High Dynamic Range Imaging (HDRI or HDR) has been around for a while – but I only just discovered the techniques in the last few days. You’ve probably have seen a ton of images with that uses these techniques and wondered how did they get that shot. In my case, my very desktop wallpaper was an HDR image — it’s actually the first image in the Wikipedia article, and I didn’t even know it!
I discovered HDR from a new Podcast that I’ve subscribed to at This Week In Photography. 
Check them out as they have a number of great tutorials.
In any event, HDR images are basically images that created from either a single image or a combination of multiple images compiled together. The object is to create an image where the shadows of one image is lighten up by the images of another picture. In addition, any “blown out” parts of an image can be modified to be correctly exposed from other images.
Say for instance that you are taking a picture of someone indoors standing with their back to a window and it’s a sunny day. If you expose the person correctly, the image will have the contents of the window “blown out”. If you expose the contents of the window correctly, your subject would appear as a silhouette. If you use some HDR techniques, you can combine the two pictures so that you see both the contents of the window and your subject at the same time with perfect exposure.
Fortunately, there are a number of applications on the marketplace that will do this for you automatically. Adobe’s Photoshop comes with a built-in function that will do this. You’ll find it under File\Automate\Merge to HDR. Another very popular standalone product that performs this type of work is Photomatix from HDRSoft. It runs for $99 USD, but seems to be worth the money if you take a look at an example of what it can do: (this is from their site)
Once I saw how some of these images were being captured, I immediately went to my User Manual for my D80 Nikon. I HAD to learn how to set up shots for exposure bracketing. Now I can’t wait for the opportunity to get some images into a HDR format.
-JT