For many exposure bracketing shooting situations, the photographer just wants to ensure a photo with proper exposure is captured without worrying too much about the slight movements between the shots since other over or under exposed photos will most likely be discarded. For HDR photography, the requirements are more strict. Every photo counts for the quality of the final image. You should try to avoid anything that may cause blurring in the merged image. What does this mean?
- Shoot on a solid tripod and lock down the the tripod head. This is easy to understand. In practice, however, there may still be some vibrations from the photographer fumbling on the camera or the mirror slap in SLRs. The best ways to control this is to use a remote shutter release and use the mirror lock-up (why?), or shutter release delay function if you camera has them.
- Put the camera in manual focus mode. You can try to auto-focus first then change to manual focus mode. The purpose of this is to make sure there is no change in the lens focal point in the shots.
- Use manual or aperture priority shooting mode. This makes sure the aperture does not change during the shooting. Changing aperture means changing depth of field (DOF). Merging photos with various DOF is undesirable in HDR photography.
- Watch out the light. If the light change rapidly, such as in a cloudy day, try to finish all the shots in a short period of time.
- Have enough differences in the exposure. EV step less than 1EV is mostly useless. Try +/-2EV to begin with. In case your camera cannot do +/- 2EV exposure bracketing (Nikon D200 can only do bracketing with maximum 1EV per step), you may need to take more shots (eg. 5 shots at 1EV/step on D200) or use manual exposure bracketing.
- Shoot RAW to capture more details. Raw files have more bit depth than JPEG (12bit or more vs. 8 bit), therefore contains more luminance and color details.
- Use lowest ISO possible. This is for the best noise performance and the largest dynamic range.
If you find these tips useful or want to share your experience, please feel free to comment below.
Keywords: HDR, High Dynamic Range