Today’s Question: How many photos do you recommend capturing when bracketing for HDR [high dynamic range]? And how many stops should each photo be separated by?
Tim’s Quick Answer: How many frames you’ll need in a bracketed sequence will vary by the specific photographic situation. I recommend bracketing in two-stop increments and making sure that you have enough photos in that sequence to cover the full tonal range of the scene. That can require around five (or more) captures in extreme cases, such as when including the sun in the frame.
More Detail: There’s no need to bracket exposures for HDR by less than two stops between each exposure, so I recommend starting there.
If you’re going to use a manual process for bracketing by just adjusting the shutter speed for each exposure, for example, you can start with an exposure that is dark enough to retain the brightest highlight detail, and capture exposures in two-stop increments until you’ve brightened to the point that full shadow detail is revealed.
If you’re using automatic exposure bracketing, you need to make sure you’re bracketing enough to cover the full range of tonality in the scene. Some cameras only offer three exposures for automatic bracketing, so in some cases you may need to use a manual approach. But many cameras offer five, seven, or even nine frames for automatic bracketing.
Obviously, you could test to determine how many bracketed exposures you need, but especially if time is of the essence, you may find it is easier to just bracket at the maximum number of exposures available for automatic bracketing on your camera, and then delete any unnecessary frames later.