> Dissatisfaction with the red lighting system caused the crews of many ships to alter the lighting within their work environment. Some would extinguish all lighting, and some tried a white light configuration in which the overhead lights in the vicinity of the visual display equipment were turned off, while lights away from the visual display equipment remained on. There were many complaints of eye strain, fatigue, and headaches. In addition, watch-standers reported that working under red ambient illumination was also fatiguing, made focusing difficult, and significantly impaired their ability to identify color-coded information from charts.
The notable thing about your links is the complete lack of the world. You don't need to preserve night vision stuck in a sealed metal box without windows.
The article doesn't seem to have a specific context. It talks about being in the car driving, but also about being in bed trying to go to sleep.
I'm not saying that you should have blue lighting in your bedroom, we know it's bad. The author did little research before writing this, and invoked authority (the military) without being aware that you can invoke the same authority to promote blue lighting.
Oh I agree with you about the article. Even with cars she shows an example from BMW that rather spoils his point - that's BMW since they adopted lighting as decoration like everyone else, white with some red highlights. My old BM 5 series was a very orange place rather more like the aircraft cockpit illustrated.
In fact all my old cars were - because the first thing I'd do on buying was turn the brightness for instruments right down. With incandescent bulbs that meant they became orange. My current car reduces brightness but keeps colour that I really wish I could do something about.
That's a ceteris paribus line of reasoning, though.
If we assume, for the sake of argument, that red light inhibits alertness while blue light promotes it, then that might change the calculus to, "maximizing night vision preservation isn't as important as making sure that we don't end up needing it in the first place."
Presumably the people stationed in that part of the ship don't often get up to fight. Some may be at weapon stations in that control room, so they fight best right there. Other crew would be fighting with small arms if necessary.
This dissatisfaction with red lighting makes sense. When Flux turns my monitor reddish-yellow, I get sleepy. When I'm in a darkroom, I get sleepy. I wouldn't want to be sleepy in the operations room of a warship.
There is one area I'd like to see a universal ban on blue spectrum LED's - street and commercial overhead lights.
I live in Salt Lake City and there has been an unfortunate push by Rocky Mountain Power to replace all the streetlights with bright blue/white LED overhead lights. Their output is significantly greater than the lights they are replacing and the light is completely obtrusive. In the city there is the unfortunate and unavoidable issue of spillage into peoples bedrooms.
I've also had the unpleasant task of coaxing my dog to give up the dead birds that have suddenly started showing up my back yard. Likely attributable to the new "better" lights.
I think this is a big problem in lots of cities. LEDs have clear advantages in energy efficiency and reduced maintenance costs and their use should be encouraged. But municipalities seem to be seduced by ultra-bright, blue-white LEDs because of the perceived "modern" look and because of the perception that it improves security.
While we'll never be going back to the orange glow of high-pressure sodium street lights, perhaps a compromise can be found. How about specifying 'halogen-match' (~2700K) colour temperature LEDs for street lights? White enough to create a secure environment, but warm enough not to quite resemble daylight and all the sleep-disturbing, wildlife-disrupting problems that come with that.
Another issue is the way that LED street lights are designed causes a huge amount of glare. Often as a pedestrian or driver, your line of site is directly into the LED matrix itself. With old-style street lights, reflectors or diffusers were typically used to reduce glare, but those have been done away with.
I believe that the highest lumens-per-Watt LEDs are higher color-temp, sadly, so I would think that the streetlights were optimized mainly for sheer output, and the cold, daylight temp was just a side effect. I doubt there will be a lot of enthusiasm for pulling down new, long-lasting LEDs, but possibly colored lenses could be retrofit to them...
I have fond memory of using amber monochrome CRT terminals/monitors, and I've preferred to it over the green or black/white monitors back in the days when color monitors were rarity. Amber/orangeish text always felt more soothing and pleasant, but on the other hand, green texts felt more readable (ie texts were easier to comprehend), although I couldn't explain why.
Edit: Back in the late 70's and early 80's, monochrome monitors were prevalent and one had to choose the screen color when choosing terminal/monitor. Apple 2's and most IBM PC's monitor were green, while Radio Shack TRS80 were bluish/white if I recall. At university, we had Wyse terminals with yellowish/amber color.
I also remember working on a terminal attached to a mainframe running IBM RPG III, and it was distinctly dark red, which was probably the coolest color I'd ever seen, and which I'd never seen anywhere else. That reddish color made me feel like I was in a sci-fi movie.
> Amber/orangeish text always felt more soothing and pleasant, but on the other hand, green texts felt more readable (ie texts were easier to comprehend), although I couldn't explain why.
The human eye has "better resolution" for green light (vs red and blue). It's also why the Bayer pattern array has twice the ammount of green elements vs red (or blue).
Not just resolution, but overall sensitivity as well - meaning that green light of the same intensity looks brighter. This is also why most night vision devices use green phosphor, why some flashlights have a green LED (less energy for the same perceived brightness -> more battery life), and why green lasers for pointing/marking are increasingly common.
Since black is the same black in both cases, a green CRT will therefore has a higher perceived contrast.
You can spend your bandwidth on colors or you can spend it on pixels.
(I recall having a 1600×1200 mono display at work circa 1990 when a high-end PC was pushing 800×600 SVGA. Beautiful and crisp, but porn^H^H^H^H the internet killed monochrome monitors.)
Is it really true though that a few tiny blue leds would affect our bodies that much?
If I recall correctly, significant effects required rather bright lights. The light level outdoors is like 100000 times brighter. A laptop probably won't make much of a difference then.
I run f.lux or redshift, but I'm suspecting that it really doesn't do anything rather than reminding me by going totally red and inconvenient that it's about time to stop trying to read or watch every interesting thing on the Internet.
For me, it's the endless source of interesting things that keeps me awake, I guess because I've stressed out and turned into a total information junkie. My mind craves information. Unfortunately it thinks that recordings of air traffic controllers etc is more valuable than sleep.
I always found color shifting annoying. Color is pretty important to me and I'd rather not see things through a dim tint. I always felt like most of the color adjustment tools were really gimmicky.
These days you don't even necessarily need a separate app like F.Lux or Redshift; Windows and Android have similar color-shifting features built-in to the OS. (Not sure about Mac or iOS.)
There are also other night mode apps that offer other tones. I've been using Blue Light Filter on Android lately and appreciate the level of controls it offers (color temperature, intensity, and screen dim)
It's not a matter of choice of colour, the way f.lux removes the blue is different than just adding an overlay (like Twilight and such do), that's why it needs root.
iOS does but is very subtle about the change. f.lux default settings are quite dramatic and turn the screen very red. Something in between seems right to me.
One day the weather app will get the outside colour temperature locally and match the OS to it. :)
Does anyone know of any way you can keep Night Shift on at all times on iOS or MacOS? It seems when I turn on Night Shift, it automatically turns off next morning when it's daylight time.
I think the same things applies to f.lux on MacOS. I would like for it to be at 1200K at all times but I guess that's not doable and it grinds my ears a bit because you can't do so.
Just speculating, but it could be that the levels don't matter as much since your pupils adjust to let in about the same amount of light regardless of the actual brightness.
Also, just an anecdote. But if flux is on I will get tired around 10pm. If it's off I won't get tired until well after midnight.
I personally think the "circadian" effects are overstated, but I remember being in a dimly lit sushi restaurant a couple years ago, and the cash register had a single blue LED on it. It was so bright that it illuminated the waiter, a piercing blue/white that was completely out of place in the room.
Bright LEDs have no place anywhere where lights are dim, especially on electronics. Someone found this problem irritating enough that they started selling stickers specifically for the use of covering the damn things. https://www.amazon.com/LightDims-Black-Out-Electronics-Appli...
I highly recommend using f.lux to adapt screen colors at night. It makes reading some pages harder once it goes into full candle-light mode, but I take that as a signal that I need to start getting ready for bed!
Redshift is one of the first things I install on Linux, and I set it pretty orange in the daytime too. It works on X and Sway; I'm not switching to Wayland until I can use it. (GNOME also has a built-in blue light filter with a manual time option [thanks to comment below]. I know KDE is working on a similar feature for Wayland but I don't know how it works.)
Redshift runs very well atop my KDE and my sleep would surely suffer without it.
Be sure to fiddle with the config [0] to customize the color temperature of the application even further to your liking -- the default settings can sometimes mess with your display's viewing angels.
Gnome built-in blue light filter has two modes : "Sunset to Sunrise" or Manual where you define your own schedule. Should work on Wayland too but I did not test it as I stay on X for now.
I've been using it for a long time but I have a question.
Sometime ago somebody on reddit or here on HN claimed in a comment that f.lux does not actually reduce the amount of blue light if you measure it. Unfortunately I never saw any replies or sources, and looking for discussions about that subject were unsuccessful.
Does anybody have any actual knowledge that could support or refute that claim?
PS: I hate it when people make claims like that and don't even attempt to support it. Now I'm still looking for an answer months later.
I find it hard to imagine how the screen could look yellowish while still outputting a lot of blue, but you can actually check it - look at the blue sub-pixels with a magnifying glass or your phone camera and see if they actually dim.
Could it be that on lcd screens you can't eliminate blue light fully? Tested this with comour filters on iphone 8. Fully red, still emits blue at angles when held to a wall. Apple watch with red flashlight on doesn't do this. (It's oled)
I think it was in f.lux's blog that while f.lux does reduce amount of blue light, apple's built-in night mode (the one on your iphone for example) didn't.
Contains a link where a graph (which I don't understand) is almost identical with and without sleep shield.
lorna F.LUX TEAM Aug 17, 2017, 5:48 AM
And here is the same iPad with one of the many filters that claim to help sleep (unless they are a deep orange, most of them do absolutely nothing): https://fluxometer.com/rainbow/#!id=iPad%20Pro/6500K-iPad%20Pro&filter=filter/SleepShield
But that SleepShiled looks like is a physical device actually.
I prefer it since you can control it better. It can also remove more of the blue light. I actually have it remove a little bit of blue light all day long and then really remove a ton of it at night.
Blue LED inventor and Nobel Physics Laureate Shuji Nakamura was my former classmate at UF MSE back in the late 1990s. At the time a pioneering institution in MOCVD of wide-bandgap GaN. Even back then there was a sense this would be a world-changing materials discovery.
And we may be on the cusp of the next brilliant revolution in lighting displays with solid-state Graphene. The graphene / graphene-oxide boundary represents a near infinite bandgap differential. And with a controlled applied voltage, can be tuned to any color in the visible spectrum and beyond.
Combined with extensive end user testing in the Human Psychology Lab this could very well lead to a breakthrough.
In my own experience the most glaring is the 5am wake up time. When pupils are dilated. And you are checking any overnight messages from Asia or Europe. Occasionally Nite Mode will simply fail to register and you get a good blast of photons directly on a still sleepy and sensitive retinal plane. Long term repeated exposures can't be a good thing.
I have a hatred of blue LEDs on household equipment, they always seem to be significantly brighter than their red/green/orange counterparts.
For example: If I need to leave my computer running overnight running a job, I have to tape over or block the power button in order to get a decent night's sleep as it has a nasty habit of utterly illuminating the room - the hard disk activity light is much more tolerable.
The terrible thing about blue leds is that, even though our daytime vision is by far the least sensitive to blue light, our low-light vision is the complete opposite!
One time I stopped in at a strip club in Connecticut. I only stayed for about a minute because all the lighting was blue. It was really unpleasant in general, and, worse, I couldn't really see anything I would want to see. And if I could see anything, I'm not really into the White Walker look.
Blue lights are often installed in places where people do intravenous drugs and the owner of the place wants to discourage them from doing that. Blue light makes it hard to see a vein, so hard drug users have to go somewhere else to shoot up.
I've always thought, wouldn't the light from your cellphone override this measure? Not even the flashlight, just turning the screen on would probably help...
Here's a long personal (boring) story of my experience with different light colors.
Back when CFL bulbs were becoming a thing, I discovered with joy how much less irritated my eyes were (and how much more relaxed my mind was) when I used CFLs with high color temps - "daylight" temps around 6300K compared to the piss yellow color of typical incandescent bulbs. At first the "blue" light was shocking, but after a moment of adjustment it became so pleasing and illuminating.
So I fully embraced that for years, gleefully moving to LEDs with similar color temps. My last office had my custom made shelf all the way around the room that had upward firing LED strips. It was awesome!
But then, after an unfortunate several months of insane crunch-time work, I started having eye problems... many different weird things happening with my eyes, from focus issues to strange pressure feelings.
I did an about face and shifted my monitors to more red, at much lower brightness, and with dark mode UIs where possible. Then I turned off the super awesome daylight LED strips and just used one yellower little LED lamp behind my monitor to provide a bit of desk surface light. Almost instantly my eye issues went away. I was still working far too many hours each day, staring at my screens. The only change was brightness and color of all my light sources.
My ability to sleep didn't seem to change, but my mind was always too busy to fall asleep anyway. So I can't claim that changing colors improved my sleep. It did, however, seem to stop harming my eyes.
I just want to say that the links to cancer, obesity and even some of the sleep problems are probably concluded from correlation, not experiments (since you can't say: hey you, please only use orange screens for the next 30 years and then we scan you for cancer X).
And I think this is a problem, since you can't now for sure that wether the cause is blue light or the lifestyle people who are exposed to a lot of blue light have (staying up late, long office jobs, who knows?).
To be clear, I do not refute the harm of blue light, I just want to suggest being cautious with the broader health effect claims.
It is amazing to me that colors of instrument readouts is not regulated, when the research is extremely clear that red and orange (and yellow) are much better for night vision than white, blue and green. Add to that the huge screens in most cars these days and you have a recipe for night blindness caused by just looking at your infotainment screen for a second and not seeing a pedestrian due to the ghost image left on your retina.
I get the same thing in my city with digital billboards. I can't believe it's legal for them to show pure white backgrounds at night, especially flipping from a mostly dark background. Driving down the road when suddenly a massive billboard floods your eyes with bright-as-day pure white light... not a good thing.
That one is usually regulated at the city level. You might talk to your city council. There are many, many good reasons to disallow that kind of lighting, it could be it just hasn't been on your city's radar yet.
Do you have any link to the research you're reffering to ? I looked into this a while ago when wondering why my headlamp had red ligths, and people seemed to advocate for a dim green light (eg. http://stlplaces.com/night_vision_red_myth/), but I'm struggling to find any research article backing this
And the brighter headlights on other cars likely cause your pupils to narrow, allowing less light into your eyes, so you feel like you need brighter headlights.
Until the 90's the standard color for headlights in France was yellow, not white. That was so much easier on the eyes when driving at night (and also safer in foggy conditions).
Yes! I really miss my 900's night mode button which would disable everything but the speedometer. I would call that "stealth mode" even though towards the end of its life it was one of the loudest cars on the road due to a bad muffler.
There was some real forethought in the design and layout of the cars in general but the dashboard display is perfect. I wonder if it's true when people say they took elements from the jet aircraft they made.
It would be useful to know what percent of the population is affected by this. I look at my computer/phone up until I go to bed, and I’ve not seen any adverse effects. It’s an N or 1, but surely I’m not the only person who doesn’t experience the negative effects this article warns about.
Blue LEDs are a relatively recent thing, we’ve had decades of green and red LEDs on our gadgets and I’d expect the trend to balance out over time. RGB seems to be going through it’s thing and at least if you’ve got an RGB keyboard you can dial in whatever hue you like.
I find it sort of funny that the article describes all screens (and even lighting) as touchscreens in the title. I guess that is a sign of their ubiquity.
Blue started as a difficult color to make (and it still wears OLED screens much faster) and became a symbol of modernity. It also creates an interesting halo effect in most lenses (even our eyes) because we can't focus it well.
I've used Apple's Nightshift feature since it launched, and although I'm not sure about any changes to sleep patterns or general health affects, it does help reduce my eye strain at night. It's also interesting to see how quickly I become used to the colour shift, and how artificial the interface looks if I turn Nightshift off during the night.
i agree for leds, car displays and things like that, but for people who use their devices to looks at mostly calibrated pictures (photography/graphism/art/etc.) the warming displays functionality at night is not an option...
How about not doing color-sensitive work at night? "Night". Even only looking at biological systems, the body shifts to a very different regime during that time. Different hormones and all that, doing repairs and house cleaning. Humans don't come from a nocturnal line of animals.
http://warbird-photos.com/special/temp/CVN72-D5_Combat_Direc...
https://www.extremetech.com/wp-content/uploads/2015/12/Zumwa...
https://static01.nyt.com/images/2016/03/31/blogs/20160331WIP...
https://upload.wikimedia.org/wikipedia/commons/d/d1/US_Navy_...
Quotes from a military study regarding lighting:
> Dissatisfaction with the red lighting system caused the crews of many ships to alter the lighting within their work environment. Some would extinguish all lighting, and some tried a white light configuration in which the overhead lights in the vicinity of the visual display equipment were turned off, while lights away from the visual display equipment remained on. There were many complaints of eye strain, fatigue, and headaches. In addition, watch-standers reported that working under red ambient illumination was also fatiguing, made focusing difficult, and significantly impaired their ability to identify color-coded information from charts.
http://www.dtic.mil/dtic/tr/fulltext/u2/a273682.pdf