Up until a few months ago, I could not stand using my laptop in the dark. To cope, I would turn the screen brightness down to the minimum, but even then, my eyes would be cringing after several minutes. Then I would pull out the sunglasses, but that made the screen look all weird.

What happened a couple months ago was that I found out about a wonderful utility called Flux (the developers of this project like to call it f.lux). On their website it said:

During the day, computer screens look good—they’re designed to look like the sun. But, at 9PM, 10PM, or 3AM, you probably shouldn’t be looking at the sun.

If this could clear my night time eye sores, I thought, then it’s worth a try. So I downloaded it, around 10PM that night.

What f.lux does

The first thing f.lux did to my computer screen? Turned it to a glowing orange, akin to reducing the color temperature of the screen. And indeed, that’s what f.lux was doing. A quick examination of f.lux’s settings revealed this:

F.lux will set your monitor’s color temperature, based on the time of day. You can change the temperature settings to your liking. For me, the night-time temperature setting is at 3400K, which gives the screen a very mellow glow. During the day, my color temperature remains at 6500K, the default setting for my laptop (some monitors are set at 9300K). Between these phases is an hour-long transition between color temperatures, so subtle that I don’t even notice.

To compute the daytime and nighttime for where you are, you manually give f.lux your location. F.lux then automatically gets the sunrise/sunset time at your location, every day. After setting your location, you can forget about maintaining f.lux, since it will do all the work for you.

Settings and features

As mentioned before, you can set your own preferences for screen temperature. I recommend setting the transition speed (item 3 in options) to 60m so that you don’t notice your screen all of a sudden becoming orange.

f.lux’s menu gives you many options, and they are very intuitive. One of the most novel that I’ve seen is the darkroom mode, which I presume would be very useful for people who work in, well, darkrooms.

Why you should get it

Other than avoiding computer usage at night, this is the best thing you can do for your eyes when at the computer. When I got it the first night, it didn’t seem like much. But after a week or so, I noticed that my eyes weren’t drying up like the Sahara Desert anymore. A month later, I turned off f.lux at 2 AM, and the blue light poured forth, scorching my eyes. I couldn’t have imagined how I worked without f.lux.

The research is there to support f.lux’s usage. In 2012, the American Medical Association (AMA) made the following statement:

“Exposure to excessive light at night, including extended use of various electronic media, can disrupt sleep or exacerbate sleep disorders, especially in children and adolescents. This effect can be minimized by using dim red lighting in the nighttime bedroom environment.”

More specifically, a study in 1988 found a new type of light sensor in the eye, called the “melanopsin retinal ganglion”. According to an article on the National Institute of Health’s website (NIH.gov):

These cells provide signals to the suprachiasmatic nucleus (SCN), the brain’s master clock. They project to many other brain regions as well, influencing myriad aspects of human physiology. Moreover, research would show, they are uniquely sensitive to blue light.

In short, exposure to the kind of blue light emitted from the screens of many digital devices today affect your body clock. This clock, among other things, regulates your sleep/wake cycle by controlling melatonin release. What f.lux does is it cools your screen’s temperature such that it emits longer wavelengths of light in the red/orange area of the spectrum. This sort of lighting prevents stimulation of the photoreceptors connected to the body’s master clock.

Try it out!

Seriously, your eyes will thank you. For the five or so months that I’ve been using f.lux, I’ve gotten better sleep at night, and my eyes no longer feel strained under harsh, blue light.

f.lux is very small, unobtrusive, and runs automatically at startup. Just set it up once, and forget about it.

Website: http://justgetflux.com

Available for Windows, Linux, Mac OS, and iOS.