Today's post is going to tackle a tricky subject: High Dynamic Range (HDR)
Dynamic range is your camera's ability to expose both bright areas of a photo and dark areas of a photo. A camera with good dynamic range will give a photographer lots of wiggle room with exposure when processing images in Adobe Photoshop or Lightroom.
The best example of dynamic range is the human eye. Our eyes can look at a scene and it will look perfectly exposed because the human eye has an astounding range for processing different levels of light.
Take a look at the main photo for this post: The sky is perfectly exposed and so are the trees and grass in front of the camera. DSLR (Digital Single Lens Reflex) cameras, point-and-shoot cameras and even cell phones can sometimes tend to take an image that caters to the brightest part of a scene, leaving the darker areas of an image ... well, too dark.
Here's where HDR photography comes in.
There are a couple of ways to go about using this method of photography. The simplest way (and most limited way depending on your camera model) is to shoot in RAW format and hope that your camera has enough dynamic range to bring out the shadows and limit the more powerful highlights of an image. The above was processed this way and it turned out fairly well, however, this method isn't always an option if the source of light is too bright or if your camera doesn't handle very well under high-contrast situations like sunset or silhouette photos.
The second (and most popular) way to make an HDR image is to take several photos (using a tripod to limit something called ghosting) at different exposures and in post production merge them together. Most HDR photography can be accomplished with three images — an underexposed image, an overexposed image and an image that lies right in the middle of those two — but you can use more if necessary.
Why so many photos?
The underexposed image is so the brighter parts of the photo can be visible without being blown out. The overexposed image is so the darker areas of the photo can have their time to shine. Finally, the image taken at a normal exposure is to help balance out the two extremes.
When shooting the images, go under your camera's settings and look for AEB (Auto Exposure Bracketing). Turning this setting on tells your camera to shoot the three photos you need to merge an HDR image together. Then, once you get back to your computer, select the three photos in Adobe Bridge and go under Tools>Photoshop>Merge to HDR Pro. Photoshop will take it from there and allow you to play around with the exposure.
In general, HDR photography is really only done either for fun or out of necessity by photographers like myself. HDR photos can sometimes look a little goofy and a little bit grey if you don't get your settings right in Photoshop.
If you can shoot in RAW and your camera has enough dynamic range to make an image look great, I recommend using that to your advantage. If you're looking to play around with making some interesting images and you have the time to play with this concept, all the more power to you.
It can be a lot of fun.