Assistance Needed with Brightness Limitation After Adjusting Native Resolution via BetterDisplay

[yarenhere]

System & Software Details:

• Machine: MacBook Pro (M2 Pro)
• macOS Version: 15.4.1 (24E263)
• BetterDisplay Version: 3.5.4 Build 40449

Issue Details

• The monitor's native resolution is 3840×2400.
• When connected to my MacBook Pro, the default resolution is limited to 3840×2160, causing incorrect text scaling.
• Using BetterDisplay, I manually set the native resolution to 3840×2400, which fixed the scaling issue.
• New Problem: After this adjustment, the monitor's maximum brightness now appears significantly dimmer (around 80% of its original brightness). Notably, the monitor's own settings menu still displays brightness as "100%" (no visible limitation there).
• Suspected Cause: It seems BetterDisplay might be restricting the brightness output despite the monitor's firmware reporting normal values.

Questions:

How can I resolve this brightness limitation while retaining the correct resolution (3840×2400)?

What system/monitor information should I provide to help diagnose this issue?

Thank you for your time and support. Looking forward to your advice.

[waydabber]

Hmm. What kind of display is it? 3840x2400 seems interesting/unorthodox. Does the image take up more space than before? Isn't it related to some kind of brightness limiting on the display itself? If there is no software dimming involved and the OSD still says 100% (so no hardware luminance control is involved), then I don't see how overriding the native resolution could in itself cause a drop in brightness output.