27

Today I realized that Night Light stopped working in my machine. When I try to set it up, nothing happens. See attached gif:

trying to enable night light

I am not sure what's causing it to fail. I don't know if there are any logs generated by this tool, or if there's another way to enable Night Light.

Any idea what to try? This was working a few months ago.

When I check /var/log/syslog, there are some messages related to night light when I use the «Sunset to Sunrise» schedule, but nothing indicates that it failed:

Sep 19 22:46:37 sambayon gnome-control-c[22940]: no sunset data, using 16.00
Sep 19 22:46:37 sambayon gnome-control-c[22940]: no sunrise data, using 8.00
Marco
  • 523

6 Answers6

9

I encountered the same problem in 20.04, so I tried to reinstall gnome-control-center and then tried to restart my computer and it works.

Try running this command in a terminal to reinstall control center:

sudo apt-get install --reinstall gnome-control-center

and then restart you computer.

Greenonline
  • 2,182
Samkit Jain
  • 101
8

For me, It worked by just rebooting my system.

VARUN JAIN
  • 81
6

For NVIDIA GPU users: I had to reinstall my NVIDIA drivers after a kernel update. You can check if your driver is working with nvidia-smi -- if not, you may need to install drivers.

Łukasz Kidziński
  • 351
0

I encountered the same issue in Ubuntu 20.10. After turning on night light, I restart the computer and it works normally.

Nguyễn Đức Anh
  • 31
0

Flux was conflicting with the night light program, enabling the Manual mode worked for me.

enter image description here

sotmot
  • 105
Manoov
  • 1
0

Try disabling MST in your Monitor's OSD if it has that option.

Multi Stream Transport allows daisy-chaining multiple monitors via display port. I have a multiple-monitor setup and recognized that on the one monitor that has this option night light wasn't working at all.

Hyperplane
  • 311