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I found this video to visualise what tone mapping is trying to achieve, and why "photorealism" is hard to achieve in computer graphics: https://www.youtube.com/

I found this video to visualise what tone mapping is trying to achieve, and why "photorealism" is hard to achieve in computer graphics: https://www.youtube.com/watch?v=m9AT7H4GGrA https://www.youtube.com/watch?v=m9AT7H4GGrA And I indirectly taught me how to use the exposure feature in my iPhone camera (when you tap a point in the picture). It's so that you choose the "middle gray" point of the picture for the tone mapping process, using your eyes which have a much greater dynamic range than a CCD sensor. TIL.

akomtu 1y ago
I've heard a good point that our eyes have, in fact, a boring 1:100 range of brightness. Eyes can rapidly adjust, but the real game changer is our ability to create an image in our video memory, which has an unlimited brightness range. Eyes give us maybe a 2d uint8 framebuffer, but our mind creates and updates a float32 3d buffer. This is why this experience cannot be reproduced on a screen.
- hnuser123456 1y ago
  If our eyes can only see 100:1, why is OLED taking off? LCD has been claiming 1000:1 for decades
  - __alexs 1y ago
    In my case it's because the motion clarity of OLED is excellent.
  - perching_aix 1y ago
    Because of fast & per-pixel level light control. Though this is true even if we completely ignore whether human eyes actually manifest a 100:1 auto-adapting dynamic range window.
amarshall 1y ago
> the exposure feature in my iPhone camera…choose the "middle gray" point of the picture for the tone mapping process No, it uses that to set the physical exposure via the shutter speed and ISO (iPhones have a fixed aperture, so that cannot be changed). It literally says this in the video you linked. This is not tone mapping. Tone mapping in a way may also happen afterwards to convert from the wider dynamic range of the sensor if the output format has a more limited dynamic range.

akomtu 1y ago

I've heard a good point that our eyes have, in fact, a boring 1:100 range of brightness. Eyes can rapidly adjust, but the real game changer is our ability to create an image in our video memory, which has an unlimited brightness range. Eyes give us maybe a 2d uint8 framebuffer, but our mind creates and updates a float32 3d buffer. This is why this experience cannot be reproduced on a screen.

hnuser123456 1y ago
If our eyes can only see 100:1, why is OLED taking off? LCD has been claiming 1000:1 for decades
- __alexs 1y ago
  In my case it's because the motion clarity of OLED is excellent.
- perching_aix 1y ago
  Because of fast & per-pixel level light control. Though this is true even if we completely ignore whether human eyes actually manifest a 100:1 auto-adapting dynamic range window.

amarshall 1y ago

> the exposure feature in my iPhone camera…choose the "middle gray" point of the picture for the tone mapping process No, it uses that to set the physical exposure via the shutter speed and ISO (iPhones have a fixed aperture, so that cannot be changed). It literally says this in the video you linked. This is not tone mapping. Tone mapping in a way may also happen afterwards to convert from the wider dynamic range of the sensor if the output format has a more limited dynamic range.