Autobracketing

Autobracketing is a feature of some more advanced camera

Camera

A camera is a device that records and stores images. These images may be still photographs or moving images such as videos or movies. The term camera comes from the camera obscura , an early mechanism for projecting images...

s, whether film

Photographic film

Photographic film is a sheet of plastic coated with an emulsion containing light-sensitive silver halide salts with variable crystal sizes that determine the sensitivity, contrast and resolution of the film...

 or digital camera

Digital camera

A digital camera is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. It is the main device used in the field of digital photography...

s, particularly single-lens reflex camera

Single-lens reflex camera

A single-lens reflex camera is a camera that typically uses a semi-automatic moving mirror system that permits the photographer to see exactly what will be captured by the film or digital imaging system, as opposed to pre-SLR cameras where the view through the viewfinder could be significantly...

s, where the camera will take several successive shots (often three) with slightly different settings. Later, the best-looking pictures can be picked from the batch. When the photographer achieves the same result by changing the camera settings between each shot, this is simply called bracketing

Bracketing

In photography, bracketing is the general technique of taking several shots of the same subject using different or the same 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...

.

Auto Exposure Bracketing

The most common type of autobracketing is exposure autobracketing (often abbreviated to AEB for Auto Exposure Bracketing or BR for Bracketing), where the camera is set to capture the same image several times with different exposure

Exposure (photography)

In photography, exposure is the total amount of light allowed to fall on the photographic medium during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value and scene luminance over a specified area.In photographic jargon, an exposure...

 settings, both over-exposed and under-exposed (lighter and darker) compared to the current setting on the camera, which may already include exposure compensation

Exposure compensation

Exposure compensation is a technique for adjusting the exposure indicated by a photographic exposure meter, in consideration of factors that may cause the indicated exposure to result in a less-than-optimal image. Factors considered may include unusual lighting distribution, variations within a...

. Depending on the camera, the difference between each of the autobracketed shots could be anywhere from one-quarter up to three full stops

Exposure value

In photography, exposure value denotes all combinations of a camera's shutter speed and relative aperture that give the same exposure. In an attempt to simplify choosing among combinations of equivalent camera settings, the concept was developed by the German shutter manufacturer in the 1950s...

 in each direction, in full, half, third or quarter stop increments, ranging from two up to nine shots in series. Sometimes it is possible to either define the order, in which the shots will be taken, or to give an offset as a start-point of the bracketing series. More sophisticated equipment allows auto-exposure bracketing to be combined with timer and intervalometer

Intervalometer

An intervalometer is a device which counts intervals of time. . Such devices commonly are used to signal, in accurate time intervals, the operation of some other device...

 functions as well.

Cameras can perform autobracketing by adjusting either the shutter speed

Shutter speed

In photography, shutter speed is a common term used to discuss exposure time, the effective length of time a camera's shutter is open....

 (typically in aperture priority

Aperture priority

Aperture priority, often abbreviated A or Av on a camera mode dial, is a setting on some cameras that allows the user to choose a specific aperture value while the camera selects a shutter speed to match. The camera will ensure proper exposure...

 mode, sometimes also in manual or program mode) or the aperture setting (typically in shutter priority

Shutter priority

Shutter priority refers to a setting on some cameras that allows the user to choose a specific shutter speed while the camera adjusts the aperture to ensure correct exposure...

 mode). In programmed exposure mode, many cameras will alter both parameters at the same time. Some cameras allow to swap the parameter used for shifting in manual mode. Digital cameras may also alter the ISO setting if auto-ISO is enabled.

Exposure autobracketing is most commonly used with color reversal film (slide film) because of its small exposure latitude compared with print film (which has a wide exposure latitude) and digital cameras (which enable the photographer to review the captured image).
In digital photography, autobracketing is convenient to shoot pictures for high dynamic range imaging

High dynamic range imaging

In image processing, computer graphics, and photography, high dynamic range imaging is a set of techniques that allows a greater dynamic range between the lightest and darkest areas of an image than current standard digital imaging techniques or photographic methods...

.

Auto Flash Bracketing

Automatic flash bracketing (sometimes abbreviated to FBR for Flash Bracketing or FEB for Flash Exposure Bracketing) is typically performed by altering the flash output of a connected dedicated flash accordingly. Using non-dedicated studio flashes, for example on the PC socket, flash bracketing can be carried out by altering the aperture, however, this will also affect ambient light and the depth of field

Depth of field

In optics, particularly as it relates to film and photography, depth of field is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image...

.

If, in manual mode, a camera defaults to alter the shutter speed, it might be necessary to swap the parameters used for shifting in order for the camera to alter the aperture instead.

Since the flash may need time to recharge between the shots, some cameras fall back to single-advance drive mode during auto flash bracketing, even if they are otherwise configured for continuous-advance drive.

Auto ISO Bracketing

Auto White-Balance Bracketing

Another common form of autobracketing is white balance autobracketing (sometimes abbreviated to WBB for White Balance Bracketing); this applies only to digital cameras, not to film cameras.

This function provides a way of dealing with mixed lighting by having the camera take one shot and process the raw sensor data several times for slightly different white point settings, with both higher and lower color temperature

Color temperature

Color temperature is a characteristic of visible light that has important applications in lighting, photography, videography, publishing, manufacturing, astrophysics, and other fields. The color temperature of a light source is the temperature of an ideal black-body radiator that radiates light of...

s (bluer and redder) compared to the current setting on the camera. Typically, the amount of offset can be configured.

Since shooting in a camera's RAW

RAW image format

A camera raw image file contains minimally processed data from the image sensor of either a digital camera, image scanner, or motion picture film scanner. Raw files are so named because they are not yet processed and therefore are not ready to be printed or edited with a bitmap graphics editor...

 format (if supported) the white balance can be arbitrarily changed in postprocessing as well at a later stage, white balance bracketing is particularly useful for reviewing different white balance settings in the field.

Auto Focus Bracketing

Smooth Trans Focus function

A combination of depth-of-field bracketing with multi exposure

Multiple exposure

In photography, a multiple exposure is the superimposition of two or more individual exposures to create a single photograph. The exposure values may or may not be identical to each other.-Overview:...

 can be used to emulate the Bokeh

Bokeh

In photography, bokeh is the blur, or the aesthetic quality of the blur, in out-of-focus areas of an image, or "the way the lens renders out-of-focus points of light."...

-pleasing effect of the Minolta/Sony Smooth Trans Focus 135mm f/2.8 [T4.5] special purpose lens, which accomplishes this by utilizing a concave neutral-gray tinted lens element in the optical path as an apodization

Apodization

Apodization literally means "removing the foot". It is the technical term for changing the shape of a mathematical function, an electrical signal, an optical transmission or a mechanical structure.- Apodization in signal processing :...

 filter. This is implemented in the Minolta Maxxum 7's STF function in form of an automatically calculated and pre-compensated

Exposure compensation

Exposure compensation is a technique for adjusting the exposure indicated by a photographic exposure meter, in consideration of factors that may cause the indicated exposure to result in a less-than-optimal image. Factors considered may include unusual lighting distribution, variations within a...

seven-fold multi-exposure with DOF bracketing.