Bracketing
Encyclopedia
In photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...

, 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 variation in 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...

 parameters has a comparatively large effect on the resulting image. Autobracketing
Autobracketing
Autobracketing is a feature of some more advanced cameras, whether film or digital cameras, particularly single-lens reflex cameras, where the camera will take several successive shots with slightly different settings. Later, the best-looking pictures can be picked from the batch...

 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.

Exposure bracketing

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 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, can automatically shoot a bracketed series of pictures, while even the cheaper ones have a less convenient but still effective manual 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...

 control.

Exposure bracketing is indicated when dealing with high-contrast subjects and/or media with limited dynamic range
Dynamic range
Dynamic range, abbreviated DR or DNR, is the ratio between the largest and smallest possible values of a changeable quantity, such as in sound and light. It is measured as a ratio, or as a base-10 or base-2 logarithmic value.-Dynamic range and human perception:The human senses of sight and...

, such as transparency
Transparency (photography)
In photography, a reversal film is a type of photographic film that produces a positive image on a transparent base. Also known as dias or slide. The film is processed to produce transparencies or diapositives instead of negatives and prints...

 film or CCD
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...

 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
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:...

 or flash.

When shooting using negative film, the person printing the pictures to paper must not compensate for the deliberately underexposed and overexposed pictures. If a set of photos are bracketed but are then printed using automated equipment, the equipment may assume that the camera or photographer made an error and automatically "correct" the shots it determines are "improperly" done.

Images produced using exposure bracketing are often combined in postprocessing to create a high dynamic range image
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...

 that exposes different portions of the image by different amounts.

Flash bracketing

Flash bracketing is a technique of working with electronic flash, especially when used as fill flash
Fill flash
Fill flash is a photographic technique used to brighten deep shadow areas, typically outdoors on sunny days, though the technique is useful any time the background is significantly brighter than the subject of the photograph, particularly in backlit subjects...

 in combination with existing light, maintaining the overall amount of exposure. The amount of light provided by the flash is varied in a bracketed series in order to find the most pleasing combination of ambient light and fill flash. If used for this purpose, flash bracketing can be differentiated from normal exposure bracketing via flash, although the usage of the term is not strict.

Alternatively, if the amount of flash light cannot be altered easily (for example with studio flashes), it is also possible to alter the aperture instead, however, this will also affect 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...

 and ambient light exposure. If the flash to ambient light ratio is to be changed in flash bracketing using this technique, it is necessary to counter-shift the shutter speed as well in order to maintain the level of ambient light exposure, however, with focal plane shutters, this is often difficult to achieve given their limited X-sync speed - and flash techniques such as high-speed synchronization are not available with studio flashes.

Depth-of-field bracketing

DOF (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...

) bracketing comprises taking a series of pictures in stepped apertures (f-stops
F-Stops
F-Stops is an album by American jazz trombonist and composer Craig Harris recorded in 1993 and released on the Italian Soul Note label.-Reception:...

), while maintaining the exposure, either by counter-shifting 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....

 or, with digital cameras, adapting the ISO speed accordingly. In the first case, it will also change the amount of motion blur in the picture. In the second case, it may visibly affect image noise and contrast.

Combining DOF bracketing with multiple 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:...

, the so called STF effect (for Smooth Trans Focus) can be achieved as implemented in the Minolta Maxxum 7's automated STF function. This closely resembles 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 optical effect of the 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 in the Minolta/Sony STF 135 mm f/2.8 [T4.5]'s special-purpose lens.

Focus bracketing

Focus bracketing is useful in situations with limited 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...

, such as macro photography
Macro photography
Macrophotography is close-up photography, usually of very small subjects. Classically a macrophotograph is one in which the size of the subject on the negative is greater than life size. However in modern use it refers to a finished photograph of a subject at greater than life size...

, where one may want to make a series of exposures with different positions of the focal plane
Cardinal point (optics)
In Gaussian optics, the cardinal points consist of three pairs of points located on the optical axis of an ideal, rotationally symmetric, focal, optical system...

 and then choose the one in which the largest portion of the subject is in focus, or combine the in-focus portions of multiple exposures digitally (focus stacking
Focus stacking
Focus stacking is a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field than any of the individual source images...

). Usually this involves the use of software with unsharp masking
Unsharp masking
Unsharp masking is an image manipulation technique, often available in digital image processing software.The "unsharp" of the name derives from the fact that the technique uses a blurred, or "unsharp," positive to create a "mask" of the original image...

, a filtering algorithm that removes out-of-focus portions of each exposure. The in-focus portions are then "stacked"; combined into a single image. Focus stacking is challenging, in that the subject (as in all brackets) must stay still and that as the focal point changes, the magnification (and position) of the images change. This must then be corrected in a suitable application by transforming the image.

White balance bracketing

White balance bracketing, which is specific to digital photography
Digital photography
Digital photography is a form of photography that uses an array of light sensitive sensors to capture the image focused by the lens, as opposed to an exposure on light sensitive film...

, provides a way of dealing with mixed lighting by shooting several images with different white point settings, often ranging from bluish images to reddish images.

When 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), white balance can be arbitrarily changed in postprocessing as well, so white balance bracketing is particularly useful for reviewing different white balance settings in the field.

In contrast to manual white balance bracketing, which requires the photographer to take multiple shots, automatic white-balance bracketing, as it is implemented in many digital cameras, requires a single exposure only.

ISO bracketing

See Also

  • Autobracketing
    Autobracketing
    Autobracketing is a feature of some more advanced cameras, whether film or digital cameras, particularly single-lens reflex cameras, where the camera will take several successive shots with slightly different settings. Later, the best-looking pictures can be picked from the batch...


In photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...

, 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 variation in 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...

 parameters has a comparatively large effect on the resulting image. Autobracketing
Autobracketing
Autobracketing is a feature of some more advanced cameras, whether film or digital cameras, particularly single-lens reflex cameras, where the camera will take several successive shots with slightly different settings. Later, the best-looking pictures can be picked from the batch...

 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.

Exposure bracketing


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 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, can automatically shoot a bracketed series of pictures, while even the cheaper ones have a less convenient but still effective manual 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...

 control.

Exposure bracketing is indicated when dealing with high-contrast subjects and/or media with limited dynamic range
Dynamic range
Dynamic range, abbreviated DR or DNR, is the ratio between the largest and smallest possible values of a changeable quantity, such as in sound and light. It is measured as a ratio, or as a base-10 or base-2 logarithmic value.-Dynamic range and human perception:The human senses of sight and...

, such as transparency
Transparency (photography)
In photography, a reversal film is a type of photographic film that produces a positive image on a transparent base. Also known as dias or slide. The film is processed to produce transparencies or diapositives instead of negatives and prints...

 film or CCD
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...

 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
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:...

 or flash.

When shooting using negative film, the person printing the pictures to paper must not compensate for the deliberately underexposed and overexposed pictures. If a set of photos are bracketed but are then printed using automated equipment, the equipment may assume that the camera or photographer made an error and automatically "correct" the shots it determines are "improperly" done.

Images produced using exposure bracketing are often combined in postprocessing to create a high dynamic range image
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...

 that exposes different portions of the image by different amounts.

Flash bracketing


Flash bracketing is a technique of working with electronic flash, especially when used as fill flash
Fill flash
Fill flash is a photographic technique used to brighten deep shadow areas, typically outdoors on sunny days, though the technique is useful any time the background is significantly brighter than the subject of the photograph, particularly in backlit subjects...

 in combination with existing light, maintaining the overall amount of exposure. The amount of light provided by the flash is varied in a bracketed series in order to find the most pleasing combination of ambient light and fill flash. If used for this purpose, flash bracketing can be differentiated from normal exposure bracketing via flash, although the usage of the term is not strict.

Alternatively, if the amount of flash light cannot be altered easily (for example with studio flashes), it is also possible to alter the aperture instead, however, this will also affect 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...

 and ambient light exposure. If the flash to ambient light ratio is to be changed in flash bracketing using this technique, it is necessary to counter-shift the shutter speed as well in order to maintain the level of ambient light exposure, however, with focal plane shutters, this is often difficult to achieve given their limited X-sync speed - and flash techniques such as high-speed synchronization are not available with studio flashes.

Depth-of-field bracketing


DOF (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...

) bracketing comprises taking a series of pictures in stepped apertures (f-stops
F-Stops
F-Stops is an album by American jazz trombonist and composer Craig Harris recorded in 1993 and released on the Italian Soul Note label.-Reception:...

), while maintaining the exposure, either by counter-shifting 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....

 or, with digital cameras, adapting the ISO speed accordingly. In the first case, it will also change the amount of motion blur in the picture. In the second case, it may visibly affect image noise and contrast.

Combining DOF bracketing with multiple 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:...

, the so called STF effect (for Smooth Trans Focus) can be achieved as implemented in the Minolta Maxxum 7's automated STF function. This closely resembles 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 optical effect of the 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 in the Minolta/Sony STF 135 mm f/2.8 [T4.5]'s special-purpose lens.

Focus bracketing


Focus bracketing is useful in situations with limited 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...

, such as macro photography
Macro photography
Macrophotography is close-up photography, usually of very small subjects. Classically a macrophotograph is one in which the size of the subject on the negative is greater than life size. However in modern use it refers to a finished photograph of a subject at greater than life size...

, where one may want to make a series of exposures with different positions of the focal plane
Cardinal point (optics)
In Gaussian optics, the cardinal points consist of three pairs of points located on the optical axis of an ideal, rotationally symmetric, focal, optical system...

 and then choose the one in which the largest portion of the subject is in focus, or combine the in-focus portions of multiple exposures digitally (focus stacking
Focus stacking
Focus stacking is a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field than any of the individual source images...

). Usually this involves the use of software with unsharp masking
Unsharp masking
Unsharp masking is an image manipulation technique, often available in digital image processing software.The "unsharp" of the name derives from the fact that the technique uses a blurred, or "unsharp," positive to create a "mask" of the original image...

, a filtering algorithm that removes out-of-focus portions of each exposure. The in-focus portions are then "stacked"; combined into a single image. Focus stacking is challenging, in that the subject (as in all brackets) must stay still and that as the focal point changes, the magnification (and position) of the images change. This must then be corrected in a suitable application by transforming the image.

White balance bracketing


White balance bracketing, which is specific to digital photography
Digital photography
Digital photography is a form of photography that uses an array of light sensitive sensors to capture the image focused by the lens, as opposed to an exposure on light sensitive film...

, provides a way of dealing with mixed lighting by shooting several images with different white point settings, often ranging from bluish images to reddish images.

When 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), white balance can be arbitrarily changed in postprocessing as well, so white balance bracketing is particularly useful for reviewing different white balance settings in the field.

In contrast to manual white balance bracketing, which requires the photographer to take multiple shots, automatic white-balance bracketing, as it is implemented in many digital cameras, requires a single exposure only.

ISO bracketing




See Also

  • Autobracketing
    Autobracketing
    Autobracketing is a feature of some more advanced cameras, whether film or digital cameras, particularly single-lens reflex cameras, where the camera will take several successive shots with slightly different settings. Later, the best-looking pictures can be picked from the batch...


In photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...

, 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 variation in 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...

 parameters has a comparatively large effect on the resulting image. Autobracketing
Autobracketing
Autobracketing is a feature of some more advanced cameras, whether film or digital cameras, particularly single-lens reflex cameras, where the camera will take several successive shots with slightly different settings. Later, the best-looking pictures can be picked from the batch...

 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.

Exposure bracketing


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 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, can automatically shoot a bracketed series of pictures, while even the cheaper ones have a less convenient but still effective manual 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...

 control.

Exposure bracketing is indicated when dealing with high-contrast subjects and/or media with limited dynamic range
Dynamic range
Dynamic range, abbreviated DR or DNR, is the ratio between the largest and smallest possible values of a changeable quantity, such as in sound and light. It is measured as a ratio, or as a base-10 or base-2 logarithmic value.-Dynamic range and human perception:The human senses of sight and...

, such as transparency
Transparency (photography)
In photography, a reversal film is a type of photographic film that produces a positive image on a transparent base. Also known as dias or slide. The film is processed to produce transparencies or diapositives instead of negatives and prints...

 film or CCD
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...

 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
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:...

 or flash.

When shooting using negative film, the person printing the pictures to paper must not compensate for the deliberately underexposed and overexposed pictures. If a set of photos are bracketed but are then printed using automated equipment, the equipment may assume that the camera or photographer made an error and automatically "correct" the shots it determines are "improperly" done.

Images produced using exposure bracketing are often combined in postprocessing to create a high dynamic range image
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...

 that exposes different portions of the image by different amounts.

Flash bracketing


Flash bracketing is a technique of working with electronic flash, especially when used as fill flash
Fill flash
Fill flash is a photographic technique used to brighten deep shadow areas, typically outdoors on sunny days, though the technique is useful any time the background is significantly brighter than the subject of the photograph, particularly in backlit subjects...

 in combination with existing light, maintaining the overall amount of exposure. The amount of light provided by the flash is varied in a bracketed series in order to find the most pleasing combination of ambient light and fill flash. If used for this purpose, flash bracketing can be differentiated from normal exposure bracketing via flash, although the usage of the term is not strict.

Alternatively, if the amount of flash light cannot be altered easily (for example with studio flashes), it is also possible to alter the aperture instead, however, this will also affect 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...

 and ambient light exposure. If the flash to ambient light ratio is to be changed in flash bracketing using this technique, it is necessary to counter-shift the shutter speed as well in order to maintain the level of ambient light exposure, however, with focal plane shutters, this is often difficult to achieve given their limited X-sync speed - and flash techniques such as high-speed synchronization are not available with studio flashes.

Depth-of-field bracketing


DOF (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...

) bracketing comprises taking a series of pictures in stepped apertures (f-stops
F-Stops
F-Stops is an album by American jazz trombonist and composer Craig Harris recorded in 1993 and released on the Italian Soul Note label.-Reception:...

), while maintaining the exposure, either by counter-shifting 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....

 or, with digital cameras, adapting the ISO speed accordingly. In the first case, it will also change the amount of motion blur in the picture. In the second case, it may visibly affect image noise and contrast.

Combining DOF bracketing with multiple 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:...

, the so called STF effect (for Smooth Trans Focus) can be achieved as implemented in the Minolta Maxxum 7's automated STF function. This closely resembles 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 optical effect of the 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 in the Minolta/Sony STF 135 mm f/2.8 [T4.5]'s special-purpose lens.

Focus bracketing


Focus bracketing is useful in situations with limited 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...

, such as macro photography
Macro photography
Macrophotography is close-up photography, usually of very small subjects. Classically a macrophotograph is one in which the size of the subject on the negative is greater than life size. However in modern use it refers to a finished photograph of a subject at greater than life size...

, where one may want to make a series of exposures with different positions of the focal plane
Cardinal point (optics)
In Gaussian optics, the cardinal points consist of three pairs of points located on the optical axis of an ideal, rotationally symmetric, focal, optical system...

 and then choose the one in which the largest portion of the subject is in focus, or combine the in-focus portions of multiple exposures digitally (focus stacking
Focus stacking
Focus stacking is a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field than any of the individual source images...

). Usually this involves the use of software with unsharp masking
Unsharp masking
Unsharp masking is an image manipulation technique, often available in digital image processing software.The "unsharp" of the name derives from the fact that the technique uses a blurred, or "unsharp," positive to create a "mask" of the original image...

, a filtering algorithm that removes out-of-focus portions of each exposure. The in-focus portions are then "stacked"; combined into a single image. Focus stacking is challenging, in that the subject (as in all brackets) must stay still and that as the focal point changes, the magnification (and position) of the images change. This must then be corrected in a suitable application by transforming the image.

White balance bracketing


White balance bracketing, which is specific to digital photography
Digital photography
Digital photography is a form of photography that uses an array of light sensitive sensors to capture the image focused by the lens, as opposed to an exposure on light sensitive film...

, provides a way of dealing with mixed lighting by shooting several images with different white point settings, often ranging from bluish images to reddish images.

When 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), white balance can be arbitrarily changed in postprocessing as well, so white balance bracketing is particularly useful for reviewing different white balance settings in the field.

In contrast to manual white balance bracketing, which requires the photographer to take multiple shots, automatic white-balance bracketing, as it is implemented in many digital cameras, requires a single exposure only.

ISO bracketing



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