Single Shot HDR - or How to Save Underexposed or Flat Images Using Tone Mapping

Went out this past Saturday and found myself at Jamaica Bay National Wildlife Refuge at the end of the day. The weather had been threatening rain all afternoon, but I took the chance to go there anyway. Aside from a nesting pair of Osprey, and a flock of Brants feeding at the shoreline, there was the sky. That kind of sky that you see before or after a storm. Bits of blue in the cloudless areas, the warm color of a soon-to-set sun reflecting off the numerous clouds, and a totally clear view of the whole spectacle - but my sights were set on the Osprey couple.

So I snapped off a few pictures without thinking. When I viewed the images on my computer, they looked pretty sad. The sky was correctly exposed, but everything else was drab and dreary. This was not at all how I remembered the scene, so I started thinking about how I might restore the original "feel" in the image.

There are a number of tools that can help you recover an underexposed image - Lucis Art, Topaz Adjust, the built-in tone mapping available in Photoshop - but I decided to use Photomatix Pro - mainly because I like the quality of the output and the relative ease with which I can get those results.

For a full description on how to use Photomatix Pro, look at my blogpost here. The process with a single image is similar to the one you would follow for a multiple image HDR after you merged the images into a single image. Basically you have two main options - Tonemapping and Exposure Fusion. The Tonemapping selection has two choices - Details Enhancer and Tone Compressor. I find the following workflow useful:

1. After loading the image, select a preset that gets you closest to the "look" you are trying to achieve.
2. Use "Strength" at close to 100% to  control how contrast will be affected by the subsequent adjustments.
3. Set white point, black point, saturation and gamma to please your eye.
4. Start making adjustments using smoothing, micro smoothing, contrast, microcontrast, luminosity etc - until you have gotten closer to your goal. 
5. If you end up with halos, use highlight smoothing to remove them.
6. Save and open the image in Photoshop - make whatever cropping, tone, contrast, color balance, sharpening and noise reduction adjustments you typically make. At this point you should be done. 

I have included several before and after examples below.