There are many different ways of shooting HDR photos, but today we’re going to look at HDR photography using Exposure Bracketing. This is a bit more work than using your camera’s built-in HDR mode but offers a number of advantages such as the ability to shoot in RAW format, and more control over the end result.
What is HDR Photography?
HDR photography is a technique used to overcome the inability of today’s cameras to adequately capture the full dynamic range of settings that include both very bright and very dark regions.
A classic example is when shooting an interior room with windows on a sunny day. If you tell the camera to expose the room properly, the windows will be completely white with light and you won’t see any of the detail from outdoors. On the other hand, if you set the exposure for the windows, then the entire room will be exposed deep in shadow, lacking most of the detail that you desire.
HDR stands for High Dynamic Range because it allows you to increase the range of contrast in your image — more detail in the shadows and highlights, to produce a photo that looks much more evenly lit.
There are several different methods of producing HDR photos. Most new DSLR cameras have a built-in HDR mode where it will record multiple exposures of an image and automatically merge them to produce a final HDR image. The problem with this approach is that in most cameras only a JPG image is supported as output (as opposed to RAW), and because the whole process is automatic, the photographer doesn’t have much control over the end result.
Today I’m going to show you a much better approach for HDR photography using exposure bracketing, which is slightly more effort upfront, but allows much more control and produces a better looking HDR photo.
How to use Exposure Bracketing for HDR Photography
We are going to use a feature built-in to most DSLR cameras now called Auto Exposure Bracketing. By turning on this mode, when you press the shutter release button, the camera will actually take several photos at a range of different exposures.
By setting the parameters appropriately, we can ensure that at least one shot is exposed for the bright areas in our scene, and at least one is exposed for the shadows. We can then combine these exposures into a single image using a computer.
The step-by-step instructions I am going to provide below on how to use exposure bracketing are geared towards Nikon cameras because that is what I use. The process should be very similar for users of Canon or other camera makes.
Step 1: Enable RAW photo format
While not absolutely essential to do so, it’s highly recommended to use RAW format for HDR photography. RAW images store 14 bits of image information, as opposed to 8 bits for JPG. Since we are trying to maximize the amount of color information available to produce our final HDR image, it makes sense to use the RAW format.
Step 2: Choose Auto-Exposure Bracketing in Camera Settings
Nikon cameras allow bracketing for several different camera settings, not only exposure. Since it’s exposure we want to bracket for in HDR photography, we need to tell the camera to do so. Following are the steps on a Nikon D750 camera:
i) Go to the (e) Bracketing/flash submenu in the Custom Setting Menu
ii) Select e6) Auto bracketing set
iii) Choose AE only mode. This will tell the camera to bracket the exposure only.
Step 3: Choose the number of shots
We need to tell the camera how many shots to take. One shot will always be at the camera’s metered exposure with no adjustment. The number of shots we specify will be evenly spaced above and below this reference point.
For my HDR photos, I usually keep it simple and choose 3 shots to start with. This means that there will be one shot at the reference exposure, one underexposed, and one overexposed.
i) Press and hold down the BKT button
ii) Rotate the command dial until you see the desired number of shots displayed on the LCD screen. Choose 3F if you want three shots as I have recommended.
Step 4: Choose the Exposure Increment
We need to also tell the camera exactly how much we want it to underexpose and overexpose each step. I like to be fairly aggressive with this, and choose a value of 2EV typically.
If using a 3 shot bracket as we set up above, this means we’ll get one photo at the metered exposure, one underexposed by 2EV and one overexposed by 2EV. This is a pretty good range for most situations, and should allow us to produce a great HDR photo in most cases.
i) While continuing to hold down the BKT button (see above), rotate the subcommand dial to set the exposure increment. Choose 2.0 if you want to go with my recommendation of a 2EV increment.
Step 5: Go ahead and shoot!
It’s pretty much a must to use a tripod when shooting HDR using exposure bracketing. Since we want to combine data from multiple images, we don’t want any movement in between the different exposures. Setting up on a tripod will help to keep everything steady.
When you press the shutter release button, if all goes according to plan, the camera should take several shots in a row depending on the number we set above. These are all stored as separate images on the camera — there’s nothing special about the photos themselves at this point, only the method we used to take them.
Now that we have several photos of varying exposures, we need to combine them into a single HDR photo using a computer. There’s many different software packages available to do this. One of the most popular is a package called Photomatix. Another option, and the one I’m going to show you next, is Adobe Lightroom.
NEXT STEP: How to use Lightroom to create HDR photos