We're on our computer probably way longer everyday than we should admit, and have been known to welcome both dawn and dusk in a single sitting in front of our computer. But lighting in the daytime is much different than the lighting at night, especially in home offices with windows. F.lux is an application which adjusts your monitor's color temperature throughout the day, warm at night and brighter during the day, hopefully relieving eye strain.
Setup is as simple as using an auto-location detection feature or plugging in your zip code, then choosing what sort of interior lighting you use. F.lux takes it from there, automatically adjusting the screen in either a quick 20 second mode or gradually at an hour's pace. Here's a quick before and after video we captured on our own setup:
F.lux is available free for Mac, Linux, Windows XP and Vista users at stereopsis.com.
[via BNeato]
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Ansela: the app doesn't actually turn down the brightness, but instead changes the temperature setting, so your monitor is just as bright, but has a warmer display. Personally, it can end up a little too warm (orange/yellow) on my Dell, but it does make a noticeable difference once you see the before and after personally.
It's a free download, so there's not really any risk except for a loss of time.