My GNOME 3.28.2 Is Missing Monitor Brightness Control

[michael-bielesky]

Dear All,

I recently installed Ubuntu 18.04 that came with GNOME 3.28.2 as the GUI. I have desktop PC with an AMD® Ryzen 5 2400g processor; graphics: AMD® Raven; 64-bit; 250 GB SSD. Weirdly there is no brightness control anywhere to be found neither in the Launcher nor in the Screen Display Settings. I'm currently controlling the brightness through the following command:

$ xrandr --output "my-monitor-name" --brightness "number_from_0_to_1"

From what I've seen there should be a slider control below the volume control in the Launcher. Ubuntu seems to be up to date and the Livepatch is ON. I would appreciate your help with this matter very much!

Sincerely,
Michael

[deadflowr]

External monitor?

[michael-bielesky]

Yes, an LG monitor connected via HDMI.

Mike

[deadflowr]

Yeah, external monitors rarely, if ever, get the brightness controls in System settings.
On non-laptops I've never seen them.
You might look at this
https://launchpad.net/~apandada1/+ar...ess-controller
Should still work.

[Autodave]

Your brightness control should be in the menu of the monitor.

[michael-bielesky]

Hi,

It's been so long since I'd worked on a desktop PC that I found it weird not to be able to control brightness through the operating system. Deadflowr, thanks for the link I'm going to look into this!

Mike

[Holger_Gehrke]

Another tool that might be helpful is ddccontrol and it's GUI gddccontrol. It uses DDC/CI (Display Data Channel/Command Interface), a protocol that gives access to most of the controls in the OSD-menu of a display. While xrandr and tools based on it change the image that gets send to the display to control brightness, color balance and the like, ddccontrol actually changes the settings of the display.

Holger

[michael-bielesky]

Thanks Holger_Gehrke, I'll also look into this.

Mike