10 ms·
LED lighting undermines visual performance unless supplemented by wider spectra
- userbinator 10mo agoVery interesting. I've always thought that there was something a bit "off" about LED torches and car headlamps; the brightness is there, but something about the light just doesn't seem to illuminate as well as an old dim incandescent or even fluorescent tube.
- deleted 10mo ago[deleted]
- rpcope1 10mo agoI get that they're more efficient in some sense, but man the LED streetlights and other big lamps are so irritating and make things like like such ass compared to mercury vapor or even sodium lights.
- VagabundoP 10mo agoEven a colour filter would help with the harshness.
- adrian_b 10mo agoTrue, but that lowers the energy efficiency. For LED lamps, the color must be controlled at the emission source, not by filtering, i.e. by using an adequate combination of different conversion phosphors, to ensure a neutral white with a quasi-continuous spectrum, instead of a bluish white with great narrow peaks in its spectrum. Unfortunately, the phosphors for the latter variant are much cheaper than for the former, so the lamp vendors have the incentive to make the lamps as bad as possible.
- yial 10mo agoBy must, is that only for energy efficiency? I ask only because I was retrofitting some navigation lights on a sailboat - and you can’t just upgrade the original incandescent bulbs with LEDs (or aren’t supposed to). You are either supposed to get a special LED (backing up what you’re saying) or there are some new red/green enclosures that are differently treated / tinted to then put a “white” led into. But I am so far from an expert on that, I may be completely misunderstanding.
- adrian_b 10mo agoWhen you use any kind of filter for a lamp, that stops a part of the light produced by the lamp, the part that has an undesired color. So, at the same electric power consumption you have less light, or you can compensate by using a more powerful lamp, to get the same amount of light even with a filter. In both cases the energy efficiency becomes worse, i.e. the expenses for electric power are greater per output light. On the other hand, when the manufacturer of the lamp controls inside the lamp the conversion of the light produced by the LED through fluorescence into the light that exits the lamp, there are chances to obtain a desired color and a certain shape of the emission spectrum by wasting less light than with external filters. Filtering can correct a lamp color that is not the color that you want, but it cannot fill gaps in the emission spectrum of the lamp. Cheap white LED lamps not only may have a too bluish color (or in some cases a too yellowish color), but their emission spectra may have gaps, so if a natural object from the environment happens to have a color that falls in a gap of the LED lamp spectrum, it will appear much darker than in daylight. This can cause orientation problems or difficulties in identifying certain things. Where LEDs are used for signalling, not for lighting, so pure colors are desirable, much less problems exist, so e.g. the replacement in the red or yellow signal lights of cars, of the old incandescent lamps with color filters, with monochromatic LEDs without color filters, has posed no difficulties.
- deleted 10mo ago[deleted]
- skandinaff 10mo agoTrue. Yet, somehow more and more cities install them blindly because efficiency. I remember when I moved to Odense Denmark in 2013 - they had LED street lights all over the place. I thought - this is the future compared to my uderdeveloped post soviet Latvia. And yet, I remeber when I moved back, streets at night looked so yellow because the city still relied on sodium lights. And my eyes felt much more comfortable. At the time I wrote it off to nostalgia or something, and here we are.
- orbital-decay 10mo agoThey're saying that the visual performance is indirectly affected by invisible wavelengths somehow. Not that you can see the difference between two types.
- siffin 10mo agoThey are saying that, and most real world LED lighting uses very cheap diodes, like, 99.9999% of them, which create very poor colour compared with incandescent bulbs, which create perfect colour representation. It's a big thing and you can buy LEDs which produce a better colour range, but they're much more expensive and not as energy efficient, because creating bold reds costs hard energy that no diode trick will ever get around that.
- orbital-decay 10mo ago>They are saying that, and most real world LED lighting uses very cheap diodes, like, 99.9999% of them, which create very poor colour compared with incandescent bulbs, which create perfect colour representation. Have you actually read the study? It's about infrared and has nothing to do with color rendering and visible spectrum. They're vaguely speculating about some mitochondrial mechanism of action not related to vision at all.
- AlanYx 10mo agoThat's the interesting thing about this study. A lot of people here are speculating around explanations connected to metamerism, but the control (Figs 7 and 9) partly rules that out.
- schiffern 10mo agoIt's a poorly controlled experiment. https://news.ycombinator.com/item?id=46764382 https://news.ycombinator.com/item?id=46764382
- nicoburns 10mo agoIt's usually the Color Rendering Index (the spectrum of frequencies that the light puts out). Incandescent bulbs more of less mimic that of the Sun, they are "black body radiators". Cheap LEDs tend to be missing a lot of the red spectrum. However, you can get LEDs that do this well. Look for one with a "CRI" of 95% or higher.
- kuschku 10mo agoThere's a massive difference between the 2600K of regular incandescent bulbs, and the 6000K of sunlight. That's why hollywood used HMIs until they migrated to LED.
- nicoburns 10mo agoThere is, but most humans are used to the spectral pattern of black body radiators at all color temperatures. Be that sunlight at higher temperatues or fires / candlelight at lower temperatures.
- kuschku 10mo agoRegular exposure to fire/candlelight has only existed for a hundredthousand years, while mitochondria have existed almost unchanged for millions of years. So even that assumption would require further study.
- scythe 10mo agoFor professional applications there are sulfur plasma lamps which have a continuous spectrum at high efficiency. Unfortunately they aren't economical below about 1000 watts which is impractical for many applications. The technology basically works by continuously microwaving (think oven) a small amount of sulfur gas. The development of solid-state microwave emitters — most microwave generation is still done with vacuum tubes — might help miniaturize the devices. However, it's hard to beat the simplicity of an LED.
- zahirbmirza 10mo ago
- Saris 10mo agoYes lots of them use cheap LEDs with poor CRI, high color temperature, and a huge blue spike in the spectrum. All of that leads to a very bright looking light that also doesn't let you see detail very well.
- mjmas 10mo agoSomeone please tell the Australian government now that we've essentially banned other forms of lighting. (except fluorescent)
- novok 10mo agoYou can't buy heat lamps? They are even more infrared and last longer. Also LED lighting can have infrared, have a significantly more smoother spectrum curve and still last +20k hours without burnout. The cheaper bulb spectra that they show is a blue led + phosphor coating, but there are infrared LEDs, UV leds, and more. You can make quite the convincing sun simulation, even better than any incandescent bulb, but there is almost no demand for UV + Infrared super full spectrum lighting unfortunately. Only movie & theater lights come close.
- krackers 10mo ago>LED lighting can have infrared, have a significantly more smoother spectrum curve and still last +20k hours without burnout Do you have a link to a bulb that you can purchase meeting all these criteria? The only one I'm aware of was this obscure "StarLike" that was never actually sold in bulk. LEDs can be made good in theory sure, but in practice they are all terrible in light quality compared to a standard incandescent. https://budgetlightforum.com/t/sunlike-vs-starlike/64155/7 https://budgetlightforum.com/t/sunlike-vs-starlike/64155/7
- novok 10mo agoYou would need to see the spectra of the various LEDs available and create a mix along with phosphor mixes. The closest thing is something like a BLAIR-CG light engine from aputure where they have something like 9 different colors of LEDs that mix together, but they don't put any infrared leds in them because they are for movies and they don't put any UVB or proper UVA leds. But there are infrared, UVA & UVB LEDs that you could apply the same kind of engineering principle to make something that closely follows the sun spectra. No, you can't buy them as bulbs. The closest thing is those red light therapy panels that include them.
- noosphr 10mo agoI have incandescent light bulbs at home I have to pretty much smuggle from China. It's amazing how we're replaying the asbestos playbook a century later. Only this time it's government mandated.
- rrr_oh_man 10mo ago> It's amazing how we're replaying the asbestos playbook a century later Can you elaborate?
- wincy 10mo agoI’m guessing the Russian theory that asbestos is totally fine and isn’t harmful? The Russians still use asbestos and say it’s a plot by the west that we got rid of asbestos in our buildings. (Don’t shoot the messenger here, I have no dog in this fight and am not expressing an opinion)
- orbital-decay 10mo agoYou are expressing disinformation. The actual regulations are very different from what you make it seem.
- throwaway173738 10mo agoAsbestos is totally safe as long as it’s not friable and you don’t sand it or disturb the fibers. Mesothelioma was a major problem if you were repeatedly exposed to asbestos. It’s present in nature and especially in soil in small concentrations. What makes it dangerous is if you’re constantly breathing it in. You would be doing that if you ran a buffer over asbestos tile for years, or if you worked in a space with asbestos pipe insulation, or if your job was to install asbestos siding or sheet flooring or formica(many adhesives contained it). Even gypsum wallboard contained asbestos up through the 80’s. It’s precisely its ubiquity as a building material that makes it dangerous because people are constantly disturbing it occupationally.
- orbital-decay 10mo ago
- AshamedCaptain 10mo agoWhy is it that right now there is still on the frontpage of an "article being found flawed after 6k citations " ( https://statmodeling.stat.columbia.edu/2026/01/22/aking/ https://statmodeling.stat.columbia.edu/2026/01/22/aking/ ) but this random article coming out of nowhere makes the front page on the same day? People really should get it and stop sharing newly published papers to the general public. The value of one single academic paper is exactly 0. Even a handful of such articles still has 0 value to the general public. This is only of interest to other academics (or labs, countries, etc.) who may have the power to reproduce it in a controlled environment. Be very skeptical of correlations like this that have dubious or poorly understood causation. Be even more skeptical if they are about day-to-day stuff that would likely have large swaths of people able to reproduce something like it on huge scales yet they haven't. Extraordinary claims require extraordinary evidence.
- novok 10mo agoYou can also look at all the papers it's citing too...
- angry_octet 10mo agoThis article is not making an extraordinary claim, and your offence is hyperbolic. Analysis of research should not be restricted to the academe, but careful not to cherry puck research.
- boxed 10mo agoIt seems like a pretty extraordinary claim to me. Considering the percentage of live mitochondria that are exposed to external light in a human this seems like an enormous effect. The effect we'd expect from publication bias though is already pretty big. I'm going to go with the latter until we've got some replication, and a plausible mechanism (like.. why wouldn't whales be badly sick if this was a thing?).
- angry_octet 10mo agoI don't know about the mitochondria bit, but it is plausible that work performance is affected by light spectrum. The n=22 is too small, but replication or larger studies is an obvious next step. Let's hope the researchers in this field use pre registration.
- HNisCIS 10mo agoNo mention of CRI which seems kind of odd. LEDs for lighting are increasingly graded by how natural their emission spectrum is. Older lights are quite bad, newer ones sacrifice a tiny bit of performance for more uniform spectrum.
- novok 10mo agoCRI is a pretty bad rating system. They are showing the full spectrum graphs which is what you'd want anyway. Spectral Similarity Index (SSI) is the better number
- HNisCIS 10mo agoSure, but I don't see them mention what they're actually using for LEDs at all. They mention a "colour fidelity index" but I'd expect a manufacturer part number or something so I can pull the datasheet. Funny enough, the best evidence for this study is that they should probably move somewhere with more sunlight if they can't spell "color" right... /s
- hedora 10mo agoThey use rf numbers, which is a newer standard, so that's probably good. However, the experimental group (extra light sources) got rf 91 bulbs, and the control ("LED lighting") got rf 85 bulbs. The two scales are not exactly comparable, but they both max out at 100. The only source I could find that discusses both says that > 90 CRI is "excellent" and just below that is "very good". It says > 85 rf is "very good", which tells me it's comparable to a mid-80's CRI bulb. If I accidentally buy a mid-80 CRI bulb, I either return it to the store, or just throw it away. So, I'd say this study's experimental setup doesn't support any useful conclusions. They showed that so-painfully-bad-California-won't-subsidize-them LEDs are worse than passable LEDs with supplementation from another light source. The passable LEDs in the study are probably comparable to the cheap ones at our local hardware store, but worse than the ones that cost $10-20 on amazon ten years ago. This would have been much more interesting if they'd compared high-end LEDs with and without supplementation, and found a difference. (And by "high-end", I mean "still much cheaper then the electricity they save")
- marcosdumay 10mo agoJust to point to anybody that comes here directly, the article has no relation at all with perceived illumination, color fidelity, or anything else people complain about leds. It's an interesting niche topic that you may want your working place to notice if you work indoors.
- herf 10mo agoThere is a 15-30% difference between the groups at baseline (fig 8c-9c, 8d-9d), about the same magnitude as the claimed effect of the experimental condition. I think the result would be much stronger if these baselines were comparable, so they show they have accounted for other variables like time of day and light history. I am also skeptical of any effect in the retina lasting 6 weeks, with no fading. Consider that people are often exposed to much more infrared light outdoors, so "worked under a relatively dim incandescent lamp" is not a particularly novel stimulus. Imagine that any of these people spent time outdoors during the six weeks - thousands of times more infrared light there.
- londons_explore 10mo agoIndeed - these study results are fairly substantial if they can be independently reproduced by more studies at bigger scales.
- bob1029 10mo agoI've been using incandescent more often. All my vanity lights are 40w appliance bulbs now. The difference at night is remarkable. The LED is just too much even at 2700k. I still prefer LED for high power situations like br30/40 can lights.
- PeterStuer 10mo agoWas just discussing last week with a colleague how for the same 'lumen' there was such a dramatic difference between led and incandescent bulbs for ease of reading paper books.
- Cthulhu_ 10mo agoWhich one of the two was better for it?
- PeterStuer 10mo agoIncandescent, by miles. Not even in the same ballpark. Even just candlelight beats led.
- adrian_b 10mo agoThere are very great differences in light quality between various kinds of LED lamps. You may have various LED lamps, all of which appear to have the same white color, but their spectra are very different. Those with narrow spectral peaks are very bad lighting sources, while those with wide spectral peaks, achieved by using multiple kinds of conversion phosphors, are much better lighting sources. With the best LED lamps, there is not much difference in comparison with incandescent lamps. While incandescent lamps are best from the point of view of their continuous spectrum, their yellow light strongly modifies the perceived colors. While bluish white LEDs (e.g. of 6500 K color temperature) are also bad, neutral white LEDs (e.g. 5000 K or 5500 K) provide much better color perception than incandescent lamps. For home lighting I prefer a white that is only very slightly yellowish, i.e. 4000 K lamps, instead of LED lamps with a higher color temperature or of incandescent lamps, which are so obviously yellow that no clothes have the same color as in daylight. The best quality of lighting can be achieved by incandescent lamps in conjunction with frequency-selective filters, which modify their spectra to resemble the spectra of a blackbody with a higher temperature, like the Sun. Such filtered incandescent lamps were used a very long time ago, to provide lighting for color photography, movies and television (e.g. for the original white point of NTSC), but they were abandoned due to high cost and due to an exceedingly low energy efficiency. As I have mentioned in another comment, filtered incandescent lamps might see a revival, but implemented with very different technologies than those used a century ago.
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- accidentallfact 10mo agoI don't think that this is the reason. Yes, there is something obviously wrong with most LED lights, but it isn't too much of short wavelength light, but on the contrary. It's the near absence of cyan light in most LEDs. Our eyes are by far the most sensitive to it, the majority of receptors in the eye are sensitive to it, and we may focus primarily on it (focus differs for different wavelengths). This is how you get the feeling of something being wrong with your vision as you for example walk into a mall, and so on. If anything, higher temperature lights seem to make it better, not worse, but the problem will persist as long as the cyan hole stays there.
- guenthert 10mo agoSensitivity peak for humans is in cyan (~510nm) only for low-light conditions (night vision / rod cells). In daylight (cone cells) it's green-yellow (555nm). https://www.giangrandi.ch/optics/eye/eye.shtml https://www.giangrandi.ch/optics/eye/eye.shtml
- accidentallfact 10mo ago>The eye behaves differently in high or low light conditions: in daylight, for brightness levels above 3 cd/m2 the vision is mainly done by the centre of the retina, we can see colors and the maximum sensitivity is at 555 nm (in the green region). This type of vision is called photopic vision. That's completely impossible, you would have severe tunnel vision in daylight, if it was true. There has never been any real evidence that rods stop working in daylight.
- accidentallfact 10mo agoHere you can see that cones only extend to 2° from the center. I think it's illegal to drive with less than 20°FoV. https://www.google.com/search?client=ms-android-samsung-rvo1&hs=bIu9&sca_esv=6a0b219675808712&udm=2&fbs=ADc_l-aN0CWEZBOHjofHoaMMDiKpaEWjvZ2Py1XXV8d8KvlI3lB6BRmAv9Tdx4SvL4ZREsvAtO7uvBzcA2nI7Y2smQuOcOD1BRIJlYEP9L184wHplUnDJZldrEB9OrnQhro058BtHQi8SjOi7hgEVYTYNC4yFp6wV67XyBoBwgLNG_K6icd74SWNfqaojX3OWwqk_7UYMP03hPB86wRBy18I_YUyr-l_mg&q=cone+density&sa=X&ved=2ahUKEwijtcO2oKuSAxWfgP0HHYQhNR8QtKgLegQIEhAB&biw=411&bih=747&dpr=2.63&aic=0#sv=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_LfECDABSgoIARACGAIgAigC https://www.google.com/search?client=ms-android-samsung-rvo1...
- adrian_b 10mo agoIt should be noted that even if we assume that the conclusion of this study is correct, i.e. that artificial lighting should have a wide spectrum including near-infrared light, that does not mean that returning to classic incandescent lamps is the right solution for this problem. The incandescent lamps with tungsten filaments have a much lower temperature than the Sun, thus much more energy is radiated in infrared than needed. There was about a year or two ago a discussion about a very interesting research paper that reported results from testing an improved kind of incandescent lamp, with energy efficiency and lifetime comparable to the LED lamps. The high energy efficiency was achieved by enclosing the lamp in a reflecting surface, which prevented energy loss by radiation, except for a window that let light out, which was frequency-selective, so only visible light got out, while infrared stayed inside. The lamp used a carbon filament in an environment that prevented the evaporation of the filament. With such a lamp, one can make a tradeoff between energy efficiency and the content of healthy near infrared light, by a judicious choice of the frequency cutoff for the window through which light exits the lamp. Even with enough near-infrared light, the efficiency should be a few times higher than for classic incandescent lamps, though not as good as for LED lamps. Presumably, one could reach an efficiency similar to that of the compact fluorescent lamps (which was about half of that of LED lamps), for such an incandescent lamp that also provides near-infrared light.
- lgeorget 10mo agoHow does enclosing the lamp in reflective material help with the energy efficiency? Isn't the infrared radiation emitted anyway? Doesn't that make the lamp overheat?
- adrian_b 10mo agoIf the reflective material is ideal, by definition no infrared or other radiation is emitted. Perhaps I was not clear, but the reflective surface was the interior surface, so it reflected any light, visible or infrared, back towards the emitting filament, while the front window reflected only the infrared, while transmitting the visible light. The lamp does not overheat, because the filament is kept at a constant temperature, the same as in a classic incandescent lamp. The difference is that you need a much lower electrical current through it for maintaining the temperature, because most of the heat is not lost away, like in a classic lamp. The fact that you need a much smaller electrical current for the same temperature is the source of the greater energy efficiency. Only if you had used the same electrical current as in a classic lamp, the lamp would have overheated and the filament destroyed, but you have no reason to do that, like you also do not want to use in a classic lamp a current higher than nominal, which would overheat and destroy it.
- wtcactus 10mo agoI found some interesting tidbit about this bigger issue. And I want to share how to more easily check it. We many times see some people reporting that they clearly see lower quality LED light flicker and is really distracting to them and even causes them headaches. Now, I didn't see this until recently (unless in failing lights) in the right conditions. If the light is very, very dim: For instance, only 1 light on in the night, and you are in a division far away from the light so that it's extremely dim. There, I could finally really see it flicker. I've replaced that light for a better one and the effect went away.
- deleted 10mo ago[deleted]
- schiffern 10mo agoScientific Reports is a junk journal fyi. Not conclusive, but indicative. Despite saying the visible flux component is "small" and that the tungsten lamps "were not expected to [be used] as task lamps," Figure 6 (a) and (c) shows... desk lamps right at the work stations like task lamps! Not only is this experimentally unblinded, but the visible light immediately in front of the test subjects is noticeably brighter and warmer. The effect could simply be due to reduced eye strain. What would James Randi do? "Extraordinary claims require extraordinary proof," and unfortunately this isn't it. This would be more interesting if they add a visible light filter on the lamps so they only emit infrared radiation, and have an identical double-blind control with a 60 watt heater bulb so it emits no SWIR but the same radiant heat (which could confound and/or unblind).
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- zahirbmirza 10mo agoThe push toward LED seems to be primarily for emission target related reasons. It is very hard to buy incandescent bulbs in the UK; even for those of us that accept the cost implications. Also, many less expensive LEDs flicker at the rate of the frequency supply of the current (ie 240 or 120 Hz). This is very annoying and related to the instantaneous response of LED vs the averaging effect of the alternating current through an actual glowing hot filament. It is interesting to read on the development of blue and white LED technology.
- oniony 10mo agoIf I were able to see the flicker of mains supplied LED lighting (which I cannot), then I would be very tempted to install low-voltage DC LED lighting, which presumably does not flicker.
- lightedman 10mo agoIt only doesn't flicker if there's no power driving circuitry - eg just LEDs and a resistor. Otherwise, if there is a power IC present, there is flicker, though fast enough for most humans to not perceive normally (you can still check it by waving your hand in front of the light and seeing the strobed afterimage.)
- zahirbmirza 10mo agoYes! And this after image is distracting.
- mnw21cam 10mo agoThat's not strictly true. The very simplest of DC LED drivers flicker, such as the classic single-transistor battery saver circuit, but a slightly more complex DC LED driver circuit will not. One of the best ways to drive an LED is with a constant current source, which typically involves putting an inductor in series with the LED and switching the supply to that at a reasonably high frequency, which would mean the LED does not flicker at all.
- 10mo ago
- kalium-xyz 10mo agoThis should also be true for TL lights. Which kinda contradicts common sense seeing that those are used all over the place in offices, kitchens, and hospitals, makes me think this paper is bogus.
- DeathArrow 10mo agoIn EU, the ROHS directive forbids even more types of lightbulbs, beside incandescent: Ban on all fluorescent tubes (T5 and T8 lamps) from August 24, 2023 Ban on all CFL lamps from February 24, 2023 Extension of the exemption granted to HPD lamps from 3 to 5 years Extension of the exemption for special purpose lamps from 3 to 5 years
- DeathArrow 10mo agoThere are some full spectrum led lights, they just cost over $100 a piece. And they might get banned in the future for not being energy efficient enough.
- r_lee 10mo agoI hate the LED street lamps so much. I can tell they've got a really spiky and unnatural spectrum, unlike the HPS lights, not to mention that they're white or bright yellow...
- zahirbmirza 10mo agoI miss the orange glow of sodium lamps that characterised cold dark and foggy english winter nights.
- r_lee 10mo agoYup. Even to this day when I'm on the bus on the highway it's so relaxing and comforting to ride through the orange lights.. then the bright white ones come through and it's almost like instant anxiety that kicks in
- nrjames 10mo agoI’ve always been mildly bothered by the LED lighting in my home, as if it’s simultaneously bright but not illuminating. In simple consumer terms, if I wanted to shop for a variant that more closely replicated incandescent lighting, what exactly am I looking for on the packaging? Or does this not exist?
- atopal 10mo agoIt’s called SSI, spectral similarity index. SSI is specified for a color temperature, eg 3200 or 5600. 100 is identical to tungsten or sunlight. Values above 85 are good.
- yarekt 10mo agoIn the UK I've not been able to find high wattage (10-20W) LED lightbulbs with high CRI, some don't even mention it in listings, let alone SSI, which I have never seen. Where are you seeing these? Is this industrial/commercial suppliers?
- johanvts 10mo agoPhillips, try searching for EyeComfort. I think all of their premium bulbs have 80+ Ra.
- graemep 10mo agoThey look good, but cannot find a listings with all the details though to know exactly what I will get if I buy them. It is a good start and I know know its wroth looking, so think you.
- schiffern 10mo agoGE Relax is my preference, with 93 Ra. A good all-around bulb. https://www.housebeautiful.com/shopping/a31139492/ge-relax-led-bulb/ https://www.housebeautiful.com/shopping/a31139492/ge-relax-l...
- atopal 10mo ago
- ck2 10mo agoever since they replaced streetlamps with led (like a decade ago?) I can't see anything anymore before dawn there may be more light (photons) but their spectrum is too limited for my eyes to see like halogen, etc. I still only use compact florescent in my home, led is useless to me
- analog8374 10mo agoAlso, LED strobes to dim. Which is unpleasant.
- elric 10mo ago> In humans a single 3 min 670 nm exposure improves colour vision within 3 h, which is sustained for almost a week That seems remarkable and almost too good to be true?
- hnuser123456 10mo agoSeems like this is only relevant for people who don't go outside for weeks at a time? This article has a strangely "pro-long-wavelength" tone, yet sunlight also exposes you to UV frequencies that are so harmful according to this paper.
- blacklion 10mo agoIt was known among MTB riders who ride at night sometimes: typical XM-L T6 Chinese headlights were unusable in the forest when you move fast. Good diodes (like Nichia 219B) worked. And XM-L was dominant even in very expensive «brandnamed» lights for many years (you could buy Aliexpress headlight for $20, you could bu "Italian" lamp for $250, result is the same) I'm not in this scene anymore for many years, but when I was, I built my one lamp from custom light engine (essentially round PCB with DC-DC current limiting schematics an LEDs) with 3x219B, Chinese body and CARCLO TIR Optics... Good times.
- mikkupikku 10mo agoI have a theory that cheap LED lights with low quality drivers are bad for dogs. LEDs with low quality drivers very often have a high amplitude flicker at 50/60Hz, which is about the flicker fusion rate for humans so we don't perceive it (at least usually), but dogs are known to have a substantially higher flicker fusion rate and probably perceive the flicker. Probably worth considering, especially if you have a dog with epilepsy. (Incandescents also flicker at 50/60Hz of course, but the thermal inertia of the filament makes this a lower amplitude flicker.)
- buildbot 10mo agoIf you are sensitive you can get really, really annoying blips of flicker even above 1khz - https://journals.sagepub.com/doi/10.1177/1477153512436367 https://journals.sagepub.com/doi/10.1177/1477153512436367 They also flicker really badly if your power is not perfect, like you have a decent sized training rig on a different circut. Incandescents are basically little light inductors and I would imagine the luminosity curve would be sinusoidal vs whatever hell a LED driver chip puts out.
- countWSS 10mo ago> (at least usually). Nope. Lots of people see the strobing. Its causes headaches if you focus on the lights.
- entropie 10mo agoBesides the epilepsy, what do you mean with "bad for dogs?" Sidenote: My partner and me both "feel" the difference of cheap LEDs. Its not something we can pinpoint down, but it got way better with hue lights. We live with multiple dogs and iam really curious. One of the dogs that we often had around had severe epilepsy that very strong medication was needed and the dog died anyways way to early around the age of 2. She had less sizures than in her original home when she was with us which ofcourse might be unrelated to the lighting. But your thought is interesting.
- mikkupikku 10mo ago> Besides the epilepsy, what do you mean with "bad for dogs?" Psychological or physiological unease at least, I assume this from the way rapidly flickering dying florescent lights make me feel.
- daveloyall 10mo agoThe authors, bless their hearts, suggest that running halogen lamps at lower-than-rated voltages might be a good idea. > If this is done with a halogen bulb, which is a type of incandescent tungsten bulb, the filament lasts for a longer period as evaporated tungsten is redeposited on the filament rather than blackening the bulb glass. Hence, using a halogen bulb at lower voltage is a realistic alternative in terms of health and energy consumption. Unfortunately, as I understand it, the redepositing action only occurs at high temperatures.. It's a chemistry thing. I have been led to believe that running halogens at low voltages will cause the bulb glass to blacken sooner. See https://en.wikipedia.org/wiki/Halogen_lamp#Effect_of_voltage_on_performance https://en.wikipedia.org/wiki/Halogen_lamp#Effect_of_voltage...
- pedrocr 10mo agoOne of the authors of this paper did a pretty long podcast with Huberman about this topic: https://www.hubermanlab.com/episode/red-light-to-improve-metabolism-and-harmful-effects-of-led-glen-jeffery https://www.hubermanlab.com/episode/red-light-to-improve-met... The show notes have links to quite a few more papers. I have no idea if this is good science but this is not just a one off paper.
- mikeyouse 10mo agoIt’s a shame that grift claims everything.. once upon a time, Huberman was a serious person but he’s now just Joe Rogan with an advanced degree - platforming all sorts of bullshit for a check. At least there are other sources listed though so thanks for those.
- schiffern 10mo agoIt's junk science. https://news.ycombinator.com/item?id=46764382 https://news.ycombinator.com/item?id=46764382
- dwroberts 10mo agoI find it a little strange that there is no real discussion of limitations in this paper. They mention the limitations of something they cite, but nothing about the data they themselves collected or the conclusions they draw from it
- schiffern 10mo agohttps://news.ycombinator.com/item?id=46764382 https://news.ycombinator.com/item?id=46764382
- roughly 10mo agoYou know, it's funny - there's a couple places where this kind of thing seems to have come up. There's research around crop nutrition levels that shows decreases in nutrient levels as yield per acre goes up, there's research on supplements and vitamins that shows synergistic effects between seemingly unrelated substances, we've seen surprising effects from adding or removing species from an ecosystem. One begins to suspect that the "reductive" method of science - the sort of physics- or mathematics-type "reduce the variables of the problem until we can isolate effects" approach - isn't particularly well-suited to dealing with biological systems. You see it in bioinformatics as well - we've sequenced the genomes for many organisms, and have learned a lot from doing so, but we're also learning the limits of that approach pretty strongly - the organism isn't defined just by its 'code', but its environment; the presence, distribution, and concentration of various chemicals; etc. I suspect as we move more towards the "biological" century here we're going to have to readjust how we approach things to start trying to find those synergistic effects earlier in the process, rather than pull everything down to its constituent parts and then experimenting pairwise with various combos. I get the difficulties in doing that, but I feel like we've repeatedly found the stuff we've discarded as irrelevant to the problem ("things that are not in the visual wavelength the eye perceives") in fact do wind up being relevant (wider full-spectrum light has effects outside the mere spatial perception of objects).
- nazgul17 10mo agoCould it be the pendulum swinging hard before selling in the middle? Once we learn from our mistakes we can find the frequencies that do yield the best outcome and at the same time consume (say) ¼ the energy of an incandescent bulb. Or the minimum set of species yielding optimal outcomes, without the answer being "all of them"
- BizarroLand 10mo agoSounds like a holistics approach will be the next big swing of scientific endeavor. That was the original point to begin with, right? Learn what makes things tick and then build on that. We've got enough of it down to the atomic level that maybe we should zoom back to the supermolecular.
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- iagorodriguez 10mo agowouldn't this be a good thing? I prefer my circadian cycles not to be disturbed by artificial lights and if i am reading this right, it is what happens with led lights. this would be different of course if i had no access to natural lights. glad to be corrected :)