Use Night Shift on your Mac
Night Shift automatically shifts the colors of your display to the warmer end of the color spectrum after dark.
Studies have shown that exposure to bright blue light in the evening can affect your circadian rhythms and make it harder to fall asleep. Night Shift uses your computer's clock and geolocation to determine when it's sunset in your location. It then automatically shifts the colors in your display to the warmer end of the spectrum. In the morning it returns the display to its regular settings.
How to set up Night Shift
Make sure that your Mac meets the system requirements for Night Shift, then follow these steps:
Choose Apple menu > System Settings (or System Preferences).
Click Night Shift.
From here you can create a custom Night Shift schedule, schedule Night Shift to turn on automatically from sunset to sunrise, or manually turn Night Shift off or on until sunrise or the scheduled time. You can also make the color temperature more or less warm when Night Shift is on. Warmer color temperatures show more yellow and less blue.
System requirements for Night Shift
Night Shift requires macOS Sierra 10.12.4 or later and one of these Mac computers, using the built-in display or the displays listed:
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