F.lux

Protect your eyes and eyesight by using F.lux, a program for Mac that adjusts the color of your screen according to the time of day.

F.lux collects information about the surrounding light according to your city and country, so to use it, you have to let it know your location.

To get even better results, you can indicate the type of lighting in the room where you're working: halogen, tungsten, fluorescent, or natural.

F.lux tells you how much time you have before sunset, as well as the light intensity where you are.