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Photography Basics: All about Automatic Exposure Bracketing (AEB)

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The experience and result of photography are often disturbed by factors such as tricky lighting or a high variation between the dark and bright areas wherein one is not sure of the exposure setting to choose. While manual experimentation with exposure control followed by series of shots is a workaround, it may take time and cause moment loss in case of photography in a variable environment. The Automatic Exposure Bracketing (AEB) feature, thus, comes to rescue. It is a feature of most modern DSLR cameras that aids quick 3 shots without the need of change in manual settings between frames.

While beginners in photography may find the concept of automatic exposure bracketing a confusing one and thus avoid it or stay uninformed of its use.

But, it isn’t as complicated as it seems!

Automatic exposure bracketing is a setting of the camera that is used to capture the same scene with varying exposure values. The number of captures is 3 or more. The end result is a correctly exposed picture along with 2 others that are overexposed and underexposed respectively.

Automatic Exposure Bracketing: Example and Uses

Automatic exposure bracketing (AEB) is required because the automatic mode in the camera isn’t the most accurate. Certain lighting situations cannot be handled perfectly by the camera.

For instance, snow, the brightness, and whiteness of snow gives the illusion of excessive light to the camera and hence causes underexposure for the camera wants to handle the excessive light. The result is an image that shows grayish snow that isn’t mostly liked by photographers.

Automatic Exposure Bracketing
Image showing underexposed snow ( Source )

AEB, thus, enables clicking pictures at an exposure value higher and lower than the automatically chosen value. Exposure value can be considered as simply a scale of darkness or brightness relative to the current setting.

Automatic exposure bracketing is a setting that is quite useful, especially for those who capture nature and landscapes. If one is shooting a landscape using creative modes of the camera such as shutter and aperture priority, AEB feature will help to take 3 shots with different exposures and hence help achieve the expected exposure.

Another application of AEB is in HDR photography as the basic concept of creation of an HDR image is the combination of images with different exposure values and hence, ensuring even exposure across the frame. The setting is found on almost all digital cameras shown by different symbols. The value of underexposure and overexposure is generally the same.

Reasons for using Automatic Exposure Bracketing in Photography

Getting Shots with Proper Exposure

Exposure bracketing was put to extensive use during the days when cameras were analog and instant feedback wasn’t available in the form of histograms or camera screen. Then photographers would take multiple shots with varying exposure values. But AEB solves that trouble in the digital era.

Automatic Exposure Bracketing: Capturing the Perfect Picture

HDR Photography

As discussed above, AEB forms the basis of HDR photography. The dynamic range of camera sensor may not be wide enough to cover the dynamic range of the scene and thus HDR images are created by merging multiple shots with varying exposure values.

Automatic Exposure Bracketing: Capturing the Perfect Picture

The Blending of Exposure

Merging multiple shots and also managing more control over the process of blending is offered by the technique called exposure blending which is more complex as compared to HDR. Photographers take up manual blending in photoshop using luminosity masks in this advanced technique.

Automatic Exposure Bracketing: Capturing the Perfect Picture

Initial Learning

Amateur photographers can learn a great deal about exposure using automatic exposure bracketing. A good way to approach it would be to analyze images after each shoot to find out situations when the automatic camera setting made a wrong judgment. This would enable handling similar situations in future.

Digital Dodging and Burning

The decision of deleting the extra shots right away needs to be made, but the deletion must be postponed until you get the opportunity to upload the images to a PC and access them using an image editing application. The layers’ functionality of editing software such as Photoshop, enables loading all the shots in different layers and then erasing the over and under exposed parts in individual layers to achieve a final shot with the properly exposed subject and surroundings.

Using this feature one can shoot even in situations with extreme lighting wherein multiple shots with auto exposure bracketing can be combined to achieve the perfect picture. If done properly, this tedious task can generate awesome results. It is the digital equivalent of film dodging and burning that is done in the case of darkroom film development.

Get to know about F-stop in DSLR photography, here!

Steps to Take before starting Automatic Exposure Bracketing

1. Setting up on a tripod

Eliminating movement during exposure is extremely important to achieve results from automatic exposure bracketing to rule out issues of misalignment to enable image burning into an HDR image.

2. Predetermine the intended camera mode

3. Autofocus must be disabled

Enabled autofocus may cause a resultant shift in focus during AEB shots, thus self-composure of shot and focus is a must.

4. Enable shutter delay

AEB requires enabling the 10 or 2-second shutter delay.

5. Turn on AEB setting on camera

How to use Automatic Exposure Bracketing on your Camera

Different camera brands may have a different way of accessing the AEB feature but it is positive that it is available in mostly all modern cameras. The principle is essentially the same but different steps are required for different cameras. The following are steps in some major cameras:

  1. Turn on the camera and open the screen.
  2. Access the menu using menu button.
  3. Access the tab with camera icon, choose expo.comp/AEB, press .
  4. Set AEB amount by turning the main dial.
  5. Exposure compensation amount can be set by pressing the multi-controller. Combining AEB with exposure compensation will apply AEB based on the amount of exposure compensation.
  6. Set using the set button.
  7. LCD panel will display the AEB level once the button is pressed to exit the menu.
  8. Completely press the shutter button after focusing.
  9. The bracketed shots will be in a sequence of standard, decreased and increased.

Turning on Automatic Exposure Bracketing

The symbol of AEB is as below, it can be found on the button panel (labeled as AEB or BLK) in some cameras and needs to be accessed from the menu in others.

Automatic Exposure Bracketing
AEB symbol ( Source )

The user manual gives a better idea of the specifics but generally, it is quite easy to set up. If you need to access it using the menu it looks something like below-

Automatic Exposure Bracketing

Adjusting Automatic Exposure Bracketing Settings

Turning on AEB must be followed by adjusting the settings according to preferences.

Depending on the camera, one may or may not be able to choose the number of bracketed shots to take ranging usually from 3-9.

Automatic Exposure Bracketing: Capturing the Perfect Picture

Amount of under and over exposure must also be set ranging from 1/3 to 2 stops

Drive Mode and its Activation

One is enabled to capture a series of bracketed images once AEB is activated and settings are adjusted. It requires pressing the shutter button for every shot.

Automatic Exposure Bracketing: Capturing the Perfect Picture

The easier and quicker way to achieve this is the drive mode in your camera also referred to as continuous shooting or burst mode. Holding the shutter button down enables shooting all the bracketed shots in one burst.

While it is usually done via the dial on the body of the camera, the user manual may guide better in the case of doubt.

Working of Automatic Exposure Bracketing in Different Modes

AEB works differently depending on the mode of shooting. The following are different modes and how AEB works in them:

  1. Program mode: Bracketing is done by varying the shutter speed to change exposure
  2. Aperture priority mode: Shutter speed is changed for AEB
  3. Shutter priority mode: Change in aperture causes bracketing to create underexposed and overexposed images

AEB has limited use when working in shutter priority mode as the change in the aperture to create different scenarios for exposure also alters the depth of field for the image. Also, if the need of normal exposure requires fixed or specific aperture, shutter priority mode proves to be unfeasible.

Also, read: How to know your lenses sweet spot for sharper images!

AEB is a very useful tool in photography, don’t let it intimidate you. It can be used well in tricky light situations and help achieve HDR images. Perfectly exposed clicks can be achieved easily as per requirements if AEB is used well. Now that you know the importance and functionality of AEB, it’s time for you to flaunt your photography skills every time when you’re out there clicking pictures.