To one degree or another, we’ve all been underexposing our digital photographs, even if we’ve been exposing to the right (ETTR). Imagine a day when every ƒ-stop had as much data as the lightest ƒ-stop. It’s here now. Here’s how.
Make a series of bracketed exposures where each ƒ-stop in a scene is placed in the far right of the histogram or recorded with half the data in a single digital file. Combine all the exposures into a single 32-bit file using either the Merge To HDR Pro feature in Adobe Bridge/Photoshop or Lightroom. Save or import this 32-bit file into Lightroom (4 or higher) and apply adjustments with its Develop module to avoid many common tone-mapping artifacts.
You may be surprised to find that you’ll benefit from using this technique even for images with significantly more restrained dynamic ranges.