Is HDR the Same for Video and Photography?

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A Does the metadata used to enhance video for high dynamic range TVs also work with still photographs? —George Yeoh / via e-mail

Q No. Two very different processes are used to create HDR (high dynamic range) video and photos. With HDR video, images are captured at 10-bit or higher resolution using a professional digital cinema camera. During HDR post-production and mastering, metadata is added to the content that triggers an HDR-capable TV to display the expanded contrast and color gamut captured in the original image. If the TV being used is not HDR capable, the metadata gets bypassed and the set displays a standard 8-bit image with a Rec. 709 (HDTV) color gamut.

With HDR photography, multiple versions of an image are taken at various exposure levels and combined by a smartphone app or software package (Photomatix or Luminance DR, for example) to create a composite image. The key difference between high dynamic range video and photos is that an HDR photo isn’t real HDR: the increased shadow and highlight detail is instead an HDR-like effect created by the merging of multiple images with different exposure levels. That’s why if you were to display a photo created using an HDR photo app or software on an HDR-capable TV, it wouldn’t have the same dynamic visual quality as HDR video.

COMMENTS
utopianemo's picture

It should be theoretically possible to encode such photos in HDR, shouldn't it? I've heard it said a number of times from various AV media sources that it is possible to grade old films in HDR, since the number of f-stops used in 35mm-70mm film and up is significant enough to produce an extended dynamic range(that has heretofore been beyond the reach of standard Blu-Ray). Case in point: The new Blade Runner HDR release on HD Blu-Ray has been widely praised in the media for its excellent HDR.

I know I'm going down a bit of a rabbit trail from the poster's original question, but if old film has the potential for HDR grading, I wouldn't think it too far off that a high-resolution digital image from something like a Canon or Nikon SLR in "HDR" mode could similarly be coded to show up in HDR10 or something similar.

WildGuy's picture

i never thought about it but even if i thought about it, i thought hdr for both still pictures and videos are the same, if not the same, then similar. Its not until i read this topic is when i realize they are different. interesting. good to know.

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