Is “jailbreaking” our way to higher SDR brightness on the new miniLED Macs possible?

[collin_]

Okay, so as most of you are probably already aware, the new miniLED 14 and 16-inch MacBook pros can achieve an incredible 1,000 nits of fullscreen sustained brightness. The catch is that that‘s only available while HDR content is onscreen, which for most people is like 0.1% of the time.

When HDR content is not onscreen, you’re still limited to the same 500 nits, which goes all the way back to the 2016 models. As someone who always has my brightness maxed out and often finds it to still be insufficient, this is super disappointing to me. I thought we would at least get 600 like the miniLED iPad Pro has, which uses the same display technology from the same manufacturer. ._. I have both a 500 nit Mac and a 600 nit iPad Pro and believe me the difference is way more noticeable than you would expect.

Given that these are Macs and we have a much higher level of control over the system compared to something like an iPad, would it be theoretically possible to “hack” our way to higher fullscreen SDR brightness? If so I would love to just raise it to 600, and I’d happily take the battery hit. It seems like something that may be possible given that this is a simple artificial limitation, but I need someone with a deeper understanding of macOS to weigh in.

 

[altaic]

Interesting. I was also surprised by the standard brightness spec— though, in my use, I don’t need even the full 500 nits.

But, I was thinking about the possibility that the reports of ghosting (i.e. lcd hysteresis, which I barely perceive on my machine) could be due to under driving the display. In that case, a firmware update or firmware (and possibly hardware) hack might remedy the situation, to the detriment of battery life. But what about component life?

Your question made me think about the design constraints. As far as thermals (and panel life) go, the MacBook Pro’s screen should be able to shed heat better than the iPad Pro— the MacBook’s screen has less thermal resistance to the back surface, which should greatly increase heat transfer. That should mean that the lifespan of the panel should be far better at equal brightness. And the display-demanding use cases are similar for both— a bright white web page might be viewed for hours on both. I had been thinking that HDR content will almost certainly not be as bright as web browsing, which is probably true, but also irrelevant because the iPad has a greater standard output of 600 vs 500 nits.

This leads me to the conclusion that either (1) battery life is everything (which is weird since the MacBook Pro has much larger batteries; it should just be a software hack, though), or (2) the display panel has better (unknown to me) physical properties and other worse (brightness and responsiveness) physical properties then the iPad’s display.

Contrary to your statement about the same technology from the same manufacturer, they are not the same panel, so I think it could be either 1 or 2… or some other number ?

 

[tastylemon]

I tried messing with the settings by going to System Preferences -> Displays -> Presets -> Custom Presets -> "+" icon at the bottom. It doesn't let me set the max brightness for SDR (standard dynamic range) past 500 nits. If I put in 600, it truncates the value to just "60". I can't even do "501".

 

[tastylemon]

It's also possible that you might be able to bug developers to update their apps.

Personally, I'm not a fan of this option. When I want higher brightness, I want it across the entire system. It would be weird to have one app at 500 nits and another at 1000.

Apple has a video describing how developers can enable HDR in their apps.
https://developer.apple.com/videos/play/tech-talks/10023

There's nothing special about HDR vs SDR content when you're writing code to display pixels on a screen. However, this doesn't mean that you'll get access to it by default even as a developer. When it comes to saturation, as the displays went from supporting sRGB to P3, images displayed on macs didn't automatically get more saturated -- and that's a good thing. For example, when it comes to high saturation punch colors (wide gamut), as a developer you need to explicitly opt in to each color in your app or website individually:
https://webkit.org/blog/10042/wide-gamut-color-in-css-with-display-p3

 

[collin_]

I tried messing with the settings by going to System Preferences -> Displays -> Presets -> Custom Presets -> "+" icon at the bottom. It doesn't let me set the max brightness for SDR (standard dynamic range) past 500 nits. If I put in 600, it truncates the value to just "60". I can't even do "501".
View attachment 1880944

This is useful information to have, thank you. Yeah I figure that if this is possible it’s going to take some sort of terminal command or modifying a system configuration file or something.

 

[altaic]

I tried messing with the settings by going to System Preferences -> Displays -> Presets -> Custom Presets -> "+" icon at the bottom. It doesn't let me set the max brightness for SDR (standard dynamic range) past 500 nits. If I put in 600, it truncates the value to just "60". I can't even do "501".
View attachment 1880944

Really interesting. I ran `defaults read` but it didn’t turn anything promising up.

However, I did notice that you can export the display profile to a plist file, edit it, then reimport it. I haven’t personally tried going over the defaults, though, since I don’t need it myself.

 

[heinzdembowski]

Are there any IDEs text editors that are HDR enabled? Then there wouldn't be any need for hacking and it could potentially save battery life outdoors when using white on black for example.

 

[tastylemon]

I wonder if the brightness limit is partially there to limit blooming. If so, SDR is limited from 0-500nits because that level of contrast wouldn't show noticeable blooming. However, if you have a dark-mode window next to a light-mode window and one is 1000 nits and the other is 0, then it may be too much.

I just tried this test:

The display looks fine with the brightest white next to the darkest black. However, I'm not sure how small bright text will look on a black background and vice versa. It has 10,000 zones so that's a 100x100 resolution. I don't expect small features to be able to get bright without some crazy blooming. So I can sort of see why they might want to limit the max brightness.

For outdoor usage, I mostly care about brightness and reflections. So raising the brightness floor would be interesting. Suppose you the darkest black is limited to 300 nits and the white is 1000 nits. This is a bad idea indoors, but it might work well outside in bright sunlight. I wonder if Apple might introduce an outdoors mode or if something like this becomes a 3rd party app.

 

[tastylemon]

Really interesting. I ran `defaults read` but it didn’t turn anything promising up.

However, I did notice that you can export the display profile to a plist file, edit it, then reimport it. I haven’t personally tried going over the defaults, though, since I don’t need it myself.

I updated the 500 to 1000 and tried importing it

 

[altaic]

I updated the 500 to 1000 and tried importing it

View attachment 1881083


View attachment 1881077

Ah, not too surprising. I wonder where the range values are stored. Maybe the display driver? Or in CoreGraphics? I may poke around to satisfy my curiosity...

 

[collin_]

I updated the 500 to 1000 and tried importing it

View attachment 1881083


View attachment 1881077

Damn :/ I wonder if there’s any way to override it. I’m assuming you get the same error for 600?

 

[m0dest]

Wanna see a whiter white?

Wanna see a whiter white? CSS trick/bug to display a brighter white by exploiting browsers' HDR capability and Apple's EDR system

kidi.ng

Does that page work in Safari on the M1 Pro/Max models with XDR displays?

I have a feeling that the trajectory here is going to be ugly. First, it'll get hacked into web browsers. Then, it'll get hacked into text editors and other developer tooling. At some point, it'll just get too silly – Chrome Gmail in HDR, but Apple Notes in SDR – and Apple will relent, allowing full brightness levels for specific non-media scenarios.

Personally, I want those 1000 nits when I'm sitting outside and doing some boring stuff. I don't think that's crazy.

 

[altaic]

Does that page work in Safari on the M1 Pro/Max models with XDR displays?

Wow, yes indeed-- 16" M1 Max MBP

 

[alchemistics]

Call me genius but shouldn't it be theoretically possible to have something similar like the Tool "Work at Night" but working the opposite way around.

"Work at Night" will ad a grayscale Layer on top of your system and therefore allows for a very dim look.

In this case we'd need an App which adds an invisible or mirror HDR Layer over the system, therefore tricking the screen to a higher brightness.

I.e. in Mission Control you will see the layer as an actual application and therefore you'll loose the effect there. But that's a compromise I'd take.

Let's see if this idea has any potential application.

 

[Chancha]

Except that greyscaling simply asks for a lower RGB value.

Whereas engaging HDR needs a hardware limit to be lifted probably in the firmware level.

 

[Dividinho]

Wow, yes indeed-- 16" M1 Max MBP

Interesting... It doesn't seem to work on my 14" M1 Pro MBP. Did you adjust your display settings?

 

[matram]

Looking at the HTML source it seems the web page only applies a filter, reducing the brightness of the background.

This the title appear brighter. I have not dug out my colorimeter but I doubt we are seeing a brighter white, or?

 

[januarydrive7]

Looking at the HTML source it seems the web page only applies a filter, reducing the brightness of the background.

This the title appear brighter. I have not dug out my colorimeter but I doubt we are seeing a brighter white, or?

I may be looking at different html source:

According to their docs, there are HDR videos playing in the background, which cause the display to move to HDR mode.

 

[altaic]

Interesting... It doesn't seem to work on my 14" M1 Pro MBP. Did you adjust your display settings?

Nope. You can also see the difference in HDR YouTube videos. Just search for HDR. I’d never witnessed HDR like this before.

 

[leman]

Wanna see a whiter white?

Wanna see a whiter white? CSS trick/bug to display a brighter white by exploiting browsers' HDR capability and Apple's EDR system

kidi.ng

Does that page work in Safari on the M1 Pro/Max models with XDR displays?

It should work on pretty much any reasonably modern Apple device (on pre-XDR Macs Apple fakes HDR by manipulating the brightness).

Regarding the rest, Apple has long set on 500nits as a „reasonable“ max brightness for a personal computer monitor. The extra brightness is there not for outdoor operation but for wider color gamut.

 

[Diversion]

Jailbreaking won't help the SDR side of things.. the issue is the amount of power running to the LED board to power the LEDs.. The reason why HDR content is able to get up to 1600 nits is because it's not 1600 nits at every single 10,000+ LEDs, it's limited by the amount of individual zones that can get that bright while keeping the wattage to the LED controller at a point without burning it up to a crisp. Hope that makes sense. This is why we're hardware capped at 500~ nits on non-HDR content, it's the max sustained power that the LED controller can safely handle.

 

[tastylemon]

Jailbreaking won't help the SDR side of things.. the issue is the amount of power running to the LED board to power the LEDs.. The reason why HDR content is able to get up to 1600 nits is because it's not 1600 nits at every single 10,000+ LEDs, it's limited by the amount of individual zones that can get that bright while keeping the wattage to the LED controller at a point without burning it up to a crisp. Hope that makes sense. This is why we're hardware capped at 500~ nits on non-HDR content, it's the max sustained power that the LED controller can safely handle.

For 1600 yeah but what about the advertised 1000 nits sustained?

Are you telling me that pausing this video when it's displaying 1000 nits is going to destroy my computer?

 

[heinzdembowski]

I listened to a German podcast today where the guy said he put a screenshot of his desktop into an FCP HDR project and could switch between a nice 1000 nits version and his actual desktop on another space.

So yes, it's technically completely possible, maybe not ideal to display a completely white image, but I don't see why there should be on average more bright stuff on a desktop than in some HDR movie.

 

[tastylemon]

I listened to a German podcast today where the guy said he put a screenshot of his desktop into an FCP HDR project and could switch between a nice 1000 nits version and his actual desktop on another space.

So yes, it's technically completely possible, maybe not ideal to display a completely white image, but I don't see why there should be on average more bright stuff on a desktop than in some HDR movie.

Would be cool if you have a video or a screenshot.

I don't have FCP. I imported a screen recording into iMovie but I don't think there's a way to artificially increase the brightness.

 

[nicetriangles]

Jailbreaking won't help the SDR side of things.. the issue is the amount of power running to the LED board to power the LEDs.. The reason why HDR content is able to get up to 1600 nits is because it's not 1600 nits at every single 10,000+ LEDs, it's limited by the amount of individual zones that can get that bright while keeping the wattage to the LED controller at a point without burning it up to a crisp. Hope that makes sense. This is why we're hardware capped at 500~ nits on non-HDR content, it's the max sustained power that the LED controller can safely handle.

This was my thought. Even if it was physically possible I suspect it would be bad for the hardware.