2 ms·

I do the same. UHD Blu-Rays with HDR look terrible on my non-HDR 4K TV. The colours come out terribly 'flat', and no amount of tweaking the display settings is

I do the same. UHD Blu-Rays with HDR look terrible on my non-HDR 4K TV. The colours come out terribly 'flat', and no amount of tweaking the display settings is able to set it right. I'm careful to go with ordinary Blu-Rays instead. Ideally of course I'd rather a non-HDR UHD Blu-Ray but these are increasingly rare. You'd think the disc players would be smart enough to do a good job mapping HDR to SDR, but here we are.

gruez 5y ago
>You'd think the disc players would be smart enough to do a good job mapping HDR to SDR, but here we are. I suspect the reason is that SDR and HDR have separate color grading/correction applied, so it's basically impossible to automatically convert HDR to SDR. Or in other words, "automatic" conversion from HDR to SDR inevitably looks bad, so production studios manually redo the color correction for SDR.
- MaxBarraclough 5y ago
  > "automatic" conversion from HDR to SDR inevitably looks bad, so production studios manually redo the color correction for SDR Perhaps that's it. What happens if you point a camera at an HDR TV and view the image/video on an SDR TV? Would the colours look flat?
  - gruez 5y ago
    Probably a combination of washed out colors, blown out highlights, and weird color grading. Keep in mind that cameras basically have their own tonemapping algorithms (see: https://lux.camera/understanding-proraw/ https://lux.camera/understanding-proraw/) that presumably isn't magic, so you'd have the same problems that HDR -> SDR tonemapping has. Also if you search around there are also HDR -> SDR releases that purports to use some sort per-scene analysis to do better HDR -> SDR conversions. Based on the screenshots they definitely look better, but they're still different than the real SDR release.
    - MaxBarraclough 5y ago
      On the plus side, I've found that HDR-enabled UHD streaming services cope fine with 4K/SDR. I imagine they send an entirely different (SDR) stream in that case.
      - CarVac 5y ago
        Apparently not the HBO Max stream in the post that started all of this, which has ugly clipped highlights from an HDR stream served to an SDR display.
        gruez 5y ago
        Yeah, if you search around there aren't any 4K SDR releases for matrix 4. For a release this popular and this late after release, I'm guessing the reason is because it doesn't exist. The same applies to another HBO max exclusive, Dune. However, there are streaming services that have 4K SDR content (eg. Foundation from Apple TV), but it definitely seems to be the exception rather than the rule.

gruez 5y ago

>You'd think the disc players would be smart enough to do a good job mapping HDR to SDR, but here we are. I suspect the reason is that SDR and HDR have separate color grading/correction applied, so it's basically impossible to automatically convert HDR to SDR. Or in other words, "automatic" conversion from HDR to SDR inevitably looks bad, so production studios manually redo the color correction for SDR.

MaxBarraclough 5y ago
> "automatic" conversion from HDR to SDR inevitably looks bad, so production studios manually redo the color correction for SDR Perhaps that's it. What happens if you point a camera at an HDR TV and view the image/video on an SDR TV? Would the colours look flat?
- gruez 5y ago
  Probably a combination of washed out colors, blown out highlights, and weird color grading. Keep in mind that cameras basically have their own tonemapping algorithms (see: https://lux.camera/understanding-proraw/ https://lux.camera/understanding-proraw/) that presumably isn't magic, so you'd have the same problems that HDR -> SDR tonemapping has. Also if you search around there are also HDR -> SDR releases that purports to use some sort per-scene analysis to do better HDR -> SDR conversions. Based on the screenshots they definitely look better, but they're still different than the real SDR release.
  - MaxBarraclough 5y ago
    On the plus side, I've found that HDR-enabled UHD streaming services cope fine with 4K/SDR. I imagine they send an entirely different (SDR) stream in that case.
    - CarVac 5y ago
      Apparently not the HBO Max stream in the post that started all of this, which has ugly clipped highlights from an HDR stream served to an SDR display.
      - gruez 5y ago
        Yeah, if you search around there aren't any 4K SDR releases for matrix 4. For a release this popular and this late after release, I'm guessing the reason is because it doesn't exist. The same applies to another HBO max exclusive, Dune. However, there are streaming services that have 4K SDR content (eg. Foundation from Apple TV), but it definitely seems to be the exception rather than the rule.