Is it possible to set the default display brightness so you don't have to re-adjust it everytime you reboot? My laptop display is killing my eyes at the login screen already because it starts at 100% brightness every time.
Review of solutions and offering a (hopefully) better one
actually echoing some value to doesn't help in the brightness as the value will differ from system to system
first what you need to do is to set the brightness of the screen to the level comfortable to you, which can be easily done by in system settings --> brightness and lock or by using the function keys.
now go to the /sys/class/backlight/your_folder (mine was intel_backlight)
in this folder you can see hte actual_brightness file and the max_brightness file (don't forget to refresh the files Ctrl+R or F5 to see the actual settings if you have done any changes to the brightness after opening this file)
Now we need the same value as in the brightness every time we start our system this can be done by changing every time the value in this folder at the startup we need to change the rc.local file
first type this command in the terminal (can be opened by searching for terminal in the dash or by pressing the shortcut Ctrl+Alt+T)
and make sure that you add the line
Please replace the 900 value with what ever value you need (the value you get when see in the above procedure also the intel_backlight with what ever the folder name in the backlight folder)
the line rfkill block bluetooth was added in my rc.local file as I don't use bluetooth at all but ubuntu starts bluetooth everytime it reboots(even if the bluetooth was in off condition before), to avoid such thing I have used it. You can also add it (in case you wanted to use bluetooth you can always start it again even if this line is include in you rc.local)
Don't change the value of exit 0 in the ending if it doesn't exist just add it in the ending
Now even if you have restarted the system you will have the same value that you need (the value that you have given after the echo)
Be-careful don't give the value of brightness greater that max_brightness value as that will through you an error saying that it is an Invalid argument.
It isn't default. Whenever I reboot my brightness is set to 100%. Luckily I saw
and before that,
this works in my 12.04 How set brightness on startup – Ubuntu 12.04
every time i boot up, it is set already. hope it will help you.
This should do the trick:
Use the slider to adjust default setting.
Have you look at redshift? It's designed for another purpose (make the screen less bluish at night), but it might solve your problem as well.
My configuration file (
If you change brightness-day and brightness-night to a value you like and set temp-day and temp-night to the same value, you will effectively use redshift to set your brightness only.
protected by Community♦ Feb 13 '12 at 12:24
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