Exposure Bracketing Stops

Exposure bracketing in stops

When you bracket exposure, you shoot the same scene a few times at different exposure values (EV). Afterward you can keep whichever frame looks best, or blend the lot into a high-dynamic-range (HDR) composite. Most photographers run 3, 5 or 7 shots, stepping by ±1 or ±2 stops between frames. A five-shot run looks like -2, -1, 0, +1, +2 EV.

Recent Sony, Canon and Nikon bodies ship with Auto Exposure Bracketing (AEB). Hold the shutter and the camera fires the whole burst for you. From there you bring the frames into Adobe Lightroom (HDR Merge), Photomatix Pro, Aurora HDR or Affinity Photo, where the merge pulls detail back out of the deep shadows and the blown highlights at the same time.

Applications

Think wide-contrast landscapes at sunrise or sunset, backlit forests, real-estate interiors with bright windows blowing out, buildings shot against the sky, and astrophotography foregrounds. In all of these the scene holds more dynamic range than the sensor can grab in one exposure.

FAQ

How many shots do I need? For most landscapes, three frames at ±2 EV are plenty. Reach for five or seven when the contrast is brutal, like the sun sitting right in the frame, or when you need to balance a dim interior against a bright view outside.

Should I bracket aperture or shutter? Bracket the shutter speed. Leave the aperture alone, because changing it also shifts the depth of field, and then your frames won't line up when you try to merge them.

Do I need a tripod? You really want one. Lightroom and Photoshop can auto-align the frames, but a solid tripod still gives you cleaner merges and keeps moving subjects from ghosting.