Bracketing is when you take the same photo multiple times, making only slight changes in the camera settings for each photograph. There are several types of bracketing: Exposure Bracketing, Focus Bracketing, Depth of Field Bracketing, Flash Bracketing and White Balance Bracketing. You change different camera settings for the different types of bracketing. In this post, we’re going to look at Exposure Bracketing.
A photographer will bracket exposures to ensure getting the best exposure. To bracket exposures, determine your best exposure and take that photograph. Then, take two more photos – one slightly underexposed and one slightly overexposed. By taking three slightly different exposures, the likelihood of getting the perfect exposure is increased.
Bracket as much or as little as needed. You can bracket in 1/3 stops if you know that you’re close to the right exposure and are trying to tweak it slightly. If you’re dealing with a contrasty scene then you may want to make more dramatic exposure changes – in 1/2 stops or full stops.
When shooting large format positive film, I make 1/3 stop adjustments because positive film has very little latitude.
Digital latitude is like shooting a negative – you don’t have to be as precise. You can bracket by 1/3, 1/2 or 1-stop and still be able to make a good print.
Personally, if I’m bracketing digitally, then I still bracket in 1/3 stops. If I’m dealing with a contrasty scene, then I’ll keep bracketing in 1/3 stops until I get 2 – stops underexposed and 2 – stops overexposed. Overkill? Perhaps. It takes me a little longer to edit out the bad exposures in post production. For me, it’s worth it to ensure that I’ve nailed the exposure. As you practice, you’ll find a method that works best for you.
Exposure Bracket in a Tricky Lighting Situation
Exposure Bracketing is especially helpful in tricky lighting situations. In this example, the sky is about 1 and 1/2 stops brighter than the mountains. With tricky lighting, it’s often more helpful to bracket in 1/2 or full stops. Below, is an example of 1/3 bracketing. Click the image to see how I bracketed 1 full stop underexposure and 1 full stop overexposure.
Highlights: Look at the differences in the sky from the underexposed photograph to the overexposed photograph. The underexposed photo captured more detail in the clouds, where the clouds are blown out in the overexposed shot.
Shadows: Look at the darkest part of the photo – the valley in the middle, under the hanging gardens. It’s too dark in the underexposed picture, but the overexposure captured additional detail in the shadow areas.
In the example above, I bracketed my exposure by changing the shutter speed.
Why change the Shutter Speed?
As we know from reading the exposure basics series, there are several settings we can change to affect exposure: Shutter Speed, Aperture, ISO or a combination of those. I typically consider changing my shutter speed first because it won’t affect my depth of field. There are times when changing the shutter speed won’t work for my photograph; in those cases, I’ll change my f-stop, instead. I leave changing my ISO as a last resort because I typically shoot with the lowest ISO possible.
Auto Exposure Bracketing – AEB
Many dSLR’s (and some advance point and shoots) have a setting called Auto Exposure Bracketing (AEB) that will do all the work for you. When using AEB, the camera takes each of the different exposures in quick succession, or even with a single click of the shutter button. The specifics vary between camera models, so read your manual to learn about Auto Exposure Bracketing on your camera. Here’s a quick overview of some common features:
1. Continuous Shooting – using AEB in burst / continuous shooting mode will take all exposures in quick succession when you hold the shutter button down once
2. Shutter Priority – Using AEB in shutter priority mode changes your f-stop between exposures.
3. Aperture Priority – Using AEB in aperture priority mode changes your shutter speed between exposures.
4. Stop difference – Many camera’s allow you to set how many stops difference you want between each photo.
5. Number of photos – Some camera’s take up 7 different exposures.