Remember screen brightness settings in Ubuntu and Linux Mint

Screen brightness is an attribute that is reset automatically upon rebooting your machine on Ubuntu and all its fellow distributions. Lucky you if you find the settings okay, but on notebooks and similar machines, you might want to lower the brightness, you it doesn't suck your batteries dry.

To do that, open the following file as root via terminal:

sudo gedit /etc/rc.local

In there, enter the following line somewhere before the very last one that says "exit 0":

echo 0 > /sys/class/backlight/acpi_video0/brightness

0 is the lowest brightness setting. You can adjust it to your likings!

4 thoughts on “Remember screen brightness settings in Ubuntu and Linux Mint”

  1. I have used this several times to lower my boot-up screen brightness to a comfortable level.Thanks.

    I don’t know if it is a new or unique feature, but this can also be done by using “open folder as root” feature in Mint 17 XFCE. I was able to make this change without using terminal. Go to “file system” and right click on “etc” choose “open folder as root” then open the rc.local file with text editor, make the change, close and save the file. Close file manager and on rebooting the new brightness level is used.

  2. Here is a line that will adjust the brightness as a function of the time of the day :

    echo “s( ($(date +’%H’)+18)*3.14/12 )*50+51 ” | bc -l | cut -d ‘.’ -f 1 > /sys/class/backlight/acpi_video0/brightness

    It uses a sine. 12h is brightest, 0h is darkest.


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