How to make Unity remember brightness settings?

Question

This question has been asked many times for Ubuntu 11.10 but it always has been closed and linked with this link, but that accepted answer is from 2010 and that setting doesn't work anymore for Ubuntu 11.10. Furthermore, the brightness setting doesn't exist anymore in "Energy" options. It is now on "Screen" options and it doesn't seem to remember the setting after reboot.

So, how to make Unity remember brightness settings?

Solution 1

The short answer is: you can't. Gnome power manager doesn't save the brightness setting. The best you can do is to automatically set it to a reasonable default at startup.

For 11.10, the only solution I have found that works is the one given here: http://blog.ishans.info/2011/09/25/set-brightness-automatically-at-the-startup-in-linux/

Save http://ishans.info/attachments/article/65/setBrightness.py locally, change the brightness percentage in the last line to your preferred value, and add a new startup application to run:

python /wherever-you-saved-the-script/setBrightness.py

Solution 2

I haven't found a way to get Ubuntu (I'm currently using 13.04) to save the last used brightness settings, but the default brightness of 100% on my laptop was too bright, and forced me to find a workaround (using the link denrossalenga provided).

Just add a line like this to your /etc/rc.local file:

echo 60 > /sys/class/backlight/acpi_video0/brightness

This will give you a startup brightness of 60%. Change as appropriate.

Comments

[its_me]

Anyone coming here with the same problem, check out @dolhow's answer here. That's the one that works.

[Flimm]

Hi denrossalenga. Links are useful, but your answer would be much more useful if it actually included the relevant information. That way, we can read it easily, compare it, edit and improve it, and not worry if the linked website ever closes down.

[Peachy]

Welcome to Ask Ubuntu! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference.