When to Shoot Single Exposures for HDR Photography
You need to know when and why to shoot single exposures for high dynamic range photography. This assures that you choose the right tool for the job, given the gear you have and the circumstance you’re in.
When to shoot single exposures for HDR basically boils down to movement:
You’re moving. If you’re moving around, you can’t always take bracketed photos. If you have a fast-enough camera and AEB, you might be able to get off three shots without blurring or alignment problems. For the most part, though, you won’t be able to.
This isn’t the same as standing still and taking hand-held, bracketed HDR. You can get off good brackets in that case — if you have a high frame rate (3 frames per second [fps] is adequate but 5 fps is very nice to have) and use AEB.
You might think the solution to this is to always use a tripod or monopod (easier to manage but not as stable). That might be true. Sometimes, however, that’s impossible. This situation is illustrated in the figure, where the photo was taken from inside a train ride.
Although you're reasonably stable and holding the camera steady, sometimes there is enough motion in the scene to make bracketing pointless. No camera can take bracketed photos of the scenery rushing past.
The subject is moving (or can’t be still). The other circumstance that will push you out of your bracket-shooting comfort zone is when your subject is moving: say, when you’re photographing people or animals. You might be standing still and have your camera mounted on a sturdy tripod, but if the subject is moving, you won’t be able to get off brackets without enormous alignment problems.
This photo shows this situation in action. This beautiful horse was galloping too fast to make brackets possible in this photo.
You might want to shoot single exposures for HDR, though, in these circumstances:
Casual shooting: Maybe you’re out for a walk with your camera, exploring your neighborhood. You didn’t take your tripod with you, and you don’t have a camera with AEB and a fast frame rate (which makes hand-held HDR effectively impossible). Solution? Take photos in Raw and process them as single-exposure HDR.
This photo was taken at a Johnny Appleseed Festival while the photographer was sight-seeing. This is a perfect situation for casual photography and single-exposure HDR.
Bracketing problems: Say you did set your camera to photograph brackets and successfully completed the shoot, only to find out in software that you have problems, such as ghosting or something movement related, as shown in the figure. This close crop of a car moving away from the camera during the shot created ghosting, so the car appears in each bracket in a different position.
You can ignore these problems if you want and press ahead, or use single-exposure HDR to process one bracket to use as an overlay and freeze the situation.