Anyone use blue-light blockers or reducers?

Continuing the discussion from What monitor(s) do you have for programming? - just wondering if anyone has used blue light blockers or glasses?

Ben Greenfield mentioned them in a youtube podcast recently and iirc, said blue-light blocking glasses can help prevent damage as blue light can actually damage eye health - not just keep you awake as what we commonly associate it with. (Think it might have been in this interview.)

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Definitely not. I feel the effect is much less pronounced when you have a lot of natural light in the room and never entertained the idea. I do have a quite conservative schedule for my OS-es to auto turn on night mode (= reduce blue) though.


KDE and Android both have had built-in (or addon programs further in the past) to reduce/remove blue/green light from the monitor for many many years that I’ve used, it’s much easier on my eyes, but my eyes are pretty sensitive. ^.^

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I use a D50 colour profile on my Mac (commonly used for print and where the white point is warmer) sometimes with the night-mode, however there’s only so much software can do:

However, these software tools are simply incapable of blocking all the blue light emitted by the screens of your gadgets. There’s still the LED backlight emitting blue light as part of its white light, which these apps can’t do anything about. So if you are particularly sensitive to blue light and these apps aren’t doing enough, you could purchase a heavy duty physical filter to suit your needs.

This is also why I prefer to read on my Kindle, blue light is completely eradicated and you also don’t have any flicker or retina-burning brightness :smiley:

Software/night modes are definitely better than not having anything at all tho.

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Installed redshift-gtk last night since I moved from the awful GNOME 3 interface of Ubuntu to Unity which doesn’t have a blue light reducer. Redshift is working quite okay.


Here’s Ben Greenfield’s article about it - and a few quotes…

But the effects of light go far beyond its potential for positively hacking sleep or enhancing recovery, especially when it comes to the potential for artificial light to damage your overall wellness. The negative health impact of artificial light sources on endocrine and cellular levels in humans includes the risk of cataracts, blindness, age-related macular degeneration, mitochondrial dysfunction, metabolic disorders, disrupted circadian biology and sleep, cancer, heart disease and more.

For example, multiple recent studies have reported that exposure to artificial light can cause negative health effects, such as breast cancer, circadian phase disruption and sleep disorders. One 2015 study reviewed 85 scientific articles and showed that outdoor artificial lights (e.g. street lamps, outdoor porch lights, etc.) are a risk factor for breast cancer and that indoor artificial light intensity elevated this risk. This same study also showed that exposure to artificial bright light during nighttime suppresses melatonin secretion and increases sleep onset latency and increases alertness and that the circadian misalignment caused by artificial light exposure can have significant negative effects on psychological, cardiovascular and metabolic functions.

But LED’s can also cause severe retinal damage to the photoreceptors in your eye and have even been shown to induce necrosis (cell death!) in eye tissue. The American Medical Association even put out an official statement warning of the health and safety issues associated with white LED street lamps. Things get even worse once dimming and color changing features are introduced into LED lighting, which is a common lighting feature in modern “smart homes”. The reason for this is that LED lamps are a form of digital lighting (in contrast, the incandescent light bulbs and halogens light bulbs you’ll learn about momentarily are analog thermal light sources). In a color changing system that allows you to adjust the dim or color of the lights, there are typically three different LED sources: red, green and blue. The intensity of these three sources has to be changed to achieve different colors, and this feature must be controlled digitally via a mechanism called pulse-width modulation.

I rarely put the brightness on my monitor about 50%, but have seen some people with theirs set to 100% - that’s insane given how bright monitors are these days…

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Displays are not so bright when the sun shines directly into most of your room. :smiley: Especially the smartphone displays’ brightness values mean absolutely nothing if you have to pull out your phone while walking on a sunny street.

As for the studies, I’d take them with a huge bag of salt. Especially breast cancer closely correlated with artificial outside lighting? Very oddly specific and I’d bet they got to this conclusion since they didn’t have big sample sizes to work with.

Still, I am on their side – I am very sure artificial lighting is damaging for us. But I also believe there are ways to severely mitigate the effects, f.ex. I know people who prefer red light during most of their evenings and have reported feeling more relaxed and in a better mood in their free time at home.