Adjusting second monitor brightness?

roygbiv · 2011-08-12 19:48:19

I'm currently playing around with a dual-monitor setup with my laptop and a crappy dell monitor, using xinerama :

$ xrandr --output LVDS1 --mode 1280x800 --output VGA1 --mode 1280x1024 --right-of LVDS1

The only thing is that when I set the brightness, using either /sys/class/backlight/acpi_video0/brightness or xbacklight, only my laptop screen is affected. I noticed both screens have the same $DISPLAY variable so I can't use that one to maybe choose one of the screens with xbacklight -d option. Is it not possible to adjust the external monitor brightness other than physically pushing the buttons on it? Please point me in some direction. Thanks

stqn · 2011-08-14 14:55:56

Probably not what you want but redshift has a "-b" (brightness) option and is supposed to handle multiple monitors. (redshift will not tell the monitor to change its brightness, but rather tell the graphics card to lower the brightness... for a different result I suppose.)

Edit: the command line would look something like:

redshift -l 45:5 -t 6500:6500 -b 0.5

Last edited by stqn (2011-08-14 14:59:04)

roygbiv · 2011-08-14 19:26:03

Nice! It worked using redshift. How do I find my geo location coordinates to use with it, so it is adjusted according to my location?

stqn · 2011-08-14 20:27:20

https://duckduckgo.com/html/?q=How+do+I … oordinates should get you started .

Arch Linux

#1 2011-08-12 19:48:19

Adjusting second monitor brightness?

#2 2011-08-14 14:55:56

Re: Adjusting second monitor brightness?

#3 2011-08-14 19:26:03

Re: Adjusting second monitor brightness?

#4 2011-08-14 20:27:20

Re: Adjusting second monitor brightness?

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