Exposure bracketing is a technique widely used in HDR images to make every pixel of the image correctly exposed to light, especially in challenging lighting situations. HDR or High Dynamic Range is is a simple yet highly effective technique, used by professional photographers to generate images having a greater dynamic range and more luminosity than the standard images. In exposure bracketing,
When we expose the camera for a scene, it will automatically select the aperture and shutter speed combination, which it believes will give a perfectly exposed picture.
In exposure bracketing, we take two more images. One image is a bit over-exposed, and the other one is a bit under-exposed. The reason for doing this is that sometimes it is possible that the camera is not focusing correctly on the main subject or the exposure meter gives incorrect suggestions. This might leave the main subject improperly exposed, that is, slightly over or underexposed. When we stack these three images, the output will give us an image that will be adequately exposed to light.
How to take bracketed exposures?
If you are clicking the picture of a room which has a window and outside the window, there is a garden which is also visible. Now, if you click a picture which is underexposed, the window will be overexposed, and the room will be properly exposed. And if you click an overexposed picture, the window will be adequately exposed, and the room will be overexposed. Again, if you click a picture using the automatic adjustments done by the exposure meter, the picture might not be perfectly exposed. So, we will stack these three images together using photo editing software, and the resulting image will be an image having properly exposed room as well as a properly exposed window.
Today, many digital cameras have an auto-exposure bracketing option. When you select this option, the camera will take three shots–one overexposed, one underexposed and one standard. These images will be then loaded in editing software, like photoshop, by the user and they can be stacked together as layers. The perfect shot can be obtained by erasing the underexposed and overexposed parts from each layer. The result will be a properly exposed image which would have been impossible to click otherwise.
You can also see in the featured image that the left part of the image is under-exposed, while the right is over-exposed and the one in the centre is the standard exposure shot.
Also read: Top 7 editing tips for Lightroom