Apple's macOS Sierra 10.12.4 has just entered its first public beta test, bringing the much-touted Night Shift mode borrowed from iOS.
Just a few days ago, Apple released macOS Sierra 10.12.3 and shortly after, it made the 10.12.4 beta available to developers. It's now taking the next step in the process.
Following the developer beta, macOS Sierra 10.12.4 is now up for public beta testing, not just for developers.
The latest macOS Sierra 10.12.4 public beta is available for download to anyone who is part of Apple's beta testing program. The new beta brings a number of new features and improvements, including support for Shanghainese dictation, cricket scores for Siri, and improvements for PDFKit.
Most notably, however, macOS Sierra 10.12.4 brings the iOS Night Shift mode to the Mac, aiming to help users sleep better by reducing the exposure to blue light on the screen. Blue light can affect the circadian rhythm of the body and affect one's sleep, but Night Shift pledges to reduce the negative effects.
macOS Sierra Night Shift Mode
Night Shift mode first made its debut on iOS 9.3 as a screen effect that gradually changes the display brightness from a blue tint to a warmer yellow tint as the day turns into night.
Blue light enables device screens to have high visibility even in bright light during the daytime, but at night it can have a negative impact on the body. In a nutshell, the human body is tricked into treating the blue light as sunlight, and in turn it produces less melatonin - the sleep hormone. Blue light also makes one more alert, which, combined with reduced melatonin production, can give way to a sleepless night.
The Night Shift feature simply lessens the amount of blue light to favor the body's natural responses to light, which is to start producing more melatonin to prepare the body for a restful night sleep.
On Macs, Night Shift will be accessible through the Display menu in System Preferences. Users will be able to set a time for the feature to activate, or choose to turn it on or off manually. Users will also be able to adjust the display's color temperature when Night Shift is on, choosing how warm they want it to be.
The Mac's Notification Center will also offer access to the Night Shift mode, sporting a toggle for the feature so that users can manually turn it on or off.
Beta Test Risks
As always, keep in mind that betas should not be installed on a primary device because they are not stable builds. Beta tests are designed to discover bugs and issues and are therefore unstable, often involving memory leaks, kernel issues or some other bugs. Beta testing programs always carry a risk, which is why it's highly recommended to install beta software only on devices reserved for testing purposes.
Those who would rather not take any chances with unstable builds might want to wait for the official public release to get the stable build. The public releases typically follow within weeks of the first beta release, so it shouldn't take too long for macOS Sierra 10.12.4 and its Night Shift to exit beta and reach the general public.
