asus389 if I'm not mistakened I think p3 panels all use ksf/pfs phosphor which could be the trigger too

      jordan if I'm not mistakened I think p3 panels all use ksf/pfs phosphor

      Yes, this. Wide-gamut panels seem to use alternative phosphors to get better red coverage, which seems (to me) to give the whole screen a reddish hue. When the screen causes discomfort even when in the background, not looking directly at it, then I have to suspect the backlight itself emitting an unhealthy light (although I suppose one could also argue another kind of unhealthy emission from the monitor/device, or flicker affecting the peripheral vision).

          I second this. I can use my sRGB 2015 MBP 15 with no issues. But anything newer with P3 causes symptoms immediately. I’ve tried Pro Air M1 M3, I even bought a 2019 MBP 15 (not 16) as it has the exact same res and PPI screen as my 2015. The 2019 caused symptoms immediately.

          The only thing I couldn’t test on the 2019 was Catalina (shipped with Mojave) so MacOS a possible factor, but I’m convinced it’s P3.

          I take it back a bit. I actually installed Catalina on the 2019 MBP 15" and it seems to be better. I need to sit with a bit more but at the least MUCH better than any of the Apple silicon machines or even the same 2019 MBP on Sequoia.

          I have real and definitely symptoms to every modern Mac.

          But is it possible most of this is due to MacOS after Catalina when they switched to lower contrast and softer text rendering? Is this all software instead of hardware?

            MAS-76 I do fine with Catalina also. Anything newer is worse, I have to modify settings and some apps still cause eye strain. My guess is it has to do with Big Sur and newer supporting P3 and HDR more aggressively in the UI, apps, and graphics apis. But I really don’t know.

              asus389 I mean you can change color settings but the leds still are using phosphor which cant be turned off. It will still emit the spectrum that the phosphor creates.

                The unfortunate part is it may be less a color/calibration issue and more a font rendering and low-contrast design issue, which I'm afraid will never be fixed - it's by design! Of course I'm sure there's hardware issues too, i.e. the P3 and 10-bit dithering aspects of it all. But after my 2015 MBP 15 is great on Catalina, and that same 2015 MBP 15 causes issues anything MacOS 11+ (albeit less than an Apple Silicon machine), I'm starting to believe MacOS itself is the main culprit.

                It's pretty discouraging.

                  MAS-76 Would these same issues exist on a true 10-bit panel that doesn't have to dither for P3 support? ie one of the recent Eizo CG monitors I think are not FRC? I don't know for sure though.

                    MAS-76 The issues getting worse on the 2015 15" with macOS 11 and later — point less to the design of the OS as the cause IMO — and more to the very likely case that newer AMD/Intel graphics drivers & firmware are provided with OS 11+ that render the image differently or change what graphics functionality is enabled by default.

                    If you look at a pixel-perfect screenshot of a modern macOS version, but on the older version that's working better for you, and it looks better than if that newer macOS version was running on the laptop itself — this would confirm the problem is the graphics drivers that are built-in to 11 and later.

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