[HN Gopher] Blue light filters don't work - controlling total lu...
       ___________________________________________________________________
        
       Blue light filters don't work - controlling total luminance is a
       better bet
        
       Author : pminimax
       Score  : 222 points
       Date   : 2026-02-20 18:14 UTC (1 days ago)
        
 (HTM) web link (www.neuroai.science)
 (TXT) w3m dump (www.neuroai.science)
        
       | snet0 wrote:
       | But have you considered that it _feels_ better?
        
         | stronglikedan wrote:
         | so do placebos
        
           | kurthr wrote:
           | I agree for sleep. I prefer them because they focus better
           | for me.
           | 
           | Blue creates a halo around letters that is distracting with
           | my declining vision.
           | 
           | Also, Blue fluorescent OLED are ~50% less efficient than R/G
           | phosphorescent OLED so you can reduce screen power
           | consumption of a full white page by almost 30% using such a
           | filter. That in turn might be 30% of active device power
           | consumption (for a total of almost 10% in battery life during
           | active operation). Ignoring that they also tend to burn out
           | more quickly, since tandem blue has become fairly mainstream.
           | 
           | Many more reasons for these "filters", if you don't mind the
           | white balance shift and reduced color gamut.
        
           | snet0 wrote:
           | So what? If I could take a sugar pill that guaranteed I feel
           | comfier looking at my screen, nobody can tell me it "doesn't
           | work". I'm not trying to optimise my life, I'm trying to have
           | my eyes feel better.
        
             | Barbing wrote:
             | Placebo and "manifesting"--the latter sounds mockable but
             | pretty much the same thing, harmless if helpful so hey!
        
               | nickthegreek wrote:
               | The placebo effect is a real, measurable mind-body
               | response where belief & expectation can change your
               | symptoms or how you feel. However, it does not directly
               | alter external reality. Manifesting claims your thoughts
               | or intentions can cause _outside events_ to happen, which
               | has zero evidence to support it.
        
               | mikkupikku wrote:
               | If somebody is "manifesting" themselves a sleep aid, I
               | think they'd just call it meditation and everybody would
               | more or less accept that it probably works for that
               | individual. Maybe you'd have a few people with severe
               | autism who start arguing on online forums about the
               | scientific evidence behind meditation, but that's just
               | them being them.
        
           | tshaddox wrote:
           | Not really. Most of the cultural notion about the remarkable
           | effects of placebos came from flawed studies in the 1950s. As
           | far as I can tell, the modern consensus is that there's no
           | clinically significant placebo effect _except_ for conditions
           | that can only be measured by a subject self-reporting their
           | own perception (like pain and fatigue).
        
           | allthetime wrote:
           | and? placebo is often effective.
        
       | debo_ wrote:
       | > Everybody wants better sleep
       | 
       | Bro, as someone who had brutal insomnia for a couple of years and
       | now sleeps "normally" for whatever that means, I can tell you
       | that I don't think about my sleep quality at all. I'm happy to be
       | sleeping.
       | 
       | If you too sleep "ok" for whatever that means, maybe stop
       | worrying about optimizing it and go do something else less
       | insane.
        
         | loloquwowndueo wrote:
         | What did you do to tackle your insomnia?
        
           | smt88 wrote:
           | Primary, idiopathic insomnia doesn't really exist. It's
           | almost always anxiety, although a few other mental and
           | physical conditions can also cause it. But more likely
           | anxiety.
        
             | debo_ wrote:
             | That was my experience as well.
        
           | m3047 wrote:
           | Disturbed sleep / inability to settle / anxiety can have
           | physical causes although these are poorly recognized /
           | diagnosed by regular allopathic medicine where I live.
           | 
           | Anecdata: 1) A good friend whose anxiety was largely
           | alleviated (and sleep improved) by recognizing and treating
           | their iron deficiency. 2) I have to (can't take the Western
           | drug which was prescribed any more, and the Western doctors
           | can't seem to bang the rocks together) take herbs for my
           | hypertension but as opposed to the side effects I was
           | experiencing from the drug I joke that all of the "side
           | effects" from the herbs are good, they're targeting
           | imbalances which were not recognized / treated previously and
           | lo and behold I settle and sleep better... which helps reduce
           | the blood pressure.
        
             | debo_ wrote:
             | Which herbs do you take?
        
               | m3047 wrote:
               | I would discuss this with you in some detail privately,
               | with bona fides. You should consult with an herbalist.
               | The herbalist I see doesn't mix themes / traditions. The
               | one we've chosen, together, to work with is TCM. Inside
               | of TCM there are "strategies" or themes. We tried a few,
               | the gou teng + tian ma theme seems to work, minor changes
               | happen seasonally. Underneath that are herbs addressing
               | inflammation (ability to settle / get comfortable),
               | immune system (allergies) balancing (post nasal drip /
               | congestion / anxiety), circulatory health (e.g. cold
               | feet), and tonifying some of the major metabolic /
               | detoxifying organs (sweating / digestion). I have a
               | renewed commitment to exercise and making sure I eat the
               | right things for my body.
               | 
               | In the beginning I got hit with something and was
               | misdiagnosed, and almost died; hypertension didn't fit
               | the narrative so was initially ignored. By the way, when
               | you don't sleep for three months it fucks you up. No
               | attempt was ever made to even acknowledge that there
               | might be a root cause for the hypertension. The
               | hypertension drugs worked until they didn't, and they
               | started gaslighting me about it. Bear in mind, in the
               | context of the theme better sleep will help with
               | hypertension (demonstrably true!).
               | 
               | You need to cultivate awareness as well as evidence-based
               | skepticism for this to work. One of the herbs I take
               | interacts with the beta blocker I still take, and if you
               | weren't paying attention it could kill you (nobody told
               | me, or the herbalist, about it). Some of the herbs are
               | pricey, but none are over $80/pound. All in, it costs me
               | about $100 / month, and two hours of my time every three
               | days (to boil herbs). Quite frankly, if the pills work
               | then just do that; but don't treat it as a "solve", get
               | to work and identify some of the root causes and what can
               | be done about it... before they stop working or start
               | making you sick.
        
           | debo_ wrote:
           | I spoke about it in this video:
           | https://www.youtube.com/watch?v=QnNPRqLVtaM
        
         | nine_k wrote:
         | Waking up tired and with the brain full of fog is nearly as fun
         | as not sleeping and ending up tired, with the brain full of
         | fog. Truth be told, most cases of "poor sleep quality" are not
         | as brutal though.
        
         | kqr wrote:
         | The charitable reading of "better sleep" is "sleep habits that
         | allow for a healthy amount of sleep". A lot of people have
         | habits that give them insufficient sleep.
        
           | jerlam wrote:
           | Yeah, "get better sleep" is usually followed with "by buying
           | this thing". No one makes any money if you go to sleep
           | earlier.
        
           | debo_ wrote:
           | My experience is being surrounded by people who sleep eight
           | hours a night and then check their ring data or whatever
           | nonsense to convince themselves that they could do better.
        
       | koalacola wrote:
       | Is this your article OP?
        
       | aethrum wrote:
       | They absolutely help my eyes not be so strained. If its placebo,
       | its a working placebo.
       | 
       | >Are people actually using Night Shift? >Aggravatingly, yes.
       | 
       | What is the authors problem lol? It feels a lot better on
       | eyeballs to use warm light things. Why does he care?
        
         | thenewnewguy wrote:
         | I'm not an MD or expert in this field enough to know if OP is
         | right or wrong, but I think it's fairly reasonable to be
         | irritated people are claiming software has a health benefit
         | based on vibes/feels.
         | 
         | I thought we as a society had moved on from superstition to
         | evidence-based medicine, but in this very post there are plenty
         | of replies countering OP's scientific analysis and data with
         | anecdotes (which is disappointing regardless of if TFA is
         | correct or incorrect).
        
           | geoduck14 wrote:
           | >I think it's fairly reasonable to be irritated people are
           | pushing software based on vibes/feels.
           | 
           | You are going to HATE to find out about night-mode in the
           | browser
        
             | thenewnewguy wrote:
             | To be fair, I should have said something like "claiming
             | software has a health benefit based on vibes/feels". I
             | personally prefer the look of night/dark mode (or whatever
             | you call it) in apps and the browser, but I'm not going to
             | claim it makes me healthier or improves my sleep or
             | whatever.
             | 
             | If you just like how something looks, that's fine, but
             | there's a difference between "I like how X looks"
             | (subjective opinion) than "X helps me sleep better"
             | (difficult to prove but objectively true or false).
             | 
             | Edit: Changed this in my original message as it seems
             | multiple people got confused by my prior poor wording.
        
               | thatcat wrote:
               | It's not about how it looks aesthetically, you can feel
               | your eye muscles release tension when you go from light
               | to dark mode.
        
               | IAmBroom wrote:
               | As someone more trained in science than software, the
               | phrase "you can feel..." is suspicious, _even if_ it 's
               | my own feelings.
               | 
               | Not invalid; suspicious.
        
               | nandomrumber wrote:
               | As a complete psychopath:
               | 
               | If I put your hand in a vice _and_ do the vice up to the
               | point where you start saying you _can feel_ the
               | pressure...
               | 
               | Yes, of course I'm going to be _suspicious_.
               | 
               | Gaslighting doesn't exist, you made that up because
               | you're _fucking crazy_.
               | 
               | /s
        
               | thatcat wrote:
               | A phrase like I'm more trained in science is an appeal to
               | authority, which is pretty suspicious, as is not trusting
               | your own observations. How do you trust the data you
               | collect?
               | 
               | feel in this case is a muscle contraction not
               | psychological as you're suggesting
        
               | wtetzner wrote:
               | Regardless of "health benefits", the phrase "you can
               | feel" seems pretty relevant when it comes to what someone
               | finds comfortable.
        
               | 0x1ch wrote:
               | End of the day, dark mode would've been totally ignored
               | if there wasn't a perceivable benefit, placebo or not.
               | People want to make everything difficult, I guess.
        
               | tcfhgj wrote:
               | Benefit: saves battery on OLED and goes easier on the
               | OLEDs themselves
        
               | theshackleford wrote:
               | > you can feel your eye muscles release tension when you
               | go from light to dark mode
               | 
               | For those like me, i'd like to add, this is not
               | universally true. For some, dark mode will provide a
               | significant reduction in comfort and increase in your
               | fatigue and other symptoms.
               | 
               | Quite a few years back now, I started having significant
               | problems with my eyesight that for the longest time I
               | failed to match up to the switch to significant dark mode
               | usage.
               | 
               | Turns out for many (though perhaps not all) with
               | astigmatism, dark mode can induce issues that will wipe
               | any potential positive impacts normal people experience.
               | In my case, it gave me horrific blurryness/double vision
               | that I thought was my eyes developing some new problem.
               | 
               | I'd tell the eye doctors "it seems to start fine then get
               | worse as the day goes on!"
               | 
               | No, in fact what was actually happening, was in the
               | afternoon my machines were scheduled to start shifting to
               | dark mode. At which point the issues would start and my
               | eyes would feel "heavy." It would fatigue my eyes so
               | heavily that even not looking at displays would be
               | affected.
               | 
               | I can not believe it took so long to connect the two, but
               | I never even considered dark mode because it was so
               | heavily pushed (along with reductions in brightness) as
               | the answer to general monitor usage fatigue that I never
               | remotely considered it may do the opposite, which to be
               | fair, is on me.
               | 
               | Point is...if you have astigmatism, verify for yourself
               | before rolling over to the full commit. Hopefully you are
               | fine, but if not, you'll know why.
        
           | jack_pp wrote:
           | Is it superstition to deduce that I get gassy after eating
           | beans? I need a scientific study to tell me this? Same for if
           | a screen hurts my eyes (not long term, like truly my eyes
           | hurt) when using bright white colors at night.
        
             | thenewnewguy wrote:
             | Yes, actually, if someone has direct scientific evidence
             | contrary to the claim (I doubt such evidence exists for
             | your first example as to the best of my knowledge the
             | relationship between beans and gastrointestinal changes is
             | well understood).
             | 
             | Your eyes could hurt for a variety of reasons - brightness,
             | too long screen time, being dry for external reasons, etc.
             | Most humans are poor at identifying the cause of one-off
             | events: you may think it's because you turned on a blue-
             | light filter, but it actually could be because you used
             | your phone for an hour less.
             | 
             | That's why we have science to actually isolate variables
             | and prove (or at least gather strong evidence for) things
             | about the world, and why doctors don't (or at least
             | shouldn't) make health-related recommendations based on
             | vibes.
        
               | jack_pp wrote:
               | It's pretty clear, even on monitor, night and day
               | difference at a push of a button. I'm not arguing if this
               | helps you sleep better but it is pretty arrogant of you
               | to tell me I can't figure out from my own experience if
               | something is comfortable or not.
        
               | BobaFloutist wrote:
               | Nobody really cares if it's comfortable or not _for you_
               | , the debate at hand is whether it's measurably more
               | comfortable for _the population at large_.
        
               | cgriswald wrote:
               | That's how it _should_ be but the poster is literally
               | calling the individual experiences of others
               | "superstition" based on _the population at large_.
        
               | nandomrumber wrote:
               | It's about the equivalent of someone claiming my saying I
               | find woollen clothing directly touching my skin to be
               | irritating / itchy requires double blind randomised
               | controlled studies to determine whether this is true at
               | the population level.
               | 
               | There are eight billion of us, we can't _all be
               | different_ , there must be at least some categories we
               | can't be sorted in to, maybe those who find woollen
               | clothing itchy and those who don't, and those who find
               | blue-light reduction more comfortable and those who
               | don't.
               | 
               | One of my pet theories is that this hyper fixation on The
               | Ultimate Truth via The Scientific Method is what happens
               | when a society mints PhDs at an absurd rate. We went up
               | with _a lot_ of people who learn more and more about less
               | and less, and a set of people who idolise those people
               | and their output.
        
               | crazygringo wrote:
               | > _if someone has direct scientific evidence contrary to
               | the claim_
               | 
               | Except they don't. This is evidence about _one_ potential
               | mechanism. Not evidence saying there are _no other_
               | potential mechanisms.
               | 
               | This is actually a very common mistake in popular science
               | writing, to confuse the two.
        
               | wat10000 wrote:
               | If your eyes routinely hurt when doing something, and
               | then they stop routinely hurting after you make a change,
               | that's pretty good reason to believe that there's a
               | causal effect there.
               | 
               | Sometimes the causality is clear enough that you don't
               | need sophisticated science to figure it out. Did you know
               | that the only randomized controlled trial on the
               | effectiveness of parachutes at preventing injury and
               | death when jumping out of an airplane found that there is
               | no effect? Given that, do you believe there really is no
               | effect?
        
               | philwelch wrote:
               | I have direct scientific evidence contrary to the claim
               | that parachutes improve the safety of jumping out of
               | airplanes.
               | 
               | https://www.bmj.com/content/363/bmj.k5094
        
           | bob1029 wrote:
           | > I think it's fairly reasonable to be irritated people are
           | pushing software based on vibes/feels.
           | 
           | https://en.wikipedia.org/wiki/Video_game_industry
        
           | taco_emoji wrote:
           | > I thought we as a society had moved on from superstition to
           | evidence-based medicine
           | 
           | Surely you didn't actually believe that unless you JUST
           | landed here from space after being away for 60 years.
        
         | KaiserPro wrote:
         | because if you read the article its about blue light filters
         | _to aid sleep_ not ease of reading.
         | 
         | The the grift wheel on this particular bandwagon is strong. To
         | the point where my fucking glasses have a blue filter on them,
         | which fucks up my ability to do colour work becuase everything
         | is orange.
        
           | robinsonb5 wrote:
           | If you wait long enough cataracts will give you that for
           | free.
        
           | cpburns2009 wrote:
           | Blue light filtering lenses come at a premium. You don't
           | accidentally get them.
        
             | KaiserPro wrote:
             | I wasn't paying for them, so it was very much accidental.
        
               | pavel_lishin wrote:
               | Someone ran up to you and put them on your face?
        
               | mikkupikku wrote:
               | You should go back and demand they be replaced. Such a
               | mistake isn't something you should tolerate.
        
               | KaiserPro wrote:
               | I don't go to that optician anymore.
               | 
               | The list of mistakes were as follows:
               | 
               | 1) it corrected my eye with a slight astigmatism, but
               | over corrected my other eye, so the agregate was pretty
               | much the same
               | 
               | 2) the aformentioned blue filter, which is part of the
               | anti-glare coating.
               | 
               | 3) my non-astigmatic eye was incorrectly marked with a
               | prescription
               | 
               | 4) I don't actually need glasses because I can see to the
               | bottom of the eye chart without them. Its just as I'm now
               | older, my vision is not as good as they used to be.
               | 
               | 5) these were designed for "close work" but actually
               | don't really help me focus closer to me.
               | 
               | However, arguing that, as a non-proffesional with only a
               | passing understanding of optics (non-biological) with a
               | large multinational company doesn't seem like a good use
               | of time.
        
             | RupertSalt wrote:
             | Let me explain how many times I went back-and-forth with
             | the opticians about "is this coating/feature optional?"
        
               | cpburns2009 wrote:
               | My optician's office charges an extra $100 for blue light
               | filtering. They at least make it clear it's optional but
               | recommended for frequent screen use.
        
         | tartoran wrote:
         | I confirm that this helps me as well. Quite often I don't have
         | any fancy filter, I'm permanently setting display/monitor to
         | low temperature and my eyes/vision couldn't be happier. I don't
         | even need darkmode, regular mode works just fine for me as long
         | as blue light is toned down. Granted, I'm not doing any color
         | correction or anything color sensitive work.
         | 
         | I used to have terrible headaches about 20 years ago when I
         | started spending a lot of time in front of the screen. I went
         | to an optometrist who tested my eyes and told me I could get
         | low prescriptions (.5) but warned me that there's no way back
         | and that many people are fine with my current vision, choosing
         | not to get a prescription. Luckily I figured out that it was
         | blue light that was bothering me and once I turned it down I
         | haven't had any problems since. I'm in my mid 40s and my vision
         | has naturally deteriorated a bit but I am still fine with no
         | prescriptions.
         | 
         | And I don't believe this to be placebo. Every time I stare at a
         | regular screen for longer than 5 minutes I get eye strain. At
         | the same time I suspect this doesn't help everyone, but at
         | least to me this is a great solution that still works.
        
           | cellularmitosis wrote:
           | Can you elaborate on "no way back"?
        
             | denkmoon wrote:
             | Not OP, but when I got glasses as an adult and while they
             | really improved the sharpness of my vision I could feel my
             | unassisted vision getting worse, so I stopped using them
             | and get by with slightly unfocused but unassisted vision. I
             | assume if I wore them full time my unassisted vision would
             | degrade to the point where I then need the glasses full
             | time.
        
               | ifwinterco wrote:
               | I've got half a diopter (ish) of astigmatism in my right
               | eye and it can be slightly annoying but interesting to
               | know that using glasses would risk making it worse.
               | 
               | The weird thing is it seems to get noticeably worse or
               | better depending on how much time I spend outside
        
               | pseudalopex wrote:
               | Your assumption was false.[1]
               | 
               | [1] https://health.clevelandclinic.org/do-glasses-make-
               | your-eyes...
        
               | maccard wrote:
               | I got glasses 2 years ago for a very minor prescription.
               | Your eyesight sucked before you've just forgotten how
               | badly. I had an eye test very recently for Contacts and
               | my prescription is the same 2 years later
        
             | tartoran wrote:
             | I meant that once you decide to wear prescription optics
             | you can't go back to not wearing them, of course excluding
             | eye surgery. In my case I could stick to good enough vision
             | and luckily 20 years later Im still not wearing glasses. My
             | main point was that I was getting eye strain from blue
             | light and once I reduced it the problem dissapeared.
        
               | nsxwolf wrote:
               | This isn't true? Myopia develops rapidly in youth then
               | stabilizes in adulthood. It gets a worse with age, not
               | corrective lenses. Then sometime after 40 you flip to
               | presbyopia when your lenses lose flexibility.
        
               | tartoran wrote:
               | I don't have severe myopia and I'm fine with no glasses
               | for now. The optometrist detected .5 correction needed
               | but advised me to not go for it for the reason I
               | mentioned. I think they are more qualified to give this
               | advice than some rando on the internet. If they were a
               | mercenary they'd tell me to go for it, that optometry
               | practice was part of an eye glasses store and I'm sure
               | they'd gain from my business there. And here I am 20
               | years later not wearing glasses yet. As I'm getting older
               | my vision is getting slightly worse, I'll probably get to
               | wear them at some point but that's beside the point.
        
               | ak217 wrote:
               | There is plenty of information about this in trusted
               | sources, the way you're describing this is incorrect.
               | Overcorrection and badly designed simplistic optics can
               | make myopia worse in childhood when the eye is growing.
               | Your eye is no longer growing.
               | 
               | Don't trust everything your doctor says verbatim, they
               | often oversimplify and their information can be out of
               | date. Give your doctor the benefit of the doubt but check
               | it against other sources and use it to build a mental
               | model.
        
         | amelius wrote:
         | Are you sure you are not also changing total luminance?
        
           | refulgentis wrote:
           | They are, just, don't realize it. Anything off white will be
           | < luminance than white. People replying they _need_ it need
           | to be turning their monitor brightness down.
        
             | Melatonic wrote:
             | Best thing to do is use a scripting app that can make
             | hotkeys for controlling monitor brightness. You can
             | directly control the actual backlight of the monitor and
             | lower it in the evening and at night. Same as pressing the
             | physical button. Great when you have multiple displays
        
         | himata4113 wrote:
         | I actually cannot use my monitor without nightshift, any white
         | page just makes my eyes water, painful even. I had it off for a
         | day when I switched to linux and immediately my eyes started
         | drying out.
         | 
         | Safe to say it works for making your eyes less tired at least.
        
         | nsxwolf wrote:
         | I love Night Shift.
        
         | taeric wrote:
         | I find it somewhat pleasant, but by far the best thing I did to
         | help my eye strain was greatly lower the brightness. Basically,
         | I was told to make it so that my phone's camera could see
         | something on the screen and my desk at the same time without
         | washing out.
         | 
         | After doing that, I have found that the "temperature" of the
         | screen doesn't really matter to me that heavily.
        
           | kpw94 wrote:
           | > Basically, I was told to make it so that my phone's camera
           | could see something on the screen and my desk at the same
           | time without washing out
           | 
           | +1. The low-tech version of this I've heard and I've been
           | doing is:
           | 
           | Hold a printed white paper sheet right next to your monitor,
           | and adjust the amount of brightness in monitor so the monitor
           | matches that sheet.
           | 
           | This of course requires good overall room lightning where the
           | printed paper would be pleasant to read in first place,
           | whether it's daytime or evening/night
        
             | taeric wrote:
             | I think this was what I was told the first time. The
             | advantage of taking a picture with my phone's camera is it
             | kind of made it obvious just how much brighter the screen
             | was then the paper.
             | 
             | Which, fair that it may be obvious to others to just scan
             | their eyes from screen to paper. I've been surprised with
             | how much people will just accept the time their eyes have
             | to adjust to a super bright screen. Almost like it doesn't
             | register with them.
        
             | Marsymars wrote:
             | There's some overlap with bias lighting here - good overall
             | room lighting works if you've got good daylight, but it's
             | much easier to get bright bias lighting at night than to
             | light up the entire room.
        
           | DANmode wrote:
           | Concur that most displays are set 25-50% too bright by
           | default.
        
         | metalliqaz wrote:
         | My Windows 10 PC glitches out most days where the 3rd monitor
         | doesn't properly apply the Night Light setting. So I turn it
         | off and on to fix it. The full blue brightness is awful and
         | definitely harsh on my nighttime eyes. I'm not sure I could
         | believe it's placebo
        
         | refulgentis wrote:
         | It is a placebo, it is an aesthetic thing. It is not something
         | that helps anything at all physically.
         | 
         | This was always well known. It didn't matter 5 years ago, 10
         | years ago, when OS added it. Easier to let it go than argue.
         | 
         | But with HDR, it matters _enormously_ people are well educated
         | on this. Monitors are approximately light bulbs, and we 've
         | gone from staring into a 25W light bulb to a 200W one. (source:
         | color scientist, built Google's color space)
         | 
         | > What is the authors problem lol? It feels a lot better on
         | eyeballs to use warm light things. Why does he care?
         | 
         | I think it's better to avoid stuff like this. Been here 16
         | years and a flippant "whats his problem" "lol" and "why does he
         | care" is 99th percentile disrespectful. It's not about what
         | you're arguing, its just such a fundamental violation of what I
         | perceive as the core tenant of HN, "come with curiosity." You
         | are clearly curious, just, expressing it poorly.
        
           | RupertSalt wrote:
           | username checks out
        
             | refulgentis wrote:
             | Hahaha in my 37 years I don't think anyones mentioned
             | looking it up, cheers. I chose it when I was 8 by flipping
             | open my mom's 2000 page tome of a Merriam Websters, closing
             | my eyes, and putting my finger on the page.
        
           | wtetzner wrote:
           | > It is not something that helps anything at all physically.
           | 
           | That's a pretty strong claim to make.
        
             | refulgentis wrote:
             | It's not a strong claim. It's a settled one. The literature
             | on blue light filters and screen-emitted blue light at
             | display intensities is clear and has been for years, even
             | if approaching it from first principles isn't convincing,
             | or the first principles aren't known.
             | 
             | The thing about color science is that everyone has eyes, so
             | everyone assumes they already have the full picture. One
             | can experience warm light feeling "nicer," and the jump to
             | "this is physically helping me" feels so self-evident that
             | anyone saying otherwise must be the one making a strong
             | claim. But "I prefer the aesthetic" and "this is
             | physiologically beneficial" are two completely different
             | statements, and only one of them survives controlled study.
             | 
             | I don't care if people use night shift. I'm not trying to
             | take anyone's warm tint away. But we are now in an era
             | where consumer displays are pushing luminance levels that
             | are physically, measurably significant - not "I feel like
             | it's bright" significant, but "this is a fundamentally
             | different amount of light entering your eye" significant.
             | Getting the basics right matters now in a way it didn't
             | when we were all staring into dim LCDs and the worst case
             | was people shifting white balance so the color temperature
             | was incandescent, not D65.
        
               | moodyScarf wrote:
               | so whats the takeaway? just turn down the brightness off
               | your monitors? the blue light option of my benq monitor
               | doesnt help?
        
               | refulgentis wrote:
               | Correct - more or less, I love BenQs but haven't had one
               | in a few years. Dunno what _exactly_ _their_ blue light
               | filter does. A software-based nightlight is usually going
               | to turn whites offwhite, i.e. the yellowing you see _is_
               | effectively darkening  / lowering brightness. Its just,
               | its accidentally fixing it and the fix is much less than
               | it would be by directly lowering brightness.
        
         | schiffern wrote:
         | Aggravatingly, you can't set Night Shift to actually be on
         | 24/7. It always has a "seam" where it fades off and then turns
         | back on.
         | 
         | One trick is to schedule this as a bedtime reminder to put down
         | the phone for the night (phone fasting).
        
           | InMice wrote:
           | I kind of despise that part about nightshift, since i almost
           | always like to keep it at medium anytime indoors and during
           | winter. But in the later evening I want it max, and when i
           | got to bed i want it even more. And ive always despised flux
           | for that too. It's even worse since a lot of times i sleep in
           | two phases each night and it doesnt allow to change the
           | length of night time. So dumb.
           | 
           | In a way it's mildly frustrating, but also slightly insane to
           | me that some of these things are so limiting in control. I
           | cant just be given a simple on/off toggle? There is a project
           | manager(s), paid millions collectively that sit in a room and
           | decide "No, you cannot keep nightshift on, it will turn off
           | at 7 AM every morning." Like... WTF.
           | 
           | Stuff like this just keeps on getting worse and worse - and
           | more and more common.
           | 
           | Ive created shortcuts to jump directly to night settings and
           | a shortcut to enable color filters. Still...
        
             | nandomrumber wrote:
             | Can't f.lux be controlled from the command line? I seem to
             | recall it can.
             | 
             | If so, you should be able to cron it to do whatever you
             | want.
             | 
             | I was using redshift on Linux for a while and had some
             | aliases set to trigger various settings.
        
               | InMice wrote:
               | Ive never been aware of that and when I look it's just
               | forum posts of people asking more than once with no
               | reply.
        
               | nandomrumber wrote:
               | I can't quite reach a Mac from where I'm sitting at the
               | minute, maybe someone can try invoking f.lux from the
               | command line.
        
         | MBCook wrote:
         | Is the author arguing anything about eye strain? The word
         | "strain" doesn't even appear on the page.
         | 
         | I think they're purely talking about the idea that cutting back
         | on blue light will help you sleep better. Nothing else.
         | 
         | Why would the author care? Honestly it does seem like one of
         | those junk science things that popped up a couple years ago
         | that all of a sudden was everywhere. I literally remember
         | comments here on hacker news from people saying Apple was
         | killing people because they were blocking F.lux and didn't have
         | night shift yet. Yes they were the most hyperbolic, but they
         | were there.
         | 
         | I kind of like Night Shift too, for similar reasons. But I
         | don't think it ever did anything for my sleep. Nor did I ever
         | expect it to.
        
         | simoncion wrote:
         | > What is the authors problem lol?
         | 
         | I'm not the author, but every time I've seen Night Shift (and
         | things like it) being used, they've done a grand job of royally
         | fucking up the colors of whatever's on screen.
         | 
         | > It feels a lot better on eyeballs to use warm light things.
         | 
         | That's, like, your opinion, man. The lights in my house are all
         | 5000K lights, and I _love_ it.
         | 
         | I expect you'd get _way_ more out of reducing the brightness of
         | your screen [0] than fucking with its colors. _So_ many people
         | seem to love having searingly-bright screens shining into their
         | faces... I don 't get the fascination.
         | 
         | [0] If you've got the monitor's brightness at minimum and it's
         | still too bright, then there are software controls to further
         | reduce it.
        
           | disillusioned wrote:
           | I respect that other people have the right to their opinion,
           | but 5000K lights 24/7 is so completely insane to me. How? How
           | do you get by with "dentist office mall kiosk" lighting
           | blaring every hour of the day?
           | 
           | I have an adaptive Lifx bulb that changes from 5000K during
           | the day and then shifts down to 3000K at night, before
           | tapering down to 2700K for overnight and it's amazing. 5000K
           | in the corner of a dark room is just so disjointed and
           | intense and upsetting to me, if I stay at an Airbnb for more
           | than a night or two and there are daylight bulbs installed,
           | I'll literally buy replacement bulbs and change them out.
        
           | wtetzner wrote:
           | > they've done a grand job of royally fucking up the colors
           | of whatever's on screen.
           | 
           | Pretty sure that's the point?
        
         | tuetuopay wrote:
         | Well he goes on to rant about how it changes the colors
         | displayed by the monitor, so a publisher cannot show the
         | intended color (cyan in the example).
         | 
         | Except he completely ignores that's actually expected for a
         | cyan object to be duller at night: it's the albedo of the
         | object and the perceived color will dramatically changed
         | between daylight and nightlight. So the screen is more
         | _contextually_ correct by toning down cyan, and the colors we
         | perceive will match (and reinforce) the circadian rythm: the
         | user will recognize cyan.
         | 
         | Of course, doing color-sensitive work should not be done with
         | such filters.
        
       | pier25 wrote:
       | > _I took a sample of 4 websites /apps (Google, X, Github, and
       | VSCode) with the SpyderX colorimeter + a diffuser to average over
       | a larger area of the screen, and found reductions in luminance
       | ranging from 92% to 98%! That's huge._
       | 
       | What about TikTok or Youtube?
        
       | SoftTalker wrote:
       | I have my phone in monochrome (i.e. greyscale) mode and just
       | subjectively it's much easier to look at especially at night. I
       | have it at the lowest brightness and it's still very readable.
       | Human eyesight is basically monochrome in low light settings
       | anyway.
        
         | culi wrote:
         | I have an accessibility shortcut to turn my screen greyscale
         | with triple taps but I kept turning it off so I could see the
         | clues on sudoku and now I've forgotten I even had this for
         | almost a year
         | 
         | Low brightness is great though. I didn't realize most of the
         | battery drain on a phone is often just the screen. Lowering the
         | brightness to as little as I need has been great for battery
         | life
        
       | cjbgkagh wrote:
       | I use blue blocking glasses, like Bono but darker and they do
       | work. I also use UV LEDs to help me wake up, which also works.
       | 
       | I agree with the premise that night shift and other color warmth
       | features are insufficient to have a strong effect, though they do
       | help with eye strain which is still a positive.
        
       | harrall wrote:
       | I firmly believe this varies between people significantly.
       | 
       | Blue light filters do not work for me because I fall asleep on
       | command everyday all the time regardless if WW3 is outside.
       | 
       | BUT it also seems the effect of poor sleep seems to be MUCH worse
       | for me than other people. I go from extreme motor coordination to
       | dropping cups in a span of 3 days of poor sleep.
       | 
       | There's a chemical called adenosine which accumulates over the
       | day that induces sleepiness and there are genetic variations that
       | can affect your susceptibility to it. Receptors notice the
       | accumulation of adenosine and use it as a signal to "scale down."
       | 
       | I think that I am more sensitive, explaining my ease of sleep but
       | also the effect of it when it accumulates due to poor sleep
       | (sleep flushes it away). Yeah it's great when I'm in bed but it's
       | not great when I want to throw a ball and my brain wants to be
       | stingy. It basically means that someone else's "helpful guide to
       | sleep" is completely different from my "helpful guide to sleep."
        
         | lowdest wrote:
         | >the effect of poor sleep seems to be MUCH worse for me than
         | other people. I go from extreme motor coordination to dropping
         | cups in a span of 3 days of poor sleep.
         | 
         | Are you sleeping enough? When I was getting too little sleep,
         | averaging 5.5 hours per night, this described me well. A single
         | sleep interruption could make me lose most of a day of work.
         | I'm sleeping better and longer now, and it seems I'm more able
         | to tolerate small interruptions.
        
           | harrall wrote:
           | Yeah I've gotten 8 hours of sleep almost everyday for 15
           | years, ever since I put 2+2 together. In my early 20s, I
           | didn't like being bad at sports and I found sleep was my
           | single most important factor.
           | 
           | Similar to you, I also noticed that if I miss good sleep for
           | several days, it stacks. I treat sleep like a battery. A day
           | uses up 20% and good sleep fills it back up, but only like
           | 30%. One missed night isn't that bad but I also can't recover
           | several nights' worth.
        
       | mikkupikku wrote:
       | Why is it that a few people seem to get bent out of shape by
       | redshift and/or dark modes? If you don't like it, don't use it.
       | Whining about scientific evidence is pointless, even if it all
       | only comes down to user preferences with no science behind it, so
       | what? Let people enjoy things.
        
       | ctbeiser wrote:
       | It seems pretty clear in the OP that headline is misleading--they
       | do work, just not as well as he would like. I think that a 50%
       | cut in light emission is pretty good--and you can stack that with
       | the other interventions listed, like auto-dark mode and reducing
       | light in your room.
        
         | leni536 wrote:
         | Note that it's only 50% if you don't normalise back to absolute
         | brightness.
        
       | nicoburns wrote:
       | Blue light filters definitely work for me. But it needs to be a
       | strong filter (quite a bit stronger than the strongest setting of
       | Apple's built-in filter).
        
         | nomel wrote:
         | Yes, article title is clickbait. Partial filters don't work,
         | but as they suggest, 100% filter of blue light (resulting in no
         | blue light present), DO work.
         | 
         | You can get this with Apple's strongest filter, the color
         | filter, in Settings > Accessibility > Display & Text Size >
         | Color Filters, rather than night shift. Only red sub-pixels are
         | illuminated with it. It can be added to the triple click power
         | button accessibility shortcut.
         | 
         | That's what I use. I have a shortcut set to enable it when I
         | put my AirPods in at night.
        
       | Groxx wrote:
       | So the main claim presented here is that _reducing blue_ reduces
       | total  "light" (lumens? watts?) by 50% (totally believable), and
       | that reduction in light is all that matters for sleep?
       | 
       | That seems reasonable. The pseudoscience wankery that the fad has
       | brought bothers me a lot too.
       | 
       | ... but I'm not sure that's much of an argument against blue
       | light filters, aside from color complaints. That seems to
       | _support_ that it 's Useful and Good and is Achieving Its
       | Intended Goal. It's reducing total luminance, _because people
       | prefer it over reducing screen brightness overall_. I sure as
       | heck do anyway (as night shift modes, they 're a more
       | comprehensive option than dark mode), though I think I'll
       | experiment with just reducing brightness a bit.
       | 
       | ----
       | 
       | For melatonin in particular, fully agreed. The recent trend of
       | "can't even get <5mg in stores, and >10mg is appearing regularly"
       | in the USA is mind-boggling to me. AFAICT it's exclusively
       | because it's a "supplement" and therefore practically
       | unregulated, and these companies don't give a shit about anyone
       | they harm, just profit.
       | 
       | Start with something like https://a.co/d/0dISg7oa (0.3mg, this is
       | what I personally use) and go up from there, slowly.
        
         | SoftTalker wrote:
         | So buy 5mg, and split the tablet in half.
        
           | Groxx wrote:
           | that'd give you 2.5mg, which is still _almost 10x more_ than
           | what I linked.
           | 
           | it's possible to split and separate them enough of course,
           | but beyond "roughly half" it gets rather difficult. I've
           | considered getting the liquid ones and a micro-dropper for
           | smaller doses (if they'd even be small enough, many
           | combinations are not), but 0.3mg pills are rather convenient
           | and worth the small amount of money for me.
        
             | SoftTalker wrote:
             | Oops, missed the decimal position!
        
             | IAmBroom wrote:
             | Some research indicates people over 50 (includes me)
             | achieve best results at 0.3 microgram dosage, which is
             | 1,000 lower(!). Higher dosages reduce the effect.
             | 
             | You might take a quick sec to look into the data. You can
             | buy 5mcg on Amazon, although 5 mg is more common (and 10mg,
             | and ...).
        
               | Groxx wrote:
               | after an initial "... is that a misquote too? sounds
               | super low" I decided to hunt around. I haven't seen
               | anything on _that_ low of a dose... but doing the math,
               | it does seem to make some sense I suppose. a rough check
               | of the total amount of melatonin in your blood at night
               | implies something like 0.5mcg at peak (peak concentration
               | at ~100pg /ml times 5L of blood). lots more is produced
               | in a night because it has a short half-life, but yea,
               | blood concentration is lower than I remembered.
               | 
               | what I _also_ haven 't seen though is anything covering
               | how well it's absorbed through your digestive system.
               | 0.3mcg intravenously I can certainly see being effective,
               | but orally? sublingually? not sure. but you've definitely
               | got me interested in looking more :)
               | 
               | (initial results: https://en.wikipedia.org/wiki/Melatonin
               | _as_a_medication_and_... implies it varies quite a lot,
               | but I'm seeing it centering around 15%-ish many places.
               | so you might want like 3mcg to hit normal levels? and
               | https://pmc.ncbi.nlm.nih.gov/articles/PMC5405617/ is
               | implying 1-5mg -> 10x-100x normal concentration peak, so
               | that does hit the right ballpark reasonably well... I
               | guess I'm going to start experimenting with even smaller
               | doses!)
               | 
               | I'm not finding any 5mcg on amazon tbh. Likely in no
               | small part because its search is trash nowadays. Mind
               | sharing a link?
        
             | dinkelberg wrote:
             | Melatonin pills seem to have extremely bad quality control:
             | 
             | "Melatonin content varied from an egregious -83% to +478%
             | of labeled melatonin and 70% had melatonin concentration <=
             | 10% of what was claimed. Worse yet, the content of
             | melatonin between lots of the same product varied by as
             | much as 465%.
             | 
             | [...]
             | 
             | The last disturbing finding was more than a quarter of
             | melatonin products contained serotonin, some at potentially
             | significant doses."
             | 
             | https://pmc.ncbi.nlm.nih.gov/articles/PMC5263069/
             | 
             | "In products that contained melatonin, the actual quantity
             | of melatonin ranged from 74% to 347% of the labeled
             | quantity. Twenty-two of 25 products (88%) were inaccurately
             | labeled, and only 3 products (12%) contained a quantity of
             | melatonin that was within +-10% of the declared quantity.
             | [...] Serotonin was not detected in any product."
             | 
             | https://jamanetwork.com/journals/jama/fullarticle/2804077
             | 
             | "Half of the products tested met the label's claim for
             | melatonin, which means they fell between 76 and 126 percent
             | of the claimed amount. Of the products tested, 20 had
             | between 0 and 76 percent of the labeled content, and 35 had
             | between 126 and 667 percent."
             | 
             | https://www.washingtonpost.com/wellness/2025/06/25/melatoni
             | n...
        
               | dragonwriter wrote:
               | > Melatonin pills seem to have extremely bad quality
               | control:
               | 
               | Melatonin is treated as a dietary supplement in the US
               | rather than a drug, and this seems to be a widespread
               | problem with supplements, given the incredibly lax
               | regulatory regime.
        
               | dinkelberg wrote:
               | One more relevant study, but on the health effects of
               | long term melatonin use:
               | 
               | https://newsroom.heart.org/news/long-term-use-of-
               | melatonin-s...
               | 
               | "The main analysis found:
               | 
               | * Among adults with insomnia, those whose electronic
               | health records indicated long-term melatonin use (12
               | months or more) had about a 90% higher chance of incident
               | heart failure over 5 years compared with matched non-
               | users (4.6% vs. 2.7%, respectively). * There was a
               | similar result (82% higher) when researchers analyzed
               | people who had at least 2 melatonin prescriptions filled
               | at least 90 days apart. (Melatonin is only available by
               | prescription in the United Kingdom.)
               | 
               | A secondary analysis found:
               | 
               | * Participants taking melatonin were nearly 3.5 times as
               | likely to be hospitalized for heart failure when compared
               | to those not taking melatonin (19.0% vs. 6.6%,
               | respectively). * Participants in the melatonin group were
               | nearly twice as likely to die from any cause than those
               | in the non-melatonin group (7.8% vs. 4.3%, respectively)
               | over the 5-year period."
               | 
               | However they were not able to control for severity of the
               | insomnia and used dosage, because that data weren't in
               | the dataset.
        
               | Groxx wrote:
               | I really wish they'd name-and-shame the brands. I don't
               | see how hiding it helps encourage better behavior. If
               | anything, it seems like they should be publishing legal
               | ranges, and rewarding testing labs that catch things
               | outside it by fining failures.
        
         | gowld wrote:
         | No, in the OP (after an unclear intro that confuseed many
         | readers), there is a graph that shows blue wavelength intensity
         | is important, but software light filters don't filter a lot of
         | it, and the effect is cancelled by increasing overall
         | brightness.
        
           | Groxx wrote:
           | If software filters are reducing _total_ light by 50% while
           | only affecting blue-ish tones, and that 's a total light
           | level comparable to _multiple_ brightness steps on a Mac...
           | tbh I think it 's reducing it quite a lot. Many I see using
           | them (myself included) don't tweak brightness when enabling
           | it, and many (all?) systems don't adjust their brightness to
           | match the perceived change from a software filter (on my
           | Linux machines in particular I have never seen this happen,
           | don't know about Macs though).
           | 
           | Half is not a lot, sure, but their ultimate suggestion is to
           | do the same ~half change:
           | 
           | > _You can decrease the amount of light coming from your
           | screen by more than half simply by dimming the screen by
           | several notches._
           | 
           | which is definitely significantly more than I see people
           | doing voluntarily in the hundreds of millions.
           | 
           | Do they have any evidence that people are raising system
           | brightness to match the 50% loss from the filter? If not, it
           | still seems like a rather significant mark in their favor.
           | Perhaps not _sufficient_ to meet the goals (they seem to be
           | recommending a larger change, but aren 't specific), but I
           | see no claim that a lesser decrease in light is _worse_.
           | 
           | ---
           | 
           | Late edit: on second thought... let's go through this more
           | rigorously. For both myself and any other readers, because I
           | want to make sure I'm following it accurately too.
           | 
           | The main explicit points in this article are, in order:
           | 
           | - night shift does not help with sleep (the main claim)
           | 
           | - blue light is not special, in particular because the
           | "[most] sensitive to blue" research is mis-quoted to mean
           | "blue is bad", but it's actually sensitive to blue and green
           | (seems very well supported)
           | 
           | - night shift reduces blue and green by about half (tested
           | themselves)
           | 
           | - half of absolute is not a lot because vision and a lot of
           | the related biology is logarithmic (100% agreed)
           | 
           | - halving light affects 25%-50% of melatonin levels (linked
           | research)
           | 
           | - many people use Night Shift (100% agreed, and they have
           | decent data to back it up)
           | 
           | - dark mode is better than night shift (>90% vs ~50%, implied
           | leaning on the linked research earlier. agreed, seems
           | straightforward)
           | 
           | - dimming your screen by several steps is the same or better
           | than night shift (as it decreases brightness more, same
           | reasoning as dark mode. agreed.)
           | 
           | That still sounds rather in favor of Night Shift. It's
           | targeting the correct color range (NOT the pseudoscience
           | blathering of just blue blue blue), it has a moderate affect
           | on melatonin levels at the light level changes it creates,
           | and it's used by a huge amount of the population.
           | 
           | Nowhere in there that I can see is anything to back up "Night
           | Shift does not work". Only "it seems to be doing things
           | right, it just isn't quite enough on its own" and "ARGH it's
           | not just blue light STOP PROMOTING FAD PSEUDOSCIENCE". That
           | seems... fine? Most things are not silver bullets.
        
       | ltbarcly3 wrote:
       | Well they work in that the color temperature of the light in my
       | house is much cooler during the day than at night, and it's nice
       | to match it so it doesn't look jarring.
        
       | pclowes wrote:
       | You can just do things. Not everything needs a study, you don't
       | have to justify yourself to anyone!
       | 
       | Try things, if you like them, do them!
       | 
       | Try not living a neurotic "study" based life, I am trying it and
       | its pretty great!
        
         | Barbing wrote:
         | (just nothing from Goop)
        
         | tartoran wrote:
         | Absolutely and this is something that can be tested rather
         | easily. If blue filters aren't immediately helpful to eye
         | strain then they probably don't work for you but if they are
         | they probably do work for you.
        
           | IAmBroom wrote:
           | You can test the negative easily, but the positive is harder.
           | Thus: placebos.
        
             | tartoran wrote:
             | You're saying that my eyes straining going away from
             | reduced blue light is placebo? I can feel it right away and
             | it gets worse in minutes, time and time again. As soon as I
             | remove blue light the strain is gone. Honestly, I don't
             | care what other people have to say, to me it's obvious that
             | it helps and I stick to it. Again, I don't think this is
             | universal and it may not help you if you don't notice
             | immediate improvement.
        
             | cgriswald wrote:
             | On the level of the individual a working placebo is a
             | success.
        
           | Perizors wrote:
           | Every dismissive reply talks about eye strain nada that is by
           | far not what the author is taking about.
        
         | IAmBroom wrote:
         | I am aware that meta-studies of glucosamine chondroitin show No
         | Significant Gains in joint pain. I would never waste my money
         | on it.
         | 
         | But my newly adopted dog had hip issues, and I bought a few
         | months worth of a diet supplement in the hopes of doing
         | something meaningf... dammit, it's glucosamine.
         | 
         | They claimed double-blind studies showed decreases in limping
         | in just two months.
         | 
         | Two months, more or less, I stopped seeing him limp by the time
         | we left the dog park. He still does sometimes, but it's rare -
         | not every damn day, by any means.
         | 
         | We aren't that fricking different biologically from dogs in our
         | skeletal attachment system. Maybe it's still a placebo, but it
         | seems to defeat that idea. Maybe enough human issues are based
         | on things that don't translate to dogs - sitting at a desk all
         | day, eating junk food, walking upright... - that it helps them,
         | but not enough of us.
         | 
         | Don't know. These GC supplements have convinced me it's worth
         | my money, and he loves eating them, so he votes 'yes', too.
        
           | rkomorn wrote:
           | I found it interesting that placebo effect is also sort of
           | relevant in pet care: it makes owners believe the pet is
           | doing better.
           | 
           | Unfortunately, the study that showed this used the same
           | medicine my dog had been on, and since it was for epilepsy, I
           | can totally believe that whether I thought it worked had no
           | connection to its effectiveness.
        
         | root_axis wrote:
         | Neurotic is bad by definition, but using studies to inform your
         | habits seems like a wise thing to do.
         | 
         | Obviously you shouldn't follow studies blindly, especially
         | because many studies are poorly conducted and do not replicate,
         | but in general, we know that just following your gut is
         | suboptimal and sometimes dangerous in cases when studies give
         | us clear information.
        
           | wtetzner wrote:
           | Unfortunately it doesn't seem to be easy to understand what
           | studies are actually demonstrating, based on how often you
           | see people making giant leaps to conclusions that don't
           | really follow from study results.
        
         | stuckonempty wrote:
         | You can and should! Just don't go justifying that your choices
         | are rooted in science when they aren't.
        
           | thrawa8387336 wrote:
           | What, you think Newton relied on a study to believe his own
           | conclusions?
        
         | UqWBcuFx6NV4r wrote:
         | Yep. This attitude is utterly pervasive. We may as well just
         | give up and start saying "science says...", the way some
         | people, especially some people _here_ , seem to misunderstand
         | what role studies play, what their limitations are, etc.
         | 
         | Imagine if you have a rare genetic mutation that causes Night
         | Shift to be extremely, extremely effective, and you don't even
         | try to use it because A Study Didn't Tell You To.
         | 
         | You are indeed allowed to just...try things and see for
         | yourself, especially such ostensibly low-risk things like this.
         | The literature is not a bible.
        
       | pie_flavor wrote:
       | If you aren't aware, your phone's screen can go much dimmer than
       | the minimum brightness offered by the slider, if it supports HDR.
       | There are apps that use an HDR screen overlay to lower brightness
       | all the way down to the dimmest you can perceive. In my own
       | experience, 'half' the brightness of 'minimum' brightness is
       | plenty dark enough to not disturb sleeping at all if using my
       | phone in bed.
        
         | Barbing wrote:
         | Also for third-party monitors with MacBooks: BetterDisplay
         | 
         | Can even use an external keyboard's native brightness buttons.
         | Can still use f.lux if desired too though Night Shift maybe
         | Sherlocked there a bit...
        
       | lisper wrote:
       | Night shift seems to have a very strong causal effect on my sleep
       | cycles. Up until about ten years ago I was a night owl, rarely
       | falling asleep before midnight and rarely waking up before 8.
       | Then I started getting serious about light hygiene and using
       | night shift and now I'm a serious day person, rarely staying
       | awake after 11 and rarely waking up after 7. But the real
       | clincher is that when I travel I don't change the time zone on my
       | computer (because it screws up my calendar). But my sleep cycle
       | continues to track my home time zone for a very long time. I life
       | in California, but at the moment I'm in Hawaii. I've been here
       | three weeks so far. At home I'd fall asleep around 11 and wake up
       | around 7, but here I'm getting sleepy at 9 and waking up at 5.
       | 
       | My wife, on the other hand, is a hard-core night owl even with
       | night shift. So apparently there is a lot of individual
       | variation.
       | 
       | This article has inspired me to do a control experiment by
       | switching night shift off. Check back here in a week or so for
       | the results.
        
         | Barbing wrote:
         | >inspired me to do a control experiment
         | 
         | Delightful, see ya the 27th!
        
         | gowld wrote:
         | > Night shift seems to have a very strong causal effect on my
         | sleep cycles.
         | 
         | > light hygiene and using night shift
         | 
         | The OP article is primarily about separating the variables you
         | lumped together.
        
         | nandomrumber wrote:
         | > _light hygiene_
         | 
         | Awesome, hadn't come across this term before.
         | 
         | You might appreciate the concept of _chronotypes_.
         | 
         | https://en.wikipedia.org/wiki/Chronotype
         | 
         | The DOAC podcast recently hosted Dr. Michael Breus on same.
         | 
         | Apple Podcast link, or conjure your own:
         | 
         | https://podcasts.apple.com/au/podcast/the-diary-of-a-ceo-wit...
        
           | Perizors wrote:
           | Bear in mind that chronotypes, as stated in the wiki, only
           | varies about 2-3 hours from each other. This is just to say
           | that there is no nocturnal person in terms of biology, we are
           | all diurnal mammals after all.
        
             | nandomrumber wrote:
             | Yeah, like anything, proponents like the guy in the podcast
             | I referenced probably overhype the importance / impact.
        
         | lotu wrote:
         | I remember when I found Flux (third party predecessor to night
         | shift) sometime in 2013. It worked in a week, I'd been staying
         | up until 3am for most of the year and a started going to bed at
         | midnight.
        
       | crazygringo wrote:
       | These are the kinds of articles that give science a bad name, and
       | that make people anti-science.
       | 
       | You might as well try to claim hot tea doesn't help you get to
       | sleep, or reading before bed doesn't, or whatever else you do to
       | wind down.
       | 
       | I personally don't care if some narrow hypothesis about blue
       | light and melanopsin is false. I know that low, warm, amber-
       | tinted light in the evening slows me down in a way that low,
       | cold, blue-tinted light does not. That's why I use different,
       | warmer lamps at night with dimmers, and keep my devices on Night
       | Shift _and_ lower brightness. It works for me, and seems to mimic
       | the lighting conditions we evolved with -- strong blue light
       | around noon, weaker warmer light at sunset, weakest warmest light
       | from the fire until we go to sleep. Maybe it doesn 't work for
       | everybody. That's fine. But it certainly does for me.
       | 
       | And maybe it's not modulated by melanopsin. Or maybe it's not
       | about blue light, but rather the overall correlated color
       | temperature (CCT), e.g. 2100K instead of 5700K. Who knows.
       | 
       | But this type of article is bad science writing. It shows why
       | _one hypothesis_ as to why a warmer color temperature would
       | result in _one other physiological change_ isn 't supported. That
       | doesn't mean "blue light filters don't work" as a universal
       | statement. It's hubris on the part of the author to assume that
       | this _one_ hypothesis is the _only potential mechanism_ by which
       | warmer light might help with sleep.
       | 
       | And it's this kind of science writing that turns people off to
       | science. I know, through lots of trial and error and
       | experimentation, that warm light helps me fall asleep. And here
       | comes some "AI researcher and neurotechnologist" trying to tell
       | me I'm wrong? He says it's "aggravating" that people are
       | "actually using Night Shift". I say it's aggravating when people
       | like him make the elemental mistake that showing _one_ biological
       | mechanism doesn 't have an effect, means _no other_ mechanisms
       | can either.
        
         | AshamedCaptain wrote:
         | > These are the kinds of articles that give science a bad name,
         | and that make people anti-science.
         | 
         | No, it is attitude like yours that brings humanity a bad name.
         | 
         | "Blue light effects" have always had highly questionable
         | evidence behind it, what has been sold and marketed under the
         | guise of it has had _zero_ evidence behind it. But now that you
         | are reminded that it is actually bullshit, you react with
         | skepticism.
         | 
         | "Feels good to me" is hardly evidence to begin with. It's
         | something that is even more flimsy than sociology. I have my
         | doubts it should even be called medicine.
         | 
         | You have to remember that a shitton of people day after day
         | "show" "evidence" that homeopathy works. Even though it has no
         | plausible mechanism of action. So clear mechanism of action is
         | about as important as the evidence itself. (see Science-based
         | medicine)
         | 
         | I could understand (not justify) skepticism in many cases (such
         | as "common wisdom" from 1000 years ago) but this particular
         | topic should have raised your skepticism 20 years ago back when
         | the craze/marketing stunt was starting, and not now.
        
           | chuckadams wrote:
           | Someone says that other psychological factors (which have
           | physical effects) help them sleep and they "bring humanity a
           | bad name"?
           | 
           | Maybe think on that a little bit.
        
             | AshamedCaptain wrote:
             | No, he said "this gives science a bad name"/"makes people
             | anti-science" because some article published something that
             | contradicts his anecdote of how well he thinks he sleeps.
             | That gives humanity a bad name. And your direct insults do,
             | too (which fortunately have been edited out).
        
               | chuckadams wrote:
               | The direct insult where I said "touch some fucking
               | grass"?
               | 
               | I certainly stand by it now.
        
               | IAmBroom wrote:
               | Why? You're proud of your insults?
        
           | crazygringo wrote:
           | > _" Feels good to me" is hardly evidence to begin with_
           | 
           | Where did I say anything like that? Please don't
           | mischaracterize my comment, that's not helpful. It's not that
           | it "feels good", it's that it helps at least some people fall
           | asleep more easily, and I know this from personal experience.
           | And many, many other people have written that it does the
           | same for them.
           | 
           | > _" Blue light effects" have always had highly questionable
           | evidence behind it... But now that you are reminded that it
           | is actually bullshit_
           | 
           | You're right that the evidence _for_ it is questionable. But
           | you know what else there 's no conclusive evidence for? That
           | hot herbal tea helps you fall asleep. Or soothing music. Or
           | bedtime stories. Because the funding usually isn't there to
           | perform the kind of large-scale studies required to establish
           | these things, because it's just not a priority or even a good
           | use of our dollars. And lack of evidence for, is not the same
           | as evidence against.
           | 
           | My point is, nothing in this article _does_ establish that it
           | is  "actually bullshit". That's a _gross_ misreading of the
           | science, and that 's what I'm criticizing the article over.
           | 
           | People experiment with things and discover what works and
           | what doesn't. Again, nobody's going around complaining that
           | there's no scientific evidence lullabyes don't help put you
           | to sleep. And neither lullabyes, nor turning your lights down
           | to amber, have anything to do with homeopathy. You can't
           | possibly suggest they're doing _harm_. People aren 't using
           | amber lighting at night _instead of getting their cancer
           | treated_.
           | 
           | But for some reason, low amber lighting to help with sleep
           | makes you and the article author upset? Why? Why does that
           | make you upset, but not hot tea or lullabyes? Or do those
           | make you upset too?
        
             | AshamedCaptain wrote:
             | "feels good to me" and "helps me sleep more easily" are
             | about the same thing: flimsy and almost non-quantifiable
             | personal experiences. About the same level with "I dream of
             | nicer things".
             | 
             | > And many, many other people have written that it does the
             | same for them.
             | 
             | So people write for homeopathy. Homepathy actually is the
             | precursor for using this type of "evidence" for development
             | and study of new "drugs" (hint: this evidence ends up going
             | nowhere useful, quickly).
             | 
             | > Or soothing music. Or bedtime stories. Because the
             | funding usually isn't there to perform the kind of large-
             | scale studies required to establish these things, because
             | it's just not a priority or even a good use of our dollars.
             | 
             | Oh, there is. There are way more studies about this than
             | you can possibly think of. There are medical journals
             | reporting clinical experiences about this daily. You are
             | saying this on an article about study about one of these,
             | ironically enough.
             | 
             | > And lack of evidence for, is not the same as evidence
             | against.
             | 
             | https://en.wikipedia.org/wiki/Russell%27s_teapot
             | 
             | > My point is, nothing in this article does establish that
             | it is "actually bullshit".
             | 
             | Why not?
             | 
             | > But for some reason, low amber lighting to help with
             | sleep makes you and the article author upset? Why? Why does
             | that make you upset, but not hot tea or lullabyes? Or do
             | those make you upset too?
             | 
             | You are the one who suddenly claims this makes people
             | "anti-science", when this particular bullshit is not even
             | 20 years old, and it was already known to be suspect 20
             | years ago. It is just ridiculous that it is now suddenly
             | such a core belief of your persona that even being reminded
             | that it is most likely bullshit is going to drive you to
             | reject science outright.
             | 
             | As I said, I could at least _understand_ (but not justify)
             | much older claims, such as ancient chinese practices or
             | whatever. This makes they make me upset indeed (this is
             | pseudoscience, after all), but what makes me even more
             | upset is the creation of new pseudo-scientific or even
             | anti-scientific "popular wisdom" _in this age_.
        
               | crazygringo wrote:
               | I think you have not actually understood what I wrote,
               | because of this part:
               | 
               | >> _My point is, nothing in this article does establish
               | that it is "actually bullshit"._
               | 
               | > _Why not?_
               | 
               | I've already said it multiple times. Allow me to repeat
               | myself:
               | 
               | > _make the elemental mistake that showing one biological
               | mechanism doesn 't have an effect, means no other
               | mechanisms can either._
               | 
               | You've written a lot, but you haven't understood that
               | this is the core mistake of the article, and the core
               | mistake of what you're trying to argue.
               | 
               | You reply with a reference to Russell's teapot, and that
               | would be fine if you were merely trying to make the point
               | that the effect of amber light on sleep has not been
               | sufficiently proven. But _you 're_ the one literally
               | calling it "bullshit", i.e. _dis_ proven. That's wrong.
               | There's no high-quality study conclusively demonstrating
               | it _doesn 't_ have an effect.
        
               | AshamedCaptain wrote:
               | Certainly you can claim that because not all mechanisms
               | have been disproven yet, then there could still be an
               | effect. That is why I quote Russell's teapot. Your claims
               | are technically not disproven, and may not even be
               | possible to disprove, but that doesn't mean that the
               | existence of the teapot is (most definitely) bullshit.
               | This is what the example of Russell's teapot is trying to
               | show.
               | 
               | I also keep continuously putting the example of
               | homeopathy because it is exactly the same. Homeopathy has
               | plenty of (weak) evidence, but no known mechanism of
               | action. All the proposed religious, memory of water, etc.
               | have been disproved. Certainly you can argue that
               | homeopathy could still be a thing because there could be
               | some physical/biological mechanism that has not yet been
               | disproved! But this is just nitpicking: homeopathy is
               | still bullshit. In the same way that a teapot in space is
               | bullshit.
               | 
               | Anything else is a (useless) nitpick.
               | 
               | In any case, even from day #1 it's been known that blue
               | light could possibly have a mechanism, but there's always
               | been a big stretch from there to claiming that blue light
               | filters/night shift have an effect, and the evidence for
               | the latter is substantially lacking.
               | https://sciencebasedmedicine.org/blue-light/
        
               | crazygringo wrote:
               | I'm sorry, but using the idea of Russell's teapot to
               | claim anything without rock-solid proof is "bullshit" is
               | a deep misunderstanding of the idea. It's wrong, it's
               | offensive, and it's not helpful to genuine understanding.
               | 
               | Amber light is not Russell's teapot. There's widespread
               | anecdotal reporting that it helps with sleep. It's not
               | something nonsensical like a teapot between Earth and
               | Mars. And for you to suggest that they're the equivalent
               | is, frankly, arguing in bad faith.
               | 
               | The world of knowledge is not divided, black-and-white,
               | between things that are scientifically proven and
               | "bullshit". Probably the vast majority of practical facts
               | we rely on daily are not "proven" with empirical studies.
               | That doesn't make them "bullshit". I hope you can
               | understand that.
        
               | AshamedCaptain wrote:
               | No, I do not understand why I cannot call homeopathy
               | bullshit. There's plenty of widespread positive anecdote
               | for it, too!
               | 
               | Why would you think calling one bullshit is "offensive"
               | and not the other? You realize that this "gray" scale
               | that you claim is as unscientific as it gets, right?
               | After all, it worked for me! And I hear that it works for
               | my friends! How can homeopathy/blue light
               | filters/whatever-ritual-you-like-today not work? How can
               | there not be a teapot on the sky?
               | 
               | If the problem is with the word "bullshit", call it
               | pseudo-scientific, but it is almost the same thing.
               | 
               | Tomorrow there could be some evidence of an effect shown
               | in the opposite direction (e.g. blue light filters
               | _harming_ sleep quality*, or performance the day after,
               | or whatever) and you would be as skeptical as with claims
               | of no effect, if not more. See the recent article of
               | white noise in HN and how it was met in the comments.
               | 
               | * Because of people (or worse, software) turning their
               | screens' brightness up to compensate, which I already
               | read an article about long time ago...
        
         | anonymars wrote:
         | > But this type of article is bad science writing. It shows why
         | one hypothesis as to why a warmer color temperature would
         | result in one other physiological change isn't supported
         | 
         | I don't know if I'd even give them that credit (emphasis mine):
         | 
         | > Halving the luminance, at best (around 20 lux baseline)
         | _might get you from 50% to 25% melatonin suppression._
        
         | orbital-decay wrote:
         | What if these filters also cure cancer by some mechanism that
         | isn't known yet? Who knows, it might be true! After long
         | experimentation with warmer lighting my cancer is gone, so it
         | definitely worked for me.
         | 
         | What you're saying is not science either. The entire _medical_
         | usage of blue light filters hinges on just a few papers. If you
         | really can prove those studies inapplicable you can prove that
         | there 's no objective reason to use them (I'm not necessarily
         | saying the author did that).
         | 
         | Whether these filters feel nice is entirely unrelated question,
         | nobody stops you from decorating your living space as you see
         | fit.
        
       | wa008 wrote:
       | Based on my experience, most health benefits are from personal
       | habits over external hardware. But people care health so much,
       | it's a great opportunity for merchants to get revenue.
        
       | alejohausner wrote:
       | I bought some amber glasses from blublocker.com[1], because they
       | link to a research paper that actually measured how much of each
       | wavelength their filters allow (as well as other brands). They're
       | pretty dark, so you have to crank up the brightness on your
       | screen, but I'm confident that I'm not getting ANY blue.
       | 
       | 1: https://www.blublocker.com/blogs/news/what-blue-light-
       | blocki...
        
         | kb9alpp wrote:
         | Nice. The article also mentions BluTech lenses (BluTech LLC,
         | Alpharetta, GA). I've found the marginal utility of bluelight
         | blocking solutions are very context specific, indeed. And
         | mostly-completely bahokie garbage, sadly, but not when it's
         | BluTech and BluBlocker. BluTech/BluBlocker for the screen-
         | induced fatigue is the correct solution. I always get BluTech
         | HI Indoor AR pucks for my prescription lenses. And just switch
         | to prescription sunglasses when I go outside.
        
         | stuckonempty wrote:
         | Those glasses state that they are the only pair that "blocked
         | 100% of harmful blue light in the 400-450 range"
         | 
         | But melanopsin contained in the cells that regulate circadian
         | rhythms have an absorption spectrum extends to slightly beyond
         | 540 nm (see the OP's post). As the author says, "It's not
         | sensitive to blue, it's sensitive to cyan (and blue and
         | green)."
         | 
         | Those glasses probably do what they say in terms of wavelengths
         | they filter, but they are only partially filtering out light
         | relevant for circadian rhythm regulation and sleep.
        
       | cptskippy wrote:
       | I have Night Light perpetually on with all of my devices because
       | I find it softens everything and makes viewing displays less
       | harsh, less garish, less vivid, and less intense. I don't need
       | eye searing HDR constantly cooking my retinas.
        
       | yathern wrote:
       | > Unless your strategy is to create a photo-lab-like screen in
       | pure black and red, or wear deep-red-tinted glasses, it's
       | unlikely that a pure colorshift strategy will cut out that big of
       | a chunk of the spectrum.
       | 
       | I absolutely think this is the right approach. The glasses which
       | do 'blue light filtering' which barely change your perception are
       | clearly placebo, but a very strong redshift I think is obviously
       | a different creature.
        
         | EA-3167 wrote:
         | Absolutely, although dark orange seems to work well enough. If
         | you can put them on and still tell the difference between most
         | colors, they aren't working. I use my pair for one purpose:
         | reading in bed with a backlit e-reader. I can't imagine trying
         | to do much else with them on, they have plastic wings to block
         | light from the side and they're not light.
         | 
         | But they work.
        
         | hinkley wrote:
         | I have a red flashlight I use at night to read books. It's
         | weird after an hour I don't really see it as red anymore, just
         | dim off white.
        
       | zcw100 wrote:
       | I replaced all the light switches in my house with smart dimmers
       | and have the lights dim in the evening. It happens in steps so
       | it's noticeable and it's like a clock ticking down. I don't know
       | if there's anything scientific about it but it's pleasant, like
       | the house is going to sleep so maybe I should too.
        
         | nandomrumber wrote:
         | I like to use the yellow anti-insect lights for the external
         | lighting around my house as they tend to attract way fewer
         | flying insects and fewer spiders as a result.
         | 
         | I also like them in lamps inside for illumination during the
         | evening, with the added benefit of not requiring more IoT
         | devices.
        
         | Marsymars wrote:
         | This is especially nice if you use bulbs that get warmer as
         | they dim. (See the Kruithof curve.)
        
       | TACIXAT wrote:
       | I have had success with an extremely aggressive red filter. My
       | unchecked sleep schedule has me going to bed around 4 am,
       | consistent over decades. I don't consume caffeine or any other
       | stimulant. In the last 4 months I switched my lights to LED bulbs
       | to turn red at 6pm and use QRedshift on Linux (Mint) with the
       | temperature set to 1000k at 6pm. I have consistently been falling
       | asleep around midnight. What is remarkable to me is that I am
       | actually feeling tired at night.
        
       | jrm4 wrote:
       | It's funny, I'm _so comfortable_ calling this guy an idiot purely
       | based on the fact that I 've taken up Bob Ross style painting in
       | like the last 2 years.
       | 
       | Teaches you to pay attention to "objective" colors. And at night,
       | guess what, the colors get more red and less blue. I don't have
       | to pull out as much blue paint for the night scenes.
       | 
       | It would be utterly naive to not thing that there's -- perhaps
       | purely "psychological" (not sure if that's the exact concept but
       | hey) effect by making the "white" on your screen, look like like
       | the "white" you will definitely see in real life, which is going
       | to be orange-r.
        
       | iainctduncan wrote:
       | Regardless of the sleep effect (or lack of) they absolutely do
       | work for reducing eye strain for migraineurs.
       | 
       | It's noticeable to me all the time, but if I'm borderline
       | migraining, or recovering from a migraine, the difference between
       | shifted and not is something I can feel instantly. Shifting all
       | the way over enables me to eek out some work after a migraine
       | without it flaring back up again.
        
       | Waterluvian wrote:
       | I really don't care if they "work" or not. I find it incredibly
       | cozy to have a warmer, calmer screen in the evening.
        
       | reenorap wrote:
       | The entire blue light madness is based on a poor study where N
       | was around 8. And the difference in sleep was something like 15
       | mins. The entire study was based on crap but somehow the entire
       | world has run rampant on the idea that blue light has this
       | profound effect. It just goes to show that bad science is easily
       | propagated, even when there's even more sources of information.
        
         | Marsymars wrote:
         | I don't know enough to defend the study, but I don't think 15
         | minutes of sleep is insignificant. If I'm consistently woken up
         | 15 minutes before my normal wake time it's going to have a
         | negative effect on me.
        
       | baud9600 wrote:
       | I added the "Noir" extension to mobile Safari, now I
       | automatically get dark mode on all websites including Hacker
       | News.
        
         | hinkley wrote:
         | I'm surprised by how may don't have a dark mode though. I
         | decided to do it for my blog despite not really using it
         | myself, and ended up sticking with it on. Still getting blasted
         | in the face by eggshell white everywhere I click.
        
         | the_pwner224 wrote:
         | "Dark Reader" does the same thing on desktop
         | Firefox/Chrome/etc. (& mobile Firefox, maybe also available on
         | mobile Safari?).
        
           | baud9600 wrote:
           | Mobile Safari only does this for sites that implement dark
           | themes (and when you have dark mode enabled in iOS). But many
           | sites don't have these themes. The Noir extension seems to
           | fix the problem for now. There is a reader mode that can go
           | dark but it's manual, per article
        
             | the_pwner224 wrote:
             | I see. Not a Safari user myself. On Firefox & Chrome Dark
             | Reader can force its own dark theme even if the site
             | doesn't provide one. Like Noir does on mobile Safari.
        
       | james_marks wrote:
       | I have a triple-click shortcut in iOS to use the accessibility
       | features to go below the min dim settings.
       | 
       | Otherwise even dark mode is way too bright in a dark room.
        
       | hn_throwaway_99 wrote:
       | I found the basic premise of this blog post to be incredibly
       | flawed. The author seems very sure of himself that blue light
       | filters don't work, but making arguments related to cell types
       | and emissions spectra and circadian rhythms is not the way to
       | make a conclusive argument in a topic like this. Science is
       | _littered_ with recommendations about things that  "plausibly"
       | made sense, but that turned out to be flawed or just absolutely
       | wrong when actually put to a real, scientific test. One example
       | most people are familiar with: the recommendation against eating
       | eggs in the 90s was based on the fact that eggs have a lot of
       | cholesterol, and we knew high LDL levels in blood were associated
       | with a greater risk of vascular and heart problems. So,
       | "logically", it seemed that limiting dietary cholesterol would
       | reduce heart disease. Except when scientists actually tested
       | those recommendations, they turned out to be largely wrong - when
       | you eat a lot of cholesterol, for most people their body's
       | natural production of cholesterol goes down, so unless you're in
       | the small subset of people who are particularly sensitive to
       | dietary cholesterol, eating eggs is fine.
       | 
       | Making recommendations based solely on a theoretical mechanism of
       | action is bad science. The only way to actually test this is with
       | a study that looks at different types of light restriction and
       | its effect on sleep. Obviously it's kind of impossible to do a
       | blinded study for blue light filters, but you could get close by
       | testing various permutations of light changes (e.g. total
       | luminescence, eliminating only very specific wavelengths, etc.)
       | 
       | As another commenter said, it may be a placebo effect, but if it
       | is, who cares? All I care about is that I get a better night
       | sleep, and as someone (unusual among programmers I know) who
       | really doesn't like dark mode, a screen reddener greatly helps me
       | at bedtime.
        
         | galangalalgol wrote:
         | His argument seems to be that the night modes don't remove much
         | blue. My initial assumption was that it was about physical
         | filters. Yellow or amber 99%+ safety lenses are a thing and
         | several of my coworkers wear them. Looking through them at
         | those painfully bright blue leds makes them appear to be off.
         | Yes everything looks strange, but they work. Likewise a
         | different coworker manually removes all blue in the monitor
         | settings themselves independent of the brightness setting. That
         | also works. The author's assertion should be qualified amd
         | narrowed a bit.
        
           | UlisesAC4 wrote:
           | I can absolutely confirm that night mode works wonders. Since
           | ten years ago I discovered them I no longer have dry eye like
           | problems.
        
             | stuckonempty wrote:
             | This is great it works for you but hopefully you realize
             | the weakness of anecdotal evidence when it comes to
             | declaring something is universally effective.
             | 
             | Your n of 1 argument is the equivalent of "my grandpa
             | smoked until he was 95 so smoking clearly can't be bad for
             | your health".
        
               | red75prime wrote:
               | It's more like, "Some people have something going on that
               | ameliorates the cardiovascular and cancer problems caused
               | by smoking."
        
               | whateverboat wrote:
               | I love redshift as well. I actually keep it 24x7, and my
               | eyes don't get tired at all even after 12 hours of
               | programming. Nowadays, turning off redshift feels like an
               | attack on the eyes.
               | 
               | And no, reducing brightness on monitors doesn't have the
               | same effect. I recently upgraded my monitors to 600nits
               | brightness from 350nits and there has been no change in
               | comfort level with redshift but without the redshift, the
               | old monitors (and the new) stil feel very hostile to
               | eyes.
        
               | hn_throwaway_99 wrote:
               | You're right, it's not valid to make any broader
               | conclusions from an anecdote. But it's about just as
               | valid as the author making conclusions based solely on
               | physical "this is what I should expect to happen"
               | hypotheses.
               | 
               | More importantly, as an individual, the only thing that
               | counts is when the n of 1 is _you_. As another commenter
               | said, you don 't need to live your life by studies. It's
               | not like there is much expense or risk in trying a screen
               | reddener, so try it out, and if it works for you, great -
               | it's bizarre that the author thinks it is "aggravating"
               | that a lot of people use things that they say work for
               | them.
        
         | stuckonempty wrote:
         | Did you read the article? He points out "It's possible that
         | Night Shift does something, but the biggest study I could find
         | of Night Shift mode (still a pretty small study) found little
         | effect on sleep, so if there's an effect, it must be tiny." He
         | links the exact type of observational study you asked for
         | 
         | Regardless the maximum possible effect will be constrained by
         | the biology of the cells responsible for responding to blue
         | light. Maybe knowledge of the biology is incomplete or flawed
         | but to not use it to inform what's possible seems foolish.
         | 
         | So what if it's a placebo effect? Well some people are spending
         | money and time investing in blue light filtering glasses and
         | other solutions. It's potentially snake oil and it could keep
         | them from pursuing better solutions that would actually help
         | them sleep
        
           | Griffinsauce wrote:
           | That sentence does not give me a lot of confidence. The
           | conclusion does not follow the initial statement at all.
        
           | hn_throwaway_99 wrote:
           | If the author goes "I couldn't find enough high quality
           | studies on the topic I'm discussing", then the conclusion
           | should be that we need more studies, not to come to
           | unwarranted conclusions in the absence of actual data.
           | 
           | > Well some people are spending money and time investing in
           | blue light filtering glasses and other solutions.
           | 
           | Ironically, we actually _do_ have a number of good studies on
           | the effects of blue light filtering _glasses_ (easily
           | findable with a Google search) and they do demonstrably
           | reduce onset of sleep time. Where more research is needed is
           | on software-only filters for screens.
        
         | guelo wrote:
         | But you could make your same argument for the pro blue light
         | filter side.
        
           | hn_throwaway_99 wrote:
           | Sure, and I'd write the same thing if we were talking about a
           | blog post that said everyone should use blue light filters
           | because of some plausible physical mechanism.
        
         | energy123 wrote:
         | Blue light blockers are a scam that was created when some
         | circadian rhythm research went viral (in a highly
         | misrepresented way) online a few years ago. It's a stunt to
         | make some quick cash from unwitting buyers.
        
           | storus wrote:
           | My Gunnars give me immediate eye relief after a day of work
           | looking at a display. Are you sure it's a scam?
        
             | disillusioned wrote:
             | To the extent that there's some sort of clinical
             | statistically significant lift over, say, however you might
             | control for a placebo here, who knows? To the extent that
             | it's working for you in a meaningful way, placebo or not...
             | does it even matter? If they're working for you, they're
             | tautologically not a scam, except insofar as you find
             | yourself missing out on benefits promised that aren't being
             | realized, or you feel that the price you've paid is
             | disproportionate to the benefit because some much cheaper
             | option exists in some sense.
             | 
             | Put another way, placebo or not, if there's an effect, and
             | it's a positive one for you, it really doesn't matter. It's
             | working.
        
               | 7bit wrote:
               | The same could be said about homeopathy, but homeopathy
               | is a scam.
               | 
               | The problem is, how do you define "if there's an effect"?
               | A placebo can not have an effect, yet, it has.
        
               | samtheDamned wrote:
               | The whole point of placebo is that it has an effect
               | though, just not one based on a real change.
        
               | storus wrote:
               | That won't work for immediate relief; placebo is studied
               | statistically as a cumulative change over a period of
               | time. Not when I put Gunnars over my sore eyes from
               | computing too much and get immediate relief. Frankly, I
               | find this discussion a bit insane, a bunch of people
               | trying to persuade me "it's all in my head" because they
               | align with the opposite opinion, not with reality.
        
           | hn_throwaway_99 wrote:
           | "It's a stunt to make some quick cash from unwitting buyers."
           | 
           | I've used a number of blue light filters, and I've never paid
           | for them.
        
         | accidentallfact wrote:
         | Even the premise of the idea is wrong, as evenings are either
         | blue from the blue sky, or white from the clouds. It takes
         | exceptional circumstances to have a reddish evening, and even
         | then it's just around the sunset.
         | 
         | I guess that it may help people with undercorrected myopia due
         | to the chromatic aberration, but, I don't know.
        
           | gurkenkram wrote:
           | It is indeed about the sunset and especially the last phases
           | of it. It's also why red light is recommended for night
           | feeding when breastfeeding.
           | 
           | Works for me, both reducing the blue light and worked for my
           | baby, too, using only deep orange and red light of a cheap
           | LED color change lamp. Apparently works for many, since red
           | nursing lights are suddenly sold everywhere.
        
             | Symmetry wrote:
             | The sunset and also fires. Humans have been making fires
             | for a million years and in addition to allowing us to
             | evolve much smaller guts they've also had time exert
             | pressure on our behavior.
        
             | philwelch wrote:
             | I thought red light was recommended for nighttime because
             | it doesn't interfere with natural night vision.
        
           | bawolff wrote:
           | When the sun goes down the amount of blue light goes down.
           | Are you disputing that? Respectfully this feels like a crazy
           | claim.
        
             | DoctorOetker wrote:
             | Well technically during the twilight right after the sun
             | has disappeared below the horizon, or just before the sun
             | appears from under the horizon (when there is no direct
             | line of sight to the sun), the sky is strictly blue-er: the
             | reason the sun and the neighboring angles in the sky
             | appears "yellow/orange" is because green and especially red
             | scattered less through the atmosphere, while a good portion
             | of blue light scatters much more easily on our atmosphere,
             | allowing non-line-of-sight blue illumination on land where
             | the sun has not yet risen or where the sun has already set.
             | 
             | All of humanity has been a witness to these observations
             | and yet we blindly assume blue light filters must have such
             | and such an effect.
             | 
             | But even if it did: suppose a modern concrete-cave-dweller
             | has an out of phase shifted day/night pattern with respect
             | to solar rhythm, having blue light as the last form of
             | light actually seems more natural!
        
               | bawolff wrote:
               | Regardless, the intensity of blue (for that matter, all)
               | light is going to be much lower after the sun sets.
        
         | mock-possum wrote:
         | Plus there's a lot of protein eggs, so they're filling, and
         | have to eat less to feel full, resulting in less food consumed
         | and therefore less opportunity to intake further sources of
         | cholesterol
        
       | daneel_w wrote:
       | In summary blue light filters actually do work, through the
       | indirect action of reducing overall light output, but the author
       | has a larger axe to grind about the "technical details" (it's
       | worth reading the article). The warmer color temperature reduces
       | strain on my eyes, which I find both soothing and invaluable.
        
         | MBCook wrote:
         | The author showed that Apple's implementation only cuts two
         | colors by roughly 50%. And given we perceived light non-
         | linearly aren't they right that that really doesn't make much
         | of a difference?
         | 
         | If someone put up an article saying "Turning down your
         | headphones 1% will help stop hearing loss!" most people are
         | going to ignore it. OK yeah technically it will, but not to any
         | meaningful amount.
        
           | daneel_w wrote:
           | So which do you think it really is? Cutting two wavelengths'
           | outputs in half, or reducing them by a mere 1% as per your
           | trifling comparison?
        
       | scythe wrote:
       | The argument about luminance ranges is wrong. I measure the
       | brightness of monitors regularly as part of my job, and typical
       | maximum luminance values are in the range of 100-500 lux. That
       | puts you right in the steep range of the visual response
       | (especially if you are turning it down and near a max of 100),
       | _which is natural_ -- maximizing the slope of the neuronal
       | response to light means that more information will be available
       | to the brain. In fact a _good_ monitor will be tuned according to
       | the _just-noticeable difference_ which aims precisely to maximize
       | the information available according to this _characteristic
       | curve_. See e.g. the DICOM standard:
       | 
       | https://dicom.nema.org/medical/dicom/current/output/chtml/pa...
       | 
       | The author's basic problem is that he knows too much about the
       | brain and not enough about monitors.
       | 
       | The author goes on to argue that you should be turning your
       | brightness down, but most people already are turning their
       | brightness down; the blue light filter is more comfortable. He
       | does make a reasonable case that you should be reducing green
       | light similarly, but people prefer the incandescent effect of the
       | flux filter to a straightforward color filter -- indeed a primary
       | design goal of these filters has been _to be pleasant to look at_
       | which is why people use them.
        
       | SubiculumCode wrote:
       | I get frustrated with my dim and red shift app that is the
       | default on my android phone for neither being very red nor very
       | dim...but it's the type of app where every scammy body will put a
       | red shift app whoch sucks up your location, contacts, etc, so I
       | haven't changed.
        
       | buggymcbugfix wrote:
       | > That's all great, but there are websites that still don't have
       | dark modes.
       | 
       | Such as that very website? ;)
        
       | zdc1 wrote:
       | I recall studies showing that reading in poor lighting conditions
       | is a cause of myopia in children. So I'm questioning whether we
       | want to be reducing luminance on our devices at all.
       | 
       | I like my (warm-coloured) lights and screens set to max
       | brightness. I find it's easier to read and lets me work with more
       | distance from the screen.
       | 
       | But what about easier sleep? Could we exercise more? Leave
       | screens out of the bedroom? I have no idea.
        
         | zargon wrote:
         | Significant outdoor exposure is essentially the only relevant
         | factor for preventing myopia. I would be interested in seeing
         | any studies that showed any meaningful relevance of low light
         | reading, while controlling for time spent outdoors.
        
           | avadodin wrote:
           | Main factor is genetics.
           | 
           | I was gaming on a blurry CRT and reading on a dim light while
           | hardly ever going outside during my teens and I only have
           | light myopia on one eye.
           | 
           | I don't know if it has ever been studied, but I suspect eye
           | socket morphology from my own family anecdata.
           | 
           | large eyes + small socket = squashed eyes.
           | 
           | It could be different genetic factors for different
           | populations too.
        
             | zargon wrote:
             | I agree that genetics can protect you from developing
             | myopia. For people who are genetically susceptible, outdoor
             | exposure is critically important. Most people won't know
             | which group their children are in.
        
       | Melatonic wrote:
       | Best thing to actually do is use as dim a screen as possible
       | closer to sleep. You can do this with external monitors using DDC
       | and actually directly control the physical backlight of multiple
       | monitors.
       | 
       | Also properly color calibrate your monitors
        
       | icar wrote:
       | I actually get head ache after a long session in front of my
       | computer, but putting anti blue light glasses it goes away or
       | never happens.
        
       | lloeki wrote:
       | > Is half a lot?
       | 
       | > No. Human light perception works on a log scale, allowing us to
       | maintain useful vision over 6 orders of magnitude of luminance,
       | from the sun at noon to moonless nights, whereas halving is .3
       | orders of magnitude. In relative terms, halving light is a tiny
       | blip of the dynamic range of vision.
       | 
       | Kind of missing the point that:
       | 
       | a) a display emits spectacularly less light than the sun, even on
       | very overcast days
       | 
       | b) said "blue light" reduction is presumably intended to happen
       | _at night_ where 1) any comparison with the ability to maintain
       | unsaturated vision in plain sun on a clear day is largely
       | irrelevant and 2) backlight itself is typically lower than in
       | daylight (not for OLED which does PWM)
       | 
       | So given that the amount of artificial light to not screw up with
       | sleep is about equal to "none at all" I'll take a cut in half of
       | what essentially constitutes a flashlight aimed straight at my
       | retinas any day.
       | 
       | > Here are four things that can help. [...] Use dark mode [...]
       | found reductions in luminance ranging from 92% to 98%! That's
       | huge.
       | 
       | From my anecdotal experience dark mode and other low contrast
       | themes are mostly used by people who set their brightness too
       | high, and conversely people switching to dark mode immediately
       | crank brightness up.
       | 
       | Countless discussions I had:
       | 
       | "my battery holds poorly"
       | 
       | "using dark mode?"
       | 
       | "yes"
       | 
       | "try light mode"
       | 
       | "but my eyes!"
       | 
       | "turn brightness down"
       | 
       | "done. wow I just reclaimed 1-2h of battery"
        
       | metalman wrote:
       | my phone has a buried setting for ultra dim, which does help,
       | except outside, where it makes the phone unuseable, and then it's
       | impossible to do the 5 taps and scroll to find it, fuck android
       | going to a linux phone
        
       | duttish wrote:
       | This is just my own anecdotal experience but I usually get tired
       | around 2130-22 but a few times I've turned off the red filter for
       | various reasons (photo editing etc) and suddenly I'm still there
       | at 0030-01.
       | 
       | I'm not saying it's like this for everyone, but it seems to work
       | very well for me at least.
        
       | pvtmert wrote:
       | Interesting take for me is that melatonin (over-)usage can be
       | severely harmful for the individuals.                 ... over-
       | the-counter melatonin supplements can contain anywhere between 10
       | to 30 times as much melatonin as is optimal to maintain circadian
       | hygiene. If you have ever taken melatonin and got immediately
       | knocked out cold, had weird dreams and woke up in the middle of
       | the night sweaty or shivering, you likely took too much--which,
       | to be clear, is not your fault, it's the default in the US and
       | Canada. The mega-doses in stores serve as hypnotics (punches you
       | to sleep), but wreck sleep architecture. The right dose is ~0.3
       | mg, which is hard to find in pharmacies but can be found online.
        
       | xmodem wrote:
       | > Unless your strategy is to create a photo-lab-like screen in
       | pure black and red, or wear deep-red-tinted glasses, it's
       | unlikely that a pure colorshift strategy will cut out that big of
       | a chunk of the spectrum.
       | 
       | The writer is dismissing this out of hand but to me this sounds
       | like a great idea.
        
       | pvtmert wrote:
       | My overall take (elephant in the room): Blue light filters don't
       | work, it depends on what you do & how you do it.
       | 
       | For example, most people keep watching/scrolling Instagram Reels
       | and TikTok videos. They keep stimulating the brain constantly,
       | not just at electrical level but also in emotional/chemical level
       | too.
       | 
       | I have seen people who are _addicted_ and cannot get rid of the
       | addiction. This is not only the dopamine-boost, it has deeper
       | connections of neuro-chemical stimuli. Just observe around you;
       | people pick up their phone to directly open Insta /TikTok, start
       | scrolling right away every 5-10 seconds. (watching stories
       | included too)
       | 
       | This is to some extent that when you mention even the possibility
       | of such addiction and abnormal behavior, one gets outright
       | resistance and denial of addiction itself. Much like substance
       | abuse...
       | 
       | My point is, majority of the population watches/scrolls these,
       | needing 10g of melatonin to fall asleep.
       | 
       | Obviously if I get engaged in an interesting stuff continuously,
       | the existence of blue light does not matter that much. It matters
       | if/when I am reading a novel which is in a mediocre chapter where
       | nothing _that_ interesting going on. The existence of blue-light
       | or lack thereof may tip the scale at that point.
        
       | rcore wrote:
       | > That's all great, but there are websites that still don't have
       | dark modes. It doesn't make any sense in 2026 that Gmail doesn't
       | have a dark mode. If the activity you're doing most at night is
       | reading email, you might consider an alternative email client.
       | 
       | This reads funny on a website that does not respect your device's
       | dark mode. Guess I'll look for an alternative blog.
        
       | jedberg wrote:
       | >It doesn't make any sense in 2026 that Gmail doesn't have a dark
       | mode
       | 
       | I've been using dark mode on gmail for years, not sure what OP is
       | talking about here.
       | 
       | But also, my sleep quality got much better when I turned on
       | f.lux. And it got better still when I added a second light to my
       | bathroom that can do a 1800K super-warm light (that's also very
       | dim).
       | 
       | And as an added pro-tip, I use f.lux during the day to cut my
       | color temp to 5900K (instead of the default 6500K) and it made a
       | huge difference for how long I could work without getting tired
       | eyes.
        
       | snowhale wrote:
       | the real variable is probably what you're doing before bed, not
       | the wavelength. scrolling social media keeps the brain actively
       | processing new stimuli -- notifications, comparisons, emotional
       | content. reading on a kindle with blue light filter probably
       | sleeps better than watching youtube with it on. the luminance
       | thing the author mentions points in this direction too.
        
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