On: Trying to get past the 500 nits limit of the MacBook Pro (and failing)

[fulafel]

If we have a monitor that has a brightness of 1600 nits, and whites of some content ("sdr") shows up much dimmer, the pixels the monitor is asked to display by the systmes are dimmed relative to max brightness - no?

[alin23 → fulafel]

Yes, that’s another way of putting it.

But people usually look at this, relative to previous displays, not relative to peak brightness (since the peak brightness is not achievable for prolonged periods of time because of overheating)

[fulafel → alin23]

Overheating sounds interesting! So what happens if you display a max brightness hdr image on the screen for a long time, does the monitor shut off?

Edit: apparently at least on some laptops your screen may automatically adjust brightness downwards if you are in a hot climate and the cooling system fails to keep up: https://9to5mac.com/2022/02/04/macbook-pro-limited-brightnes...

[alin23 → fulafel]

Yes, the system monitors the display temperature and caps the brightness accordingly. Here are some interesting functions I found related to this inside the system frameworks:

    SkyLight.framework:
        SLSDisplayIsThermallyLimited
    
    CoreBrightness.framework
        -[CBDisplayModuleSKL hasThermalMitigation]
        -[CBThermalBrightnessCap getCurrentCap]
        -[CBThermalBrightnessCap setJetMode:]