Redshift is a command line interface (CLI) program for adjusting the screen color temperature based on your surroundings. According to the developer, Redshift was inspired by the popular f.lux software. We can set the geo-location of our computer, the temperature range and the method of changing the screen temperature for it to work.
Two ways of supplying parameters
There are two ways of supplying the configuration data to Redshift. First method is through a command line. The second method is by creating a configuration file that contains all the data. While first method is quick and simple, the second method is best suited for repeated uses.
Finding latitude, longitude and color methods
Before you supply any data, you have to find out two things – your geo-location coordinates (latitudes and longitudes), and the color changing methods available. For the coordinates, you can visit Google Maps and click on the small hairline target icon in the lower-right corner. After this, right-click on your location on the map and you will see the coordinates.
For finding the available color changing methods, you can give the command redshift -m list. On a Windows PC, you are most likely going to find the method wingdi and dummy. On a Linux computer, there are many other methods available for your use.
Redshift in continuous update mode
Once you have all the data, you can give the command redshift -l Location -t Color -m Method. In this command, Location is latitude and longitude separated by a colon such as 10.3:123.8. The Color is maximum and minimum color separated by a colon such as 6500:3500. And the Method is your method that you found earlier. An example command would be redshift -l 10.26:123.84 -m wingdi -t 6500:3500 .
Redshift in one-shot mode
When you supply location and color range, Redshift keeps continually updating the color within the specified color range depending on the local time at your location. But you can also run Redshift in one shot mode. For exmaple, if you want to change screen color to 4500 and quit, then command would be redshift -o 4500.
Reverting changes made by Redshift
So once you change the screen color, how to revert back to the normal color and quit Redshift? For this, you can run the command redshift -x. This resets your screen color back to normal. But before this, you might have to kill all the running instances of Redshift which can be done using the command taskkill /f /im redshift.exe.
You can download Redshift from https://github.com/jonls/redshift.