How to change temperature of the screen and set my position manually with redshift?

I'd like to use the redshift to change the screen color temperature. 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.