What is HDR Photography? High-Dynamic-Range Imaging

Photographers toss around the HDR abbreviation, but exactly what is HDR photography?

HDR Definition

• HDR photography (high-dynamic-range imaging or HDRI) merges 2 or more high-contrast images of the same scene at different exposures. The resulting photo avoids blown out highlights and shadows.

For example, a mountain with the sun in the background would have a high-dynamic range. The mountain will cause a shadow making certain parts of the scene dark and the sun will make the other parts bright. This scene will have very bright and dark areas; hence, the high-dynamic range.

Human eyes are more advanced at seeing the dynamic range of a scene and its details compared to a camera. Cameras are not able to expose correctly for bright and dark parts of scene in one photograph; HDR (imaging or HDRI) photography assists with this problem.

HDR photography is a technique to capture the dynamic range of a scene. Generally, three photos are photographed using the camera’s AEB (automatic exposure bracketing) function: normal exposure, under exposure, and over exposure. The three bracketed photos will be merged into one image using HDR software.

The below three images show an example of AEB. Notice the constant aperture size of f/8.0.

Normal Exposure

Under Exposure

Over Exposure

The above three photos were merged in Photomatix to produce the below HDR photo, but prior to its final post-processing steps in Lightroom or Photoshop. Consider this a middle step in HDR post-processing.

Mobile phones are now offering HDR capture. The HDR images are decent quality and convenient when you don’t want to carry around a camera. For controlled, HDR photography, it’s better to use RAW capture with a mirrorless or DSLR camera, and post process.