Down & Dirty HDR from the same image.
Wikipedia defines HDR as
In image processing, computer graphics and photography, high dynamic range imaging (HDRI) is a set of techniques that allows a greater dynamic range of exposures (the range of values between light and dark areas) than normal digital imaging techniques. The intention of HDRI is to accurately represent the wide range of intensity levels found in real scenes ranging from direct sunlight to shadows.
One would think HDR is a new technique, but not so…but there have been photographers exploring the layering of different exposures since the 1930’s. The advent of average joe’s like me who have photo processing software has produced this latest craze of everyone producing HDR images.
You can see some exaples on the Flickr HDR pool. I will post a few here…
image courtesy of rpeschetz
image courtesy of Zé™
Image courtesy of simone.garza
HDR is not foer every image and it is the hot technique right now, but as you can see by combining more than one exposure and then process by using tone mapping one can salvage a difficult to shot lighting situation.