Meter with AEB or Manual Mode in HDR
Using a preconceived bracketing strategy in high dynamic range (HDR) photography works well, but the downside is not knowing whether you’re really capturing the full dynamic range of the scene with the brackets (if you pay attention to a live histogram, you’re closer to knowing).
A more studious approach relies on metering highs and lows in the scene with your camera to come up with a more reliable estimate of how many brackets you should shoot.
You can use either Auto Exposure Bracketing (AEB) or manual mode.
Use AEB to bracket in HDR photography
If you’re using AEB, set the center exposure (0.0 EV) on your camera and configure AEB settings (if possible) to include the number of shots and EV difference.
Make sure to account for the entire dynamic range of the scene. In other words, if you need a spread of 6.0 EV evenly centered on 0.0 EV (+/-3.0 EV), you can shoot six brackets at +/-1.0 EV to cover the scene. If the spread is 7.0 EV (+/-3.5 EV from 0), you can shoot nine brackets at +/-1.0 EV or five brackets at +/-2.0 EV.
These examples cover the entire range. If your camera is limited by the number of brackets or the exposure distance between them, you can settle for the best it can do, or revert to manual mode.
If your AEB has the capability and you have set the number of brackets and EV range, complete bracketing as you would normally using AEB. You can stop here.
Use manual mode to bracket in HDR photography
If you’re using manual mode, follow these steps:
Set the shutter speed to the value indicated by your calculation for the low end of the dynamic range you wish to capture.
Although you can shoot them in any order you wish, it’s convenient to start at the underexposed end of the dynamic range and progress upward.
This figure illustrates the complete sequence, starting from low to high, including the shutter speeds.
Shoot the bracketed photo.
Increment the shutter speed to space the bracket by the EV distance you desire: for example, 1.0 or 2.0 EV.
Generally, three ticks of shutter speed equals +/-1.0 EV. Change by six ticks if you want to bracket by +/-2.0 EV.
Shoot another bracketed photo.
Plug and chug.
Continue incrementing shutter speed and taking bracketed photos until you progress from the low end through the center exposure (0.0 EV) and complete at the top end.
You finish with a complete, bracketed set of photos, as shown in this figure. This result is a five-bracket set at +/-2.0 EV for a total range of 8 EV. Using this method, you know that you accounted for the entire dynamic range of the scene.