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Chemists discover how blue light speeds blindness

phys.org

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Re: Chemists discover how blue light speeds blindness

#251

Post by herf »

copperx wrote: post #242
wpasc wrote: post #156

Earlier quoted context omitted.

Thank you for your input, but I mostly want to thank you for f.lux. It has been one of my favorite things for a long time. It's silly how long it's taken companies to provide a native blue light filter and your product just kicks ass. If you guys ever wanted to figure out your app on a smart TV (or apple TV), I know there'd be a lot of thankful people! Also, I'd love to contribute to the ongoing dev of f.lux (I don't…

I just want to remind everyone that LED backlights emit blue light that isn't eliminated by f.lux or similar utilities.

You might want to refer to our measurement project for some numbers:

https://fluxometer.com/rainbow/

Also, you can be below threshold for circadian responses just by being very dim.

Re: Chemists discover how blue light speeds blindness

#253

Post by klodolph »

driverdan wrote: post #205
klodolph wrote: post #151

Earlier quoted context omitted.

What makes f.lux inaccurate? Color perception is relative and if you are in a dark room, your eyes should adjust to different white points naturally. This is the same thing that makes it so a white piece of paper looks white no matter whether you are inside or outside, even though the actual light reflected from the paper has a radically different spectrum in each case.

I'm not OP but I can't stand f.lux and its clones. I never adjust. The inaccurate colors stand out to me no matter what the conditions are.

"Inaccurate" is definitely an incorrect way to describe the colors. The colors are correct from relative colorimetric perspective, you're just changing the white point.

Re: Chemists discover how blue light speeds blindness

#254

Post by userbinator »

hinkley wrote: post #190
Forge36 wrote: post #183

Earlier quoted context omitted.

I'm running f.lux on my work PC (tones down a bad otherwise VERY bright-blue monitor). Thank you for reading/writing out your interpretation of the article so clearly (highlighting points others are likely to trip on not coming from a related background)

Have we fixed the “optimized for electronics store demo” problem with monitors yet? Part of my ritual of setting up a new monitor is to turn down the brightness and increase the contrast. They almost always default to very bad values. Brightness, temperature and green/blur balance are all off for an office setting. In the worst case the backlight was capable of outputting twice as much light as I really needed.

When I got my first LCD monitor, the first thing I did was turn the brightness down to 0 and the contrast to slightly above; at that point it was already plenty bright enough, and after a few years when I noticed the brightness begin to fade I increased it 2-3 notches.

I suspect part of it is also planned obolescence --- when the backlight is running at full brightness, its lifespan is greatly decreased. Now the aforementioned monitor is approaching 15 years of age and brightness has reached 20/100, so there's still plenty of life left in it.

Re: Chemists discover how blue light speeds blindness

#255

Post by herf »

mafuyu wrote: post #182
herf wrote: post #172

Earlier quoted context omitted.

Yes, also if your eyes are closed when it starts, 500nm is better because more gets through the eyelid. Better if you diffuse more and spread out the light over more of the visual field. But the main thing you'll want to make sure is that you can get enough light. There is some evidence that >200 lux with this wavelength will help, but most light therapy uses tons of light (1500 melanopic lux or more): https://fluxom…

Thanks for the tips! That link is super interesting. I'm guessing melanopic lux is the lux output weighted over the spectral absorption curve of your eyes? Some napkin math: I have ten 3W LEDs, and each might produce around 1000 lux when fully driven. If we drive each at half strength, and half of the generated lux is melanopic lux, that's 2500 melanopic lux.

Yes, lux depends on the viewing distance. Lumens is related to total light in all directions, and lux is "per area" (i.e. gets smaller with 1/distance^2).

Melanopic is weighted by the non-visual response in the eye, and this number corresponds pretty closely to the spectrum that drives circadian effects, and likely, mood. So whereas an incandescent might be 0.45 melanopic lux per visual lux, a really blue sky (or a 500nm LED) is around 2.0 "M/P".

Re: Chemists discover how blue light speeds blindness

#256

Post by herf »

nathan_long wrote: post #168

I am excited about LED lights for their efficiency, but keep seeing articles like this and don't understand the practical ramifications, like "what bulbs should I buy?" I messaged Cree on Twitter, expecting a very corporate response, but they linked to some studies (which I haven't yet had time to explore.) FWIW - https://www.energy.gov/eere/ssl/street-lighting-blue-light-a... and https://www.lrc.rpi.edu/resources/ne…

The message is: there is no more risk from LED than older sources, by the metrics we have now.

I would suggest that one problem is that LEDs don't "warm dim" (unless you get some special ones from Philips and a few others), and people tend to dim them less overall.

Re: Chemists discover how blue light speeds blindness

#257

Post by slothtrop »

erikbye wrote: post #166
arama471 wrote: post #161

Earlier quoted context omitted.

I assume you mean the night light button in the action center? If so I would argue f.lux does a lot more. For one thing you can choose the hue it goes to, but also unlike the Windows 10 one which (AFAIK) is simply on/off, f.lux will adjust based on a schedule which means that you don't typically notice the effects (as the change happens slowly). This, combined with the ability to change damn near every parameter it u…

Both macOS and Windows 10 has on/off now, scheduling, less/more warm adjustment. Windows 10 even has sunset to sunrise based on location. EDIT: HN is becoming more like Reddit every day, I see. Ridiculous. Down-voted for pointing out the existence of helpful features. EDIT: might have been my fault.

There was nothing wrong with your tone.

Re: Chemists discover how blue light speeds blindness

#258

Post by perilunar »

dewiz wrote: post #224

Now I’m wondering about the damage of all those Windows crashes and blue screens :-) Seriously though, the sky is blue, the sea is blue, how come we’ve evolved into beings affected by blue light??

Yeah, but they're only blue during the day!

Re: Chemists discover how blue light speeds blindness

#259

Post by lucb1e »

dsr_ wrote: post #177
_nkoa wrote: post #32

Earlier quoted context omitted.

Because of the way your eyes work. If it is bright, your pupil will be shrunk, to not be blinded by the luminosity. When it is dark, your pupil will be opened wide up. It is this principle that camera apertures are based on. Now if you have your pupil wide open in a completely dark environment and put a 100% brightness screen at ~10cm of your eyes, what do you expect will happen ? Our eyes are made for nature, that m…

... but I don't put a 100% brightness screen in front of my eyes at night. Do people really do that? Don't they know how to adjust brightness? Indoors, I use about 30% brightness. As the day gets dimmer, that slides down to about 25%. If I'm reading something in bed, I start at about 10% and as my eyes adapt, go down to 1%. When I'm finding it hard to keep my eyes open, I take that as my signal to go to sleep. Am I r…

I do for videos because I notice that I just see a lot more. Turning down the brightness is like turning down the light in the room that was filmed in. That's both on OLED and on LCD screens (wish I could go back to OLED, though, but it has gotten fairly rare among cheaper phones).

Re: Chemists discover how blue light speeds blindness

#260

Post by spaceandshit »

herf wrote: post #136

f.lux author here, still slogging through the article. It is hard to understand the light levels used because they use "power" (uW, mW) from a laser, and not "irradiance" (uW/cm^2 or mW/cm^2), so which area they have concentrated that light over is hard to understand. All I can see is it is from a laser, so the irradiance could be extremely high. The human lens filters most light at the peak of the given spectrum for…

I'd like to thank you as well. I jailbroke my iPhone just to get flux on there (before Night Shift), and still prefer it over Night Shift.
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