Using redshift without geoclue: why doesn't it allow me to specify how I'd like to have my screen color temp changed / set my position manually?

Question

I'd like to use the redshift to change the screen color temperature before I intend to go to sleep.

Now it looks like redshift requires me to install geoclue. But I don't want to have that package installed. And in addition I'd like to specify the times for my screen color to be changed manually. Either by setting my position manually or by simply specifying the time it should start and end dimming.

Is there a way to change my screen color temperature like that with some other tool or with some trick maybe? I'm also interested in why that isn't possible with redshift even though it shouldn't matter whether it gets the data from geoclue position data or by some data entered manually.

I'm using Debian 9 with KDE.

Answer 1

You can totally make most of those things with redshift, and you don't really need geoclue installed. To set colors straight from command line just put:

redshift -l 55.7:12.6 -t 5700:3600 -g 0.8 -m randr -v

The -l option tells redshift about your location (latitude and longitude). You can also use a config file. For example:

     [redshift]
     temp-day=5700
     temp-night=3600
     gamma=0.8
     adjustment-method=randr
     location-provider=manual

     [manual]
     lat=55.7
     lon=12.6

If you save this as redshift.conf in your $HOME/.config, redshift will read these setiings whenever started. BTW you can start redshift on startup by putting redshift & in your .xinitrc file. All the examples above are taken from man redshift, lots of information can also be found on the redshift website.

Answer 2

Solved this via:
sudo apt-mark hold geoclue-2.0

sudo apt-get install redshift
sudo apt-get remove geoclue-2.0

and setting the location manually via the Redshift widget (KDE) by rightclicking the lightbulb icon -> Redshift Control Settings -> Advanced -> Location.

After removing geoclue Redshift itself fails to launch and says:

Failed to run Redshift
Trying location provider 'geoclue2'...
Unable to connect to GeoClue.
Unable to get location from provider.