Exposure bracketing is one of the most useful techniques in photography. In simple words, it means taking multiple photos of the same subject with different exposure settings. Therefore, bracketing is about changing your exposure: one photo at the camera meter’s recommendation, one under-exposed, and one over-exposed. Then the three photos could be merged into one photo using editing software to produce a High Dynamic Range (HDR) photo.
This article explains everything you need to know about bracketing, what is it, its types, and how to use it in order to take take the best possible photos.
Finally, we will present an example to show you how to use the famous software “Photoshop” to merge three bracketed photos to produce an HDR photo.
What is bracketing?
Professional photographers use the bracketing technique to ensure that they set their cameras correctly to catch the proper exposure in their photos, especially in challenging lighting situations.
Exposure bracketing means that you take two more pictures of the same scene: one slightly under-exposed (usually by dialing in negative exposure compensation, say -1/3EV), and the second one slightly over-exposed (usually by dialing in positive exposure compensation, say +1/3EV), So you will end up having three photos with different exposure settings: the one that you think it has the proper exposure, the second that is underexposed, and the third that is overexposed.
What is the dynamic range?
Simply, the dynamic range is the difference between the lightest and darkest tones in a scene, from pure white to pure black. In addition, a camera’s dynamic range refers to how many increments the image sensor can detect between pure black and white, and the tones in between.
The human eye can see almost 20 stops in perfect lighting conditions, while high-quality digital cameras can see only up to 15 stops of dynamic range. This means that our capability of seeing is superior to that of any advanced camera. In other words, our eyes can make out the level of details in the shadows and the highlights better than our cameras can.
So, when you spot an amazing scene with high dynamic range, and you want to catch it with your camera you have to remember the camera limitations and try to overcome them. Here comes the importance of using the bracketing technique.
What is HDR photography?
The term HDR stands for “high dynamic range.” For those who aren’t familiar with this technique. As we discuss the meaning of dynamic range in the previous paragraph, we know that if your scenes exceed the camera’s dynamic range, the highlights tend to wash out to white, and the shadows simply become black and you lose all the details. It is obviously difficult to take a photo that captures both ends of this spectrum (both highlights and shadows).
However, with some shooting techniques and advanced post-processing software, photographers have concluded ways to make it happen. This is basically what HDR is: a specific style of photo with an unusually high dynamic range that couldn’t otherwise be achieved in a single photograph.
Check the following video for more HDR sample photos
Why do we use exposure bracketing?
The reason we use the exposure technique is to overcome the situation when we are shooting at a high dynamic level of light in the scenes. We do this is because the camera might have been ‘deceived’ by the light (too much or too little) available and your main subject may be over or under-exposed. By taking these three shots, you are making sure that if this were ever the case, then you would have properly compensated for it.
As an example, you are taking a scene where there is a lot of light around your main subject (such as at the beach on a sunny day, or surrounded by bright snow). In this case, using Weighted-Average metering, your camera might be misjudged by the high light and exposed for it by closing down the aperture and/or using a faster shutter speed, with that setting, the main subject might be under-exposed. By taking an extra shot at a slight over-exposure, you would in fact be over-exposing the surroundings, but properly exposing the main subject.
