Bracketing

In photography, bracketing is the general technique of taking several shots of the same subject using different camera settings. Bracketing is useful and often recommended in situations that make it difficult to obtain a satisfactory image with a single shot, especially when a small variation in exposure parameters has a comparatively large effect on the resulting image. Autobracketing is automatic bracketing by using a setting on the camera to take several bracketed shots (in contrast to the photographer altering the settings by hand between each shot). Given the time it takes to accomplish multiple shots, it is typically, but not always, used for static subjects.

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Without further qualifications, the term bracketing usually refers to exposure bracketing: the photographer chooses to take one picture at a given exposure, one or more brighter, and one or more darker, in order to select the most satisfactory image. Technically, this can be accomplished by changing either the shutter speed or the aperture, or, with digital cameras, the ISO speed, or combinations thereof. Exposure can also be changed by altering the light level, for example using neutral-gray filters or changing the degree of illumination of the subject (e.g. artificial light, flash). Since the aim here is to alter the amount of exposure, but not otherwise the visual effect, exposure compensation for static subjects is typically performed by altering the shutter speed, for as long as this is feasible.

Many professional and advanced amateur cameras, including digital cameras, can automatically shoot a bracketed series of pictures, while even the cheaper ones have a less convenient but still effective manual exposure compensation control.

Exposure bracketing is indicated when dealing with high-contrast subjects and/or media with limited dynamic range, such as transparency film or CCD sensors in many digital cameras.

Exposure bracketing is also used to create fade-in or fade-out effects, for example in conjunction with multi-vision slide shows, or in combination with multiple exposure or flash.

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