An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

An exposure obtained with an instrument mounted on the telescope using an artificial illuminating source in order to calibrate the instrument.

→ calibration; → exposure.

Nurdâd, → exposure; kabizeš, → calibration.

A → CCD frame obtained with closed → shutters in the absence of any light source, in order to estimate the → dark current of the → detector.

→ dark; → exposure.

An exposure in which the detector shutter remains open for a relatively long time in order to bring out the weaker features of the observed object. In practice a deep exposure with a CCD detector is usually obtained from co-addition of shorter exposures.

→ deep; → exposure.

1) The act of exposing; the fact or state of being exposed, → expose.
2) In optics, the total radiant energy incident on a surface per unit area. It is equal to the integral over time of the radiant flux density.

Verbal noun of → expose.

In photography, an instrument used to measure the intensity of light from a scene to be photographed and to indicate the camera lens and shutter settings required to expose the film correctly.

→ exposure; → meter.

The length of time during which the receiver is irradiated.

→ exposure; → time.

The division of a relatively long exposure into several successive shorter ones, e.g. to avoid detector saturation.

→ multiple; → exposure.

Excessive exposure of a detector, → over-expose.

→ over-; → exposure.