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by karmakaze 2675 days ago
It's not the light that bothers me it's only the blue component. Dark mode does help a lot. All my ides/editors are dark mode (except xcode but I rarely do iOS) where I spent most of my time.
1 comments

There is a big difference between a monitor that is off and a monitor that on, but every pixel is set to black. The latter gives off enough light -- particularly blue light -- that I definitely would get worse sleep if it were near my head. (This applies to monitors with backlights -- OLED and probably plasma monitors are a different story.)

One way to reduce the amount of blue light coming into the eye, it seems to me, is to add red light, which causes the pupils to contract, which makes it so that less of the blue light outside the eye will enter the eye.

I get the impression that the light coming from a black pixel has a lot of blue in it, and that turning on the red sub-pixel would decrease the amount of blue light entering the eye because the pupil-contracting effect I just described (even though it would not decrease the amount of blue light outside the eye).

My point is that using f.lux to dial down the color temperature as low as it will go (1200 K on my Mac after bedtime, giving the screen a pronounced reddish-orange hue) will result in less blue light entering the eye than making most of the pixels black would result in.

(Turning on a red light bulb would have the same effect, but f.lux is easier.)

A better way to avoid blue light would be to switch to an OLED display or to have a backlight that can be switched to producing only red light, but among the no-purchase-cost options, if the only displays available are LCDs with standard white backlight, making the screen mostly red seems to work better than making the screen mostly black.

(Neither is particularly good however if the goal is to avoid the effects of blue light on the brain.)

I don't know which colors are most effective at causing the pupils to contract. I don't have any hard data. But I'm sensitive enough to the effects of blue light on my brain at night that I believe it worthwhile to post here my subjective impressions of the relative effectiveness of f.lux adjusted (via its preferences pane) as red as it will go and a mostly black screen, which I achieved by making most things white, including a solid-white desktop, then "inverting the colors" using the keyboard shortcut control-option-command-8.

(It is possible to have both of the "interventions" or "settings" described above in effect at the same time, so I will add that once f.lux is as red as it will go, "inverting the colors" does not produce any additional benefit as far as I can tell.)

Good explanations. Note that often backlit LCDs do have settings for R, G, B drive levels which can be adjusted similarly to what f.lux would do, but without the timed functions. I have used that in the past to switch between 'normal' and 'user' reduced blue modes.
Here's an idea. I remember using some flakey DVI cables where one of the colours would drop out. How about making an HDMI-HDMI adapter that doesn't transmit blue? Even better make it a splitter where one has blue and one doesn't and feed them both into inputs of the same display.