> Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light.
Yeah, max brightness is probably going to make an impact. I bet if you were in a room with a bright light reading a book, with an equivalent amount of lumens going into your eyeballs, you'd probably have a tough time sleeping. This study seems like it was set up to generate a certain set of results. I wonder how it would look if the quantity of light was controlled for.
Additionally, the comparisons to the incandescent spectrum and the freaking out about the blue peaks (which seem pretty small) was over the top. The incandescent spectrum contains blue, and the "peak" of the other spectra would contain an equivalent integral of blue light as compared to a slightly brighter incandescent light.
Just turn the lights down low at night and get some warm spectrum bulbs and you'll be okay.
I am disappointed that many phones/tablets don't go very dim.
From flagship to cheap, it seems that if you're in a pitch black room and check the time on your phone, the light will illuminate the whole room, even on the dimmest setting.
I actually modded my phone by putting a resistor in the LED backlight circuit, which divided the brightness by 1000 - and it was still plenty bright at night (human eyes are logarithmic, so dividing the brightness by 1000 doesn't have as much visual impact as you'd expect).
A Macbook's minimum brightness is quite bright. The thing that annoys me no end is that if you hit the "dim" button when it's at minimum brightness, it goes black - but fades out slowly and smoothly. So they're clearly capable of being dimmer, but Apple decided we're not allowed that.
I used to feel this way, but since learning that much of the advanced functionality is unlocked by Opt/Shift/Ctrl or some combo of them + click, I find myself digging that consistency more and more. At this point if I don’t see the option I need, I know 9/10 it’ll show up when I opt+click.
I have a small python script responsible for dimming my thinkpad + external display; it takes an argument like 'b * 0.95' for 5% reduction, reads HW + SW brightness, and lowers HW brightness to minimum before then reducing the SW brightness.
Pretty nice and the only recent change I've made is making it re-evaluate the expression based on frequency of keystrokes (so 3 brightness-down keys in 1s becomes 9 evaluated decreases in brightness).
iOS actually has a hard to find setting that lets you make the screen super dim. It's been a lifesaver when using my phone in the evening. To enable it go to Settings -> Accessibility -> Zoom and then tap the Zoom toggle switch.
Once that's enabled iOS will now bring up a super secret popup menu whenever you double tap the screen with three fingers. From the little popup menu go to Choose Filter -> Low Light and your screen will go dimmer than is normally possible. With this on and the normal brightness mode set to its lowest setting the screen can get quite dim indeed.
There’s two settings you can use in tandem to get an OLED iPhone brightness even lower than that.
First is the zoom trick you’ve already described, then you can use the “reduce white point” display accessibility setting to apply even more darkening.
With minimum display brightness, low-light zoom mode and white point reduction set to 100%, the display gets very very dim. If you do this in normal lighting conditions, the display is basically impossible to see.
> Once that's enabled iOS will now bring up a super secret popup menu whenever you double tap the screen with three fingers.
On current iOS you don't need to be in zoom and double tap. The zoom filter is also available by tapping the "Zoom Filter" setting which is 6 items below the Zoom setting in Settings -> Accessibility -> Zoom. The double tap in zoom thing is there to make it easy to quickly change the filter while zoomed.
This and the white point setting void-pointer suggested are both controllable from Shortcuts.
There is a Zoom action that supports turning zoom on, off, or toggling it, a White Point action that supports turning it on or off, and a Brightness action that supports setting the brightness to a given percentage or asking for the brightness.
I just tried making two Shortcuts, "Low Light" and "Normal Light".
Low Light:
Turn Zoom On
Turn White Point On
Set Brightness to 0%
"Hey Siri, Low Light" then works. It does leave you zoomed, so you need to cancel that, but then you are left at 0% brightness and whatever Zoom filter you have set is in effect. "Turn White Point On" will set the white point reduction to whatever percentage you have it set to in the Reduce White Point system settings.
Normal Light:
Turn Zoom Off
Turn White Point Off
Set Brightness to <ask each time>
That does what you'd expect. Siri asks you what brightness you want from 0 to 1. You can change that to a specific percentage if you don't want to be prompted.
PS: This only fully works on iOS. On iPadOS zoom filters only work while actually zooming, and then only apply to what is shown in the zoom rectangle. On iOS the zoom filter applies when zoom is enabled regardless of whether or not you are actually zoomed.
The white point reduction does work on iPadOS so you do get some lowering of minimum brightness but not as much as on iOS when you can use both.
Yes, I use this trick. You can adjust the filter to your heart's content. But I agree with the parent here that it should go dimmer as-is and we shouldn't need this. I'm not sure how light perception works, if it's a logarithmic thing like noise, but if not, this scale should probably be logarithmic instead. Or even moreso if it already is. Because I think we generally don't care exactly how bright it is if it's bright daylight and we need to max it, but conversely care much more for reaching the dimmest levels if we're in bed (or if we don't care, we probably should according to the article).
iphones are all OLED now, so there is no distinction.
On an old LCD display there are some filters that do a linear/nonlinear mapping from 0->255 brightness to 0->64 for example, leaving the actual backlight at the same brightness. The downside is that colour banding and quantization start to get really bad - and 'black' starts to look very non-black.
My older iphone is not oled so that would explain why I did not like this setting when I tried it some time ago like what you say about blacks looking out of balance. Thanks
My iPhone can go super dim, to the point that it's hard to see in a dark room. I use no special features.
Also, Kobo's eBook readers can go very very dim, and can be comfortably read in a zero light room. The max brightness I use is 29%-31%, dependent on lighting. My reader has a fixed light, but newer ones also adjust light temperature automagically, and much more comfortable to read (got one as a present for my dad).
I keep Extra Dim on at all times to lower the peak nits and to further dim the screen when using Night Light to read after dark.
The biggest saviors to my longtime night reading habits, though, have been OLED and how many websites and ebook apps have competent true black dark modes.
Another solution may be to use filtering glasses. Not "blue light glasses" but an FL-41 tint, which can help with migraines, light-sensitive conditions, and circadian rhythm issues[0]. This is a pinkish or amber-ish color tint.
What I find far more concerning is the brief mention in the article about the explosion in outdoor lighting, which is massively disrupting the little remaining wildlife we have left (and nevermind destroying any hope of a glimpse t a dark sky). And there is absolutely zero reason for it other than ignorant wrong ideas that it helps traffic accidents or reduces crime (it does the opposite). Calling it cargo-culting would be kind.
One of my favorite features on my Pixel 7 Pro is the "Extra Dim" feature, especially since the Netflix app has started enforcing a minimum brightness level that's much too high in dark environments.
There’s a full-color dimming filter in Accessibility -> Zoom -> Zoom Filter -> Low Light. You can assign it to the accessibility shortcut for quick access.
They do... But thats down to poor design decisions.
Human vision extends from about 10^5 cd/m^2 to 10^-5 cd/m^2 [1].
Typical backlights use something like PWM to modulate the brightness. That means you need to be able to scale your backlight by a factor of 10^10 to cover the whole human vision range. And if your CPU runs at 1 Ghz (10^9), then at the dimmest setting then even being on for a single clock cycle would be a flash every 10 seconds - clearly unacceptable, and even then, few backlight controllers could handle a 1 nanosecond pulse!
The fix is to use PWM combined with settable 'modes'. The modes could be 'bright light' (using all the backlight LED's, perhaps a few watts total), and a dim light mode, which uses just one LED through a high value resistor, of just a few tens of microwatts. Your two modes have a factor of 10^5 between them in brightness. So now the PWM on your CPU only needs a resolution of 10^5, which it can do.
> That means you need to be able to scale your backlight by a factor of 10^10 to cover the whole human vision range.
Uh, phones don't produce brightness that high. And the low range is "too low" for usefulness anyway. Your math is off by few factors
> And if your CPU runs at 1 Ghz (10^9), then at the dimmest setting then even being on for a single clock cycle would be a flash every 10 seconds - clearly unacceptable, and even then, few backlight controllers could handle a 1 nanosecond pulse!
CPU is not doing PWM, it's separate chip
And you can't realistically have more than few kHz of PWM frequency anyway coz of losses.
It's not really a technical problem in the first place, it's easy technically, just have 2 current sources, when you need low light you just PWM the low current one. And not "just putting resistor in series", that's extremely wasteful, or "single led" that would just not illuminate evenly.
Unfortunately at these low currents, you tend to get a tiny amount of leakage across the LED junction - just a few microamps, but trying to make a small amount of light it becomes an issue. Worse, you can't even calibrate for it because the leakage is highly temperature dependant.
Compare your hypothetical 10^10 range to the range offered by typical LCD monitors, where maximum is in the 300...400 cd/m² range and a minimum brightness less than 30 cd/m² is "outstanding". I.e. a 1:10 range.
This is how I activate/deactivate the “Zoom” accessibility setting with the “Low Light” filter (and the zoom level stays at 100% unless I double triple-finger tap!)
Also a Pixel owner - Try wiggling the light as you walk.
Your motion sensing kicks in before either your focus or dark vision, and even if you can't "see" it, your brain can get enough information to let you navigate.
I’m really turned off by how there’s zero critical consideration of their quoted research. They’re just hammering you over the head with quantity.
Sleep is like diet where there’s virtually no scientific consensus on even the most basic things. Plenty of studies which conclude “more research is needed”, though. That leaves people free to cherry pick and go deep into the weeds with crazy the-world-is-falling theories.
Diet certainly has some basic things that are agreed upon, like caloric intake affects weight gain/loss, and it's healthier to eat vegetables and fruit than meats and grains. Sure, there's a lot of argument about the specific or how beneficial some of these things are, but it's not as bleak as you make it out to be.
>’m really turned off by how there’s zero critical consideration of their quoted research
I can take a variety of stimulants which would normally keep me up all night, but 5mg of Vit K2-MK4 removes enough of the calcium from my bloodstream so that it can't amplify the effects of the catecholamines and I'm asleep within 30mins, its actually better than taking melatonin or anti-histamines.
I've been more alert and observant as a car passenger whilst on 2 NHS prescribed benzodiazepines than the person driving the car! I think sometimes its a state of mind which makes its hard to sleep.
That's interesting! Can you provide some links to evidence regarding Vit K2-MK4, its effects on calcium in the bloodstream, and how that inhibits the effects of catecholamines and leads to sleep induction?
Vit K2-MK4 Osteoblasts better than Vit K1 in my experience, ie 50mg of K1 is nowhere near as good as 5mg K2-MK4. Calcium amplifies the effects of the catecholamines which probably explains why tea drinkers prefer hard water. Military also give out tea, during and after a exercise. High Vit A and Vit D can also lead to hypercalcemia which makes you feel good.
https://scholar.google.com/
Remember Thomas Pynchon and be mindful of the fact that search engines wont always give you the studies you are looking for, so you have to go back and perform the same search's weeks and months later.
What are you trying to achieve? Because I could also add, your omega 3 intake can also be a factor, Omega 3 reduces the number of osteoclasts for the flip side of the bone health and also increase the size of neutrophils which will engulf bacteria which invariable destroy bones and leads to arthritis and rheumatoid arthritis.
Growth hormone, either 95% of tryptophan via the kynurenic pathway or nicotinic acid on an empty stomach will increase the number of neutrophils, although medical experts will normally give intravenous growth factor aka growth hormone. Stress hormones like adrenaline will reduce the effectiveness of neutrophils (Left shift iirc) as will a B12 deficiency (neutrophil hyper segmentation). Omega 3 will increase the neutrophil size by just under 40% so that they are large enough to consume yeast cells, which makes me wonder if brewers yeast is potentially harmful. Manganese Ascorbate is also useful because much of the vit C is stored inside the neutrophils, so larger neutrophils mean high levels of Vit C, and the manganese can contribute to MnSOD to neutralise ROS inside the mitochondria and help to repair cartilage in places like knee joints.
Omega 3 also help the serotonin and melatonin in the brain and spinal fluid which also helps with getting to sleep.
When the UK govt were giving cod liver oil and malt to kids in the 50's or 60's, under the pretence of preventing Ricketts, they knew what they were doing to control future GDP and aggression levels.
Considering the Japs are experts in Vit K studies, and prescribe K2-MK4 to post menopausal women who are naturally consuming an iodine and omega 3 rich diet seafood diet and also happen to have some of the longest living females in the world, and some of the highest IQ's in the world, I think looking to them will give you more info than a typical western diet.
Just 150micrograms of T3 (Triiodothyronine - one iodine atom removed by selenium, with 80% of this T4-T3 conversion taking place outside of the thyroid gland) will half the time spent in Intensive care in hospitals. Tyrosine is the main ingredient of T3 (hormone) & T4 )pro-hormone) so your metadata for getting more tyrosine in your diet is when you start to get grey hairs.
Many govts, like the UK Govt are deliberately harming the population with their treatments provided by the health care system and what is taught at med school, which clogs up beds and pushes up house prices with the elderly who dont want to go into nursing homes. A crude example of Maslow's Hierarchy of Needs, an agenda many govt's are now following around the world.
And choline can also reduce stress levels by reducing the CO2 build up in the body and lungs. Choline is used in the alveoli of the lungs to facilitate the gas exchange, its also used in the cell walls and the connection between neurons. The more choline you consume, the better your physical performance and mental ability. Personally I found L-Alpha glycerylphosphorylcholine to be best, but yet to try citicoline which is used in hospitals for brain injuries and costs about £3k a kilo.
Sleeping next to a bright fire though, is way more easy and cozy, than sleeping next to a bright LED flashlight.
The red light (and sound) of the fire has a very soothing effect, which has probably something to do that our ancestors slept next to it since ~1 mio years.
(it is still fun, just don't use a new sleeping bag, as it might get holes)
I'm glad our ancestors were less worried about the quality of their sleep and more worried about what beasts might attack them during the night and using fire to keep them away, otherwise we may not be sitting here discussing how LED lighting impacts sleep quality...
actually, infrared light from campfires improves sleeping quality because it triggers melatonin production in the brain. In contrast, blue bright light triggers cortisol production.
And yet there are all those other datapoints that also support the central thesis that you aren't cherry-picking here. So perhaps the author's point stands?
I think OPs point is people tendency to use LEDs in way that is bad for melatonin production is not the same as LEDs being inherently bad for melatonin production as the title suggests.
Many LEDs have fine color spectrum and brightness setting and people should take those capabilities into mind when purchasing, especially for lights they will be using in the evening. Personally I’ve invested in hue lights and have them configured to dim and redshift as bedtime approaches.
Uh, just no. LED lighting have modes of working that can be bad. You just need to be way more picky and knowledgable with LED lights which is hard for most customers, vs "just buy an incandesent bulb"
Nice "well actually" there. So is the proposal consumers perform their own spectrographic tests before making a purchase or can we just go with "leds are bad" given the overwhelming majority of the products available on the market demonstrate harmful characteristics with no clear way of discerning which are the outliers at time of purchase?
So you start with just no and then proceed to argue my point for me? Weird flex but ok. Anyway it's nice to see the quality of discourse hasn't degraded on HN over the years.
Yes, the study [0] used iPads (on maximum brightness).
Some releveant quotes:
"The randomized, crossover protocol design consisted of two conditions: (i) reading an LE-eBook (iPad; Apple Inc., Cupertino, CA) in otherwise very dim room light for ∼4 h before bedtime for five consecutive evenings, and (ii) reading printed books in the same very dim room light for ∼4 h before bedtime for five consecutive evenings."
"Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light."
"Lastly, although the short-wavelength light from the LEeBook may have been responsible for the effects reported here, this study did not include a light-emitting device with longer wavelength for comparison, so our findings may be due to the difference in irradiance level rather than spectral composition."
> Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light.
Yeah, max brightness is probably going to make an impact. I bet if you were in a room with a bright light reading a book, with an equivalent amount of lumens going into your eyeballs, you'd probably have a tough time sleeping. This study seems like it was set up to generate a certain set of results. I wonder how it would look if the quantity of light was controlled for.
Additionally, the comparisons to the incandescent spectrum and the freaking out about the blue peaks (which seem pretty small) was over the top. The incandescent spectrum contains blue, and the "peak" of the other spectra would contain an equivalent integral of blue light as compared to a slightly brighter incandescent light.
Just turn the lights down low at night and get some warm spectrum bulbs and you'll be okay.