new M3 Max - display randomly dims and brightens in Develop module

[gregde]

I got my new 14" MacBook Pro with M3 Max and I'm immediately seeing the following behavior on both Classic and Cloud-based LR. When I go into the Develop module, the entire UI randomly dims and brightens as my move my mouse around. Disabling GPU acceleration fixes the problem.

LR Version: 13.0.1

OS: 14.1.1

Anyone else experiencing this?

[gregde]

Attaching LR sys info

[johnrellis]

Just a guess: In Mac OS System Settings > Displays, try turning off Automatically Adjust Brightness and True Tone.  Maybe that feature is interacting badly with LR's use of the graphics processor.

Also, verify you have Preset: Apple XDR Display (P3-1600 nits) selected.

[gregde]

Thanks for suggestions. Tried them both and made no difference. 

Just to be clear - it's just the image (and background panel) that dims and brightens. The rest of the display (other LR panels, menu bar, other windows) stays the same. 

[Philip555]

Yes tried both suggestions but no difference.

[gregde]

Following up to my own post - turns out this only happens when a Pro Display XDR is connected. Works fine on both the built-in laptop screen and a Studio Display.

[gregde]

Looks like this is the same issue described here: https://community.adobe.com/t5/lightroom-classic-discussions/m2-max-lrc-external-monitor-develop-mod...

The workaround described there - make sure brightness of the Pro Display XDR is "two clicks" below full - also works for me. 

It's still definitely a bug in LR but at least I can use my laptop. 

[lky99y]

Glad I found this.  The camera raw window in photoshop dims as well.  Just got a new M3 Max laptop and the adobe windows are dimming on me with my XDR monitor when my 5 year old machine would not.  I found if the brightness of the XDR was set about 1 cm from max brightness the adobe windows wouldn't dim.  Sidenote, why isn't there a more precise quanitifiable way to handle brightness for these expensive monitors??

[Ian Lyons]

The issue described above also occurs in multiple non Adobe applications when external displays are connected to Apple Silcon  based Macs. BenQ (see link below) , Eizo and multiple others display vendors provide suggestions as to minimise the issue. To date, nobody, which includes Apple, has put forward a definitive fix. Lots of workarounds, but no actual fixes.

https://www.benq.eu/en-uk/knowledge-center/knowledge/how-to-fix-mac-m1-m2-external-monitor-flicker.h...

[Ian Lyons]

Here's a link to a thread on MacRumors

https://forums.macrumors.com/threads/mac-studio-screen-flickering.2338756/

[Jao vdL]

Full brightness setting is FAR too bright on those systems even in very brightly lit rooms. You will be editing all your images to be far too dark. You can limit the maximum SDR and HDR brightness of these screens by creating a custom preset setting in the display preferences. Standard for image editing is about 120 nits but in bright rooms you can go a bit higher. If you set maximum brightness, you get more like 500 to 1000 nits in SDR which will lead to images being edited far too darkly.

[Conrad_C]

Sidenote, why isn't there a more precise quanitifiable way to handle brightness for these expensive monitors??

By @lky99y

There already is. And for Apple Macs, that feature is exclusive to Apple displays with XDR in the name.

If you have an XDR display, it supports Reference Mode presets. One of the big reasons Reference Mode presets are so superior to the old ICC-profile-only display color control is that for the first time ever for Apple displays, you have precise control over luminance. (For many years, this was possible by connecting a Mac to a non-Apple professional display that supports hardware calibration.)

If you set it to the full range Apple XDR Display preset (the default, I think), it will allow for luminance headroom so that peak highlights can reach HDR levels. This preset is appropriate if you edit or watch HDR video, or if you want the display to reach the 1000+ nits required for the new HDR editing/previewing mode in Adobe Camera Raw and Lightroom/Lightroom Classic.

If you want to clamp the brightness so that previews are more consistent with limited brightness media such as print, you can choose one of the other Reference Mode presets that enforces a brightness limit.

If you want to customize that brightness limit or other settings, you go in and make your own Reference Mode preset. In the example below, I am creating a Reference Mode preset for a print workflow, specifying values that include limiting luminance to 110 nits for better print matching, and I have shut off Enable HDR Content.

I do not know how any of this is related to the bug being discussed in this thread.