Exposure Bracketing: What It Is and How to Do It

Exposure Bracketing: What It Is and How to Do It

How many times have you snapped a beautiful scene, only to be disappointed when your images don’t adequately represent the reality? Though the camera’s images sometimes fall short, have no fear, because bracketing is here.

The Human Eye Versus Camera Sensor

Despite the obvious differences in vision and photography, our eyes and cameras work in a similar fashion, at least on a basic level. They both utilize a front lens for focusing and rely on a variable opening (aperture or pupil) to let in the right amount of light.

Imaging technology has come a long way, but the human brain still has far more processing power and can detect a larger range of light in a scene than any modern camera can in a single exposure. This is true, however, only in the comparison of human vision to individual snapshots. Over the time of a long exposure or combining frames,  a camera has a crucial advantage over the human eyesight .

Regardless of the light-gathering capability of a given long exposure, you’ll still sometimes find that your images are dull and lackluster compared to your eyes’ perception of the scene. When photographing on a sunny day, for instance, shadows and bright blowouts are commonplace and frustrating.

"But I shoot raw," you might say, pointing to your spiffy new t-shirt that boldly proclaims your camera settings to the unwashed masses of the photo-newbies. Maybe you feel you’re making maximum use of your camera's sensor, so brag a little (there’s nowhere else to go).

It's true, raw files are essential to capturing dynamic range in a scene. But I promise this: at some point, you will be in a situation in which bracketing is necessary, and a single raw file isn't going to cut it. We'll delve into those exact situations later, but first, let's talk about what bracketing is.

Defining Bracketing

By definition, bracketing is photographing a series of the same image, tweaking a single setting as you shoot. This results in a range of images that can serve various practical purposes.

a screenshot in Adobe Bridge of bracketed exposures

A series of bracketed exposures.

Typically, the term "bracketing" refers to changing exposure during multiple image captures. In other words, bracketing is gathering frames at various light steps. This can be done to choose the best exposure or later combine the photos for one image with more dynamic range. The end result of the latter creates work more attractive and true to human vision.

You can bracket for any setting. If you take a series of images at different focus points, that's focus bracketing. You can bracket ISO settings or even white balance in order to find the best result. Exposure bracketing is typically done with shutter speed. Keep in mind that if shutter speed is changing and your subject is moving, any motion within the frame can cause problems in compositing later.

If you're in a low light situation without a tripod, you will want to ensure that the slowest shutter speed in your bracketing range doesn't dip below handheld territory. This helps you avoid blurry images you didn't notice while you were snapping away.

Why Should You Exposure Bracket?

If you only shoot single exposures and don’t have to worry about full tonal range, bracketing might not apply to you. For practically everyone else who has not used this technique, bracketing expertise is handy in many situations.

My entry level photography began as most everyone else’s does: taking snapshots. Since journalism relies on the snapshot, this basic shooting technique has arguably produced the bulk of the world's most important photography, at least historically.

Of course, I started out taking single exposures. Then, moving into different genres, I became familiar with bracketing through the popular processing method known as HDR. We'll discuss HDR later.

an exterior photo of the front of an office building

The result of bracketed images after being composited: a natural-looking photo.

Manual Bracketing Versus Auto Bracketing

Automatic Exposure Bracketing

Most modern cameras come with an option to auto bracket.  Once auto bracketing is selected, decide how many frames you'd like to capture and set the range between each of those stops accordingly. For instance, if you'd like a series of five images all taken with just a single stop of light between them, your camera display should look like this:

camera display showing autobracket settings

Nikon's display for auto bracketing, showing five frames with one stop in between each.

Auto bracketing is great for handheld shooting. After choosing your auto bracket settings, set your shooting mode to burst and capture everything you need with one prolonged depression of the shutter. This way, your images will be easier to align, since little movement is created during burst shooting. You can also use a tripod.

Manual Exposure Bracketing

Manual exposure bracketing involves pushing your camera dial between each exposure. This is best achieved on tripod, though you can also do it handheld. The downside to handholding while manually bracketing is that your frame might jump around each time you move the camera dial and depress the shutter. This can produce problems when aligning images later on.

One advantage to manual bracketing is that you can push the camera as far one way or another as desired to gather dark or bright data, instead of relying on a set range of exposures to capture what you need (as in auto bracketing).

After you've taken your series of bracketed photos, you will merge them in post-processing. You have two options available: HDR and compositing. Let's take a look at both options, and I'll note why I prefer compositing over HDR for most situations.

HDR 

This processing technique stands for "high dynamic range," because it creates images with a more complex tonal range than a single exposure. HDR can be done in various ways: in Lightroom (available in more recent versions) or Photoshop, as well as via third-party software. You'll find that most of the software comes at a reasonable cost.

HDR Pros

  • Fast processing, good for artistic or bulk work. More common option for hobbyists because it's simpler, but many pros love it as well.
  • Utilizes tone mapping, which allows you to control the range of highlights and shadows.

HDR Cons

  • There's a learning curve involved. When done incorrectly, images can look garish and harsh (which might only be a positive if you're doing surreal fine art).
  • Default presets are usually subpar, and usually better when you set them yourself.
  • Less respected by professionals than compositing, as the output is often lower quality.

Compositing Exposures

Compositing Pros

  • Best result for quality. Technique more commonly used by pros.
  • More realistic output of images.
  • More control over ghosting (aberration created by movement) and range of tones.
  • Less noise in final output than HDR.

Compositing Cons

  • Learning curve: requires at least a basic understanding of layers and layer masks.
  • Time-consuming.

I prefer compositing, but many talented photographers do rely on HDR. Landscape photographers in particular often benefit from HDR, and others find it useful in the right context.

Still, HDR is often overused or inappropriately applied, producing a harsh, "overcooked" image that looks like a movie scene one would need a hazmat suit to enter safely.

an HDR phot of a stop sign in an alley

I took this image a decade ago when I was starting to learn about HDR. This is an extreme example of HDR poorly done; my digital photo teacher at the time commented during the critique: "If this is an attempt at HDR, something went horribly wrong."

What sort of applications do you use bracketing in? Next week, I'll delve into the various genres that use (and don't use) this technique, so please chime in with your ideas below.

Lead image by Jeshoots via Pexels.

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18 Comments

I've read that bracketing isn't suitable for shooting in Raw. Is this true and if so why? Thanks.

Wolfgang Mayerwieser's picture

Not true. Unless you have a very slow computer.

Scott Mason's picture

I should add that if your memory card has an extremely slow write speed, this would cause issues since you'd have a lag/freeze up after a burst of raw bracketed shots. If that's the case I recommend investing in new memory cards

Ariel Martini's picture

Bracketing: Something Canon users have to learn to compensate the lack of dynamic range

Michael Jin's picture

Shots fired, indeed... :O

Rob Mitchell's picture

Always in a doubtful situation, very rarely with the built in bracketing function because I leave it switched on too often. Duh.
More often then not I won't blend with a general HDR merge, more often with 2 or 3 processed RAW files in PS and use masks to work areas.

Scott Mason's picture

That's a good rule of thumb, Rob.

I've also have blended HDR with bracketed exposures with great results. It makes post processing even more time-consuming but once in a while it's worth it to go all out.

Vincent Alongi's picture

I'm not a huge landscape photographer but will fiddle with it more next spring. I'm doing occasional real estate photography work, and see the value in bracketing there for interior shots. As a portrait photog, it's obviously not a thing. But... a skill I'd like to work on regardless for other types of work.

Scott Mason's picture

Good luck Vincent, I think you'll be pleasantly surprised with your results!

Michael Jin's picture

Highlights -100
Shadows +100

Will curb the vast majority of dynamic range issues these days, although I'm personally of the opinion to just let unimportant bits go black or blow out to white. Call me lazy, but I'm just not about sitting at a computer and spending all that much time processing images like that.

Maybe if I did some serious landscape photography or something I would be more into it, but even then, the problem with multiple exposures is that things in a landscape move, so unless you want to spend a boatload of time on really perfecting the blend, you're probably going to end up with some artifacts whether it's blades of grass or leaves that move ever so slightly because of a breeze.

Scott Mason's picture

Michael, you said it yourself: Highlights -100 and Shadows + 100 is lazy and IMO it's not even a good practice.

Taking this approach with every photo will either give you the overcooked HDR look or a flat-looking image most of the time, since pushing the exposure like this leaves no contrast between shadows and highlights. The extreme processing push often turns out looking unnatural.

I agree that compositing is time consuming, but for many commercial photographers it's worth spending the time on each image. If we're charging our clients top dollar, you bet we're spending time to make each image look perfect.

I understand however that hobby shooting is a different story. If you like to take 1K + photos per vacation, it would be unreasonable to composite every scene and therefore it would be unfair to call someone lazy for bulk processing - it becomes a necessity.

Thanks for commenting!

Michael Jin's picture

It's absolutely lazy. 😁

"Highlights -100
Shadows +100

Will curb the vast majority of dynamic range issues these days"

This is the perfect example of how people misunderstand bracketing and dynamic range. The goal of bracketing is to expand the dynamic range of a single image; pushing sliders to 100 +/- anything is simply working within the confines of that single image. Not even close to being the same thing.

"although I'm personally of the opinion to just let unimportant bits go black or blow out to white."

First, this is bad practice if you plan to print anything. Second, it's not always about the absolute brightest or darkest part of the image, but how gradients transition around those parts. When you push the highlights down to -100 on a blue hour or nighttime cityscape, you'll find that bright lights that were blown out in the exposure aren't "recovered", they're pushed to a muddy white that's incapable of retaining any color because the detail is gone. And the more you blow out the core of the light sources, the uglier the transition around that core gets. And that's just one example. Shooting straight into the sun is another; try pushing the highlights down to -100 to recover the sky and the area around the sun looks awful. Again, it's the transition area that suffers the most.

I'm not saying bracketing should be used all the time; in fact, there are a lot of cases where people use it incorrectly because they don't understand the dynamic range of their cameras. But when it's needed, there isn't really a substitute for it. And it's certainly not "Highlights -100, Shadows +100".

Michael Jin's picture

<sigh>
Merry Christmas to you, too.

if you never wanna wanna lose a shot: use Bracketing..

Seems I've stirred up something of a hornets nest!!! Happy New year.

Highlights -100
Shadows +100 😂