exposure

photography

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Last updated

June 26, 2026

Quick Summary

In photography, exposure refers to the total amount of light allowed to fall on the photographic medium (film or sensor). It is determined by a combination of aperture, shutter speed, and film sensitivity (ISO).12

Aperture: The size of the opening in the lens that controls the amount of light entering the camera.2
Shutter Speed: The duration for which the camera's shutter remains open, controlling how long light hits the sensor.2
Film Speed (ISO): Indicates how sensitive the film or sensor is to light.2

An exposure meter is a device that measures light intensity to help photographers determine the correct aperture and shutter speed for proper exposure. Overexposure occurs when too much light reaches the sensor, while underexposure happens when there isn't enough light. Exposure latitude refers to the range of exposures that can still produce an acceptable image.3451

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technology of photography
Basic camera functions
The time of this exposure is one of the two factors controlling the amount of light reaching the film. The other factor is the lens diaphragm, or aperture, an opening with an adjustable diameter. The combination of the diaphragm opening and exposure time is the photographic exposure. To obtain…
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The time of this exposure is one of the two factors controlling the amount of light reaching the film. The other factor is the lens diaphragm, or aperture, an opening with an adjustable diameter. The combination of the diaphragm opening and exposure time is the photographic exposure. To obtain…
Read More

motion-picture camera
… that is repositioned after each exposure. Commonly, exposures are made at the rate of 24 or 30 frames per second on film that is either 8, 16, 35, or 70 mm in width.
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… that is repositioned after each exposure. Commonly, exposures are made at the rate of 24 or 30 frames per second on film that is either 8, 16, 35, or 70 mm in width.
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