If you choose the "Sunset to Sunrise" option, your computer will use your location to determine when to turn the feature on and off.
From that screen, you can also drag the slider to change the color of your screen during Night Shift. The "warmer" the screen is, the less blue light it gives off.
How to Turn Off Blue Light on a Mac With Night Shift
Night Shift is a feature on Mac computers that automatically shifts the colors of their display to the warmer end of the color spectrum after dark to help reduce the risk of blue light in the evening. It requires macOS Sierra 10.12.4 or later and one of the following Mac computers, using the built-in display or the displays listed. Users 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.
Use Night Shift on your Mac - Apple Support
Step 1: Click the Apple logo in the top-left corner and select System Preferences on the drop-down menu. Alternatively, click the System Preferences icon on the Dock .
Step 2: Select Displays in the pop-up window.
Step 3: Click the Night Shift tab in the following pop-up window.
How to Use a Blue Light Filter on Your PC or Mac | Digital Trends
Apple added a blue light filter for Mac OS in March 2017 called ‘Night Shift'. To activate the feature, go to System Preferences > Displays > Night Shift . You can choose to activate it between sunset and sunrise or specific hours, or enable it until the next day, or adjust your Mac’s screen color temperature
Blue Light Filters for iPhone, Mac, iPad, Android & Windows - MOONA
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