light sensitivity range of photographic film, paper, or digital camera sensors.
- The luminosity range of a scene being photographed.
- The opacity range of developed film images
- The reflectance range of images on photographic papers.
The exposure range of a device is usually expressed in stops, which are equivalent to log2(c) where c is the medium or device's contrast ratio. For example, average Digital Video (DV) has a contrast ratio of 45:1, so its exposure range is roughly 5.5 stops. Film has an exposure range of approximately 14 stops, currently the highest in motion picture mediums.
Exposure is usually controlled by changing the lens aperture (the amount of light it gathers), the shutter speed (how long light is gathered) or sensitivity (how strongly the film or sensor ) responds to light.
A graduated neutral density filter can be also used to improve the reproduction of the exposure range of the scene, by darkening bright parts of the image.
Changing Exposure does not change the Exposure Range, although increasing sensitivity of film or digital cameras will reduce Exposure Range.
