I have taken the plunge into High Dynamic Range photography. Cameras cannot adjust for, nor capture the range of light that our eyes percieve. Exposure bracketing is a well-known technique whereby the photographer shoots three or more shots of the same thing – slightly changing the settings so that several types of exposure can be seen. With digital photography, these bracketed photos can be combined so that the best lighting from each image is used to form a single, well-exposed picture.
The Nikon D50 (and I’m sure the other Nikon DSLRs, as well) has two different bracketing modes. There is the traditional Aperture/Exposure mode, where three shots must be taken. In this mode, it’s best to use a tripod so that the same image is capture each time. Also, shots that include moving subjects will only produce a smear. The other mode uses White Balance, and automatically generates three images from one shutter click. This mode may not produce the same dynamic range as AE bracketing, but it will let you create HDR images that include motion.
Once you have several images, the next step is to combine or "stack" the images, then tone map them so that the best exposures from each image are used. This could be done manually with Adobe Photoshop, but is a pain in the posterior. Photomatix is a great program that automates these steps. I think the latest version of Photoshop CS has HDR capabilities, but I haven’t tried them.
Below are two images of the covered bridge over High Falls in Dupont State Forest:
The one on the top was shot in Auto mode with a bit of Photoshop post processing. The shot on the bottom is an HDR image. Note the details in the shadows on the woodwork. These can be seen much clearly in the HDR shot. One thing I have noticed is that clouds tend to turn out a bit darker. I’m sure this could be corrected in Photoshop, too.
Here is another comparison, this time using images of Hooker Falls:
I’m not saying the HDR shots are better, but they do give a different lighting perspective. I think the process lends itself to some interesting artistic effects. Some of my favorite shots are by local Flickr photographer NYTransplant:
To me, HDR lends an ominous feel to the image. I guess that’s because of the darkening of the clouds and sky. I won’t use it for all my shots, but it will be another interesting tool in my photo arsenal.
[tags] HDR, digital photography, Nikon d50[/tags]