external_monitor_brightness_control.txt

Software brightness control

	xrandr -q | grep " connected"
	DP-4 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 527mm x 296mm

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Direct Hardware Brightness control

https://wiki.archlinux.org/title/Backlight#External_monitors



	sudo apt install ddcutil
	sudo ddcutil capabilities | grep "Feature:10"
	sudo ddcutil getvcp 10
	sudo ddcutil setvcp 10 50

first 10 is feature number 50 is brightness.