M1 MacBookPro 14_Lid being open allows external display to be brighter.

Working on sound for TV. Picture is dark and need to see action on screen to cut sync FX. Raised brightness as much as I could but details still lost in shadows. Thought maybe I could just look at this section on the M1 MBP screen and when I opened the lid the external monitor got brighter. Bright enough to see the details.


If I close the lid the external monitor returns to it's previous "lower" brightness level.


External monitor is the

LG UltraGear 34GK950F-B 34" 21:9 Curved 144 Hz FreeSync IPS Gaming Monitor


Connected via thunderbolt to Display Port 1.2


If I change the monitor to Display Port version 1.4 the brightness stays at the lower level no matter what I do.


I don't need an answer as to why this happens but I am curious if anyone happens to know.

MacBook Pro (2021)

Posted on Sep 13, 2023 9:12 AM

Reply
1 reply

Sep 14, 2023 8:52 AM in response to Eric Strausser

Greetings Eric Strausser,


It looks like you're on a Mac using macOS Monterey. That being said, here are a few settings you can look over for that macOS version to see if it is affecting your external display.


To change these preferences, choose Apple menu  > System Preferences, then click Displays . When your Mac is connected to a display, choose Apple menu  > System Preferences, click Displays , then click Display Settings.


When you're in the Display Settings, check to see if your external display is set to be the primary display. If it is not, change it by clicking and selecting it, and see if this helps to correct the issue with the brightness on the display.


If this does not help, try using a different cord to connect the Mac to the display and see if this helps to resolve the problem. Return to this thread with the results, so if you need more help others in the Apple Support Communities can jump in and guide you.


We hope this information helps you out.


Cheers!

M1 MacBookPro 14_Lid being open allows external display to be brighter.

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