What is “Night Shift”
The iOS 9.3 update for Apple’s mobile devices introduces a new feature called “Night Shift,” which is pretty interesting, but little information is available. In summary, this is a feature that helps you sleep more easily at night after switching your iOS mobile device, such as your mobile device. For example, if you have not used an iPhone, even if it is not limited to the iPhone, it emits blue from the device.
Many studies have shown that nighttime exposure to brilliant blue light can affect your circadian rhythms and make it difficult to fall asleep. Night Shift uses the clock and geo-localization of your iOS device to determine when the sun goes down in your position, and then automatically changes the colors of your screen to the hottest end of the spectrum. In the morning he returns the screen to its normal configuration. – Apple
I wanted to dig a little deeper, so I had a spectrometer and measured the light that normally comes out of the screen of an iPhone SE, as well as the night shift mode activated. I used a white image that appears on the screen with the iPhone configured to use the maximum available brightness level. Below you can see the results with my comments on what really changes and what does not change … it will be a bit more technical, although in the end I will try to give a simpler explanation.
How to Enable the Night Shift Mode
The Night Shift mode on supported devices can be enabled manually from the lower sliding menu of the iOS device (Control Center) or from Settings / Display and Brightness / Night Shift. There are two modes you can choose between: an automatic Sunset to Sunrise switching or manually defined On and Off hours that you can set such as 22:00 to 7:00 for example. There is also a slider that allows you to increase or reduce the level of “warmth” that you get with the slider set to the middle by default.
Here are Apple’s mobile devices with Night Shift support: iPad Air, iPad Air 2, iPad mini 2, iPad mini 3, iPad mini 4, iPad Pro, iPod Touch 6G, iPhone 5S, iPhone 6, iPhone 6 Plus, iPhone 6S, iPhone 6S Plus, iPhone SE.
Standard Visible Spectrum for White
Thus, the white light from the screen of the iPhone SE is scattered throughout the spectrum of visible light (white is a combination of the main colors red, green and blue). As you can see in the white color, there is much more blue light compared to green and red. It simply means that we generally get a color temperature closer to the colder side, so let’s take a closer look at some numbers.
Measured color temperature: 6841 Kelvin
Measured illuminance: 546 lux
Color rendering index measured (IRC): 86.5 Ra
Medium Night Shift Spectrum for White
This changes the color spectrum of the white iPhone screen when night mode is enabled by default (middle slider). What happens now is that the blue component of white stays at almost the previous level, but the green and red components have increased significantly. As a result, the overall appearance of the screen becomes warmer, but in fact we do not reduce the blue light itself, we simply erase its effect by increasing the other two components of the white color – green and red. Here are the key steps to show how the white light of the iPhone screen has changed with the default Night Shift Enabled configuration.
Measured color temperature: 4260 Kelvin
Measured illuminance: 394 lux
Measured Color Rendering Index (CRI): 90.3 Ra
As you can see, the color temperature has shifted strongly toward the hottest side of the light spectrum, and the overall intensity of the light has also decreased by a little more than 150 lux. Interestingly, the CRI index has shifted slightly to the presentation of a good source of natural light, so that the light emitted on the screen of the device in this state appears more natural than artificial.
It seems that at this moment we still do not reduce the blue light, but we mask it, although the end result is independent. In essence, what we’re getting is something akin to transitioning from natural light (with standard screen colors) to something that naturally occurs in Sundown. We get a warmer light that is less intense compared to cooler colors with a higher intensity of light in front of it. Well, that sort of natural feeling, though perhaps not enough, still works well enough to fool our body watches.
Maximum Night Shift Spectrum for White
Move the night-shift slider to the maximum available level and measure the visible spectrum of white light emitted by the iPhone SE screen. Finally, we can see that the blue component of the color is reduced a few times, the green returns to almost the average level (near the spectrum of the standard screen), while the red component stays high.
Measured color temperature: 2854 Kelvin
Measured illuminance: 286 lux
Color rendering index measured (IRC): 92.9 Ra
We went even further towards the light spectrum of light and we see a decrease in blue, which makes things too hot (at least for me). Bigger reduction of light intensity with over 100 lux more and even better CRI. Then this should be even more effective if the warmer color does not bother you. Personally, the average level is not so extreme and does not affect the accuracy of the colors too much, so it is perfectly usable; However, it is a bit too much, although it can work even better at night when you use your smartphone or tablet. before you go to sleep.
Could it Be Made Even Better
After a technical analysis with the measurement of the spectrum of visible light for the white color, which is displayed on the screen of the iPhone SE without the night mode, and thus I can suggest an even more optimal solution. This can be done as follows: starting with the standard average level for the sunset night shift mode and gradually increasing to the maximum level since it is late at night. In fact, it is quite easy to track the average user’s sleep time for a few days and to have a good estimate of when the maximum night shift should be reached. In this way, the user will not notice a quick and significant change in appearance, as things will gradually change in small steps, so that he will feel much more natural and will also lead you to “fall asleep”.
So the Night Shift Mode Does Work
Even at the standard mid-level, night shift mode can help people who like to use their smartphone or tablet when they go to bed before falling asleep. The decrease in the actual amount of blue light perceived by the person using the device causes the body to begin production of the hormone melatonin, which is primarily responsible for the preparation of our body for sleep. It is a known fact that our body has a stronger reaction to the blue light, which basically prevents them from starting to produce this hormone, although in fact every kind of light has this effect in the production of melatonin, which is blue simply the most powerful. This is precisely why some people take pills containing melatonin (sleeping pills), which allows them to sleep easier, but this may not be the best solution to the problem.
If you have trouble sleeping at night, if you go to bed using your Apple smartphone or tablet and have not yet tried Night Shift, I strongly recommend that you see if you can help. But keep in mind that it’s even better if you just do not use your smartphone or tablet in bed. Even if you do not use it, but still have trouble sleeping after bedtime, you should remember that there may be other factors that may additionally cause your sleep problem. Blue light comes from a mobile device. in bed. I’m talking about things like too much stress during the day, for example, it’s also one of the most common causes for people who have trouble sleeping properly. There are a few other causes of sleep problems, but since I wanted to explore Night Shift mode on Apple’s iOS devices a bit more, I do not want to talk too much about it now.