What is High Dynamic Range Image (HDRI)

By Xah Lee. Date: . Last updated: .
New York City at night HDR
HDR image of New York. image source

Note how sometimes in a photo, parts are not detailed. You adjust contrast and brightness, but other parts becomes too bright or fainted out.

The solution, is to take several photos using different exposures, and then combine these photos into one. The result is is called High dynamic range image. The result is a image with high detail everywhere, which may make the image look artificial, but desirable for its detailed illustrative effect.

Example

the following are 4 images, taken with different exposure. Each one by itself is not great, but capture parts in detail.

St Louis Arch mult expEV-4.72 St Louis Arch mult expEV-1.82 St Louis Arch mult expEVp1.51 St Louis Arch mult expEVp4.09
(Photo by Kevin McCoy)

Combined Image

St Louis Arch mult expCDR
combined image. (Photo by Kevin McCoy)

Combined Image with Tone Mapping

St Louis Arch mult expToneMapped
combined image with tone mapping. (Photo by Kevin McCoy)