Tonemapping

Using the analogy of photography, if we were to photograph our scene using different exposure settings, then we could start to see these extreme color details which otherwise might have been lost. Light tones in the brightest areas of the image which have been lost to white can be recovered, or dark tones lost to black. This is analogous to ‘tonemapping’ in computer graphics, where we take colors outside of the range reproducible by our target device (computer screen, for example) and shift them mathematically into a range which can be reproduced. The resulting output still makes sense perceptually, because colors remain relative to one another. They are correct in context.

When using HDR cameras, the Tonemapping Image Effect from Standard Assets (Assets>Import Package>Effects) must be added to the camera. This script provides you control over how very bright color intensities recorded by your camera are converted into colors which can be displayed.

More information on Tonemapping can be found here.