Brightness Up (External Display) - Not working

Hi @Andreas_Hegenberg, I setup a CAG to dim the MacBook brightness and increase the external monitor brightness. Unfortunately, both Brightness Up (External Display) and Set Display Brightness don't work. The CAG is triggering though.

On BTT 4.587
macOS macOS 14.5

This only works if the external display supports display brightness changes via the Apple standards. Does it work with the default Apple brightness keys?

Yes it works

then at least the "Brightness Up (External Display)" action should work, as that one basically just presses these keys.
Are any modifier keys pressed while the CAG is activated? (pressing the brightness up key might not work if e.g. opt is pressed)

No modifier keys pressed. See the image I posted above, the Brightness Down is working (it's gets triggered on both MacBook and external display - display is mirrored). But Brightness Up (External Display) doesn't trigger. I also put in a delay to make sure, but didn't work

that's very weird, are you sure the standard keys work for your external display? (ctrl+brightness up)
I haven't had issues with monitors that integrate with the macOS brightness feature (using that myself often) ;-/

When I press F2 (brightness up button) on my keyboard, the brightness of both my MacBook and external display increases. Same with F1 for brightness decrease.

M2 MacBook pro

interesting, what kind of display is this?
Usually external displays need ctrl+brightness key to adjust their brightness.

In your case you should change the "Brightness Up (External Display)" to a standard "Brightness Up" action.

My MacBook is mirrored to my external monitor.

⌃ + brightness key doesn't even work. Just F2 works fine.

Monitor: LG, similar to this but not exactly (can't find model no right now)

very interesting, maybe in mirroring mode it behaves like this. I have never tried that :slight_smile:
Anyways, in that case the standard "brightness up" action (without 'external display') should work.

In general the set display brightness action only works if macOS shows a brightness slider for the display in System Settings, however this could also be different in mirroring mode.

But just "brightnes up" doesn't solve the thing I want. So basically when the CAG gets triggered, I want to increase the brightness of external monitor and dim the MacBook display brightness. "Brightness up" increases it for both :slightly_frowning_face:

unfortunately I don't think there is a way to achieve that with BTT alone.

Personally I use an app called "BetterDisplay" which is very powerful for managing displays and their brightness.

I have that app, but I'm not sure how do I achieve this with that? Mind sharing if you know

It supports all its operations via a command line interface. For example

/Applications/ set --brightness=50% --targetUUID="37D8832A-2D66-02CA-B9F7-8F30A301B230"

You can get the display uuid in the BetterDisplay settings under "Displays => Display Information"

Such commands can be triggered e.g. via BTT's "Run terminal command" actions.

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Ok, this seems to be working, but the CAG deactivation doesn't seem to trigger. i basically want to make brightness 100% in built display when the monitor is disconnected

seems the CAG condition is false here, but deactivation not triggering

list of terminal commands is the same for grou activation (which works) except the brightness is set to 100% for built-in display. Works in terminal. Also the HUD for deactivation doesn't show up, shows up for activation

@Andreas_Hegenberg need this last help on this ^

does the active screen resolutions variable change when in mirroring mode? Or is it the same whether the monitor is connected or not?

It does change


not mirroring

@Andreas_Hegenberg could you please help with this ^

I tried with my displays but any resolution change triggers the correct events immediately.

Are your CAG Activated and CAG Deactivated triggers set up at the "All Apps" level?