Blue light is very, very bad.

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MtnDon
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If you are a mouse, warm colored light may be worse for sleep than blue light

https://www.businessinsider.com/night-mode-shift-warm-colors-worse-for-s...

Starkm32
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Was under the impression cruiser lights are blue this side of the Mississippi, and red
On the left.

Like radio call signs start with “W” east of Miss, and “K”, west.

Of course, it may be a myth ….

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MtnDon wrote:
If you are a mouse, warm colored light may be worse for sleep than blue light

https://www.businessinsider.com/night-mode-shift-warm-colors-worse-for-s...

this sounds totally backwards

But the new study, published in Current Biology and led by Dr. Tim Brown, suggests that it’s more natural to look at blue light in the evening and warm light during the day. That may be because natural light is actually bluer during twilight.

my sunsets look orange, not blue… imo there is more blue during the day

next they show that blue light helps mice sleep better

The team of researchers used specially designed lighting on mice in order to test how different wavelengths affected sleep patterns. Blue light proved less disruptive to mice’s sleep than yellow light of the same brightness, according to the researchers.

but wait, mice are nocturnal.
They want to sleep during the (blue light) day. At night, when mice are active, it makes sense that warm light would help them stay awake.

so yes
for a mouse, blue light is associated with sleeping

for a human
blue light is associated with activity during the day
at night blue light interferes with sleep, in humans… maybe not in nocturnal creatures, like some patrol cars… lol

hank
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Yep. I don’t regard “BusinessInsider” as a reliable source of scientific or health information.

They spin toward, well, business interests.

mr_magoo
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kmart sucks.

Sari33
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Sarcasm not needed,
It’s a fact that Blue light can be dangerous for Retina,that depends about intensity and concentration of the emission
Much important is the assuefation that people have for the artificial light.
You will want an ever stronger light

wle
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what is “assuefation” supposed to mean?

oh wait

assuefa*c*tion
assuefaction (ˌæswɪˈfækʃən)
n
the condition of being or becoming familiar with or used to something

merriam webster also says it is obsolete

come on – obsolete word, plus mis-spelled – – did anyone else know that?

wle

"You never have the wind with you - it's either against you, or you're having a good day."
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It never gets easy, you just go faster.   
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       ,ø¤º°`°º¤ø¸,ø¤º°`°º¤ø¸,ø¤º°`°º¤ø¸

L4M4
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Sari33 wrote:
It’s a fact that Blue light can be dangerous for Retina,that depends about intensity and concentration of the emission

So, red, green, white, or yellow light in high intensity and concentration ist absolutely harmless to look into? Wink

Quote:
Poison is in everything, and no thing is without poison. The dosage makes it either a poison or a remedy.

Paracelsus (YouTuber or Influencer or something like that)
slmjim
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wle wrote:
VERY uncommon word, come on did anyone else know that? wle

Eschew obfuscation.

 

slmjim

Great... Carnac the Magnificent tells me I just signed up for yet another expensive hobby.

Smile! It makes others wonder what you've been up to.

hank
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It’s one of those nasty science problems where the tool used to observe biological tissue changes what’s observed.

Quote:

… It is now well understood that such light doses, and in some cases any light at all, can negatively affect sample fitness and viability.

This phenomenon, typically referred to as photodamage or phototoxicity, is a widely observed but rarely reported effect wherein researchers unwittingly change their sample simply by observing it. The extent to which these changes have affected the interpretation of imaging experiments is difficult to assess. However, as microscopy methods for studying living specimens are evolving rapidly and becoming increasingly in-demand, the time is right for developers and biologists to seek a more quantitative understanding of the effects of light on samples.

https://www.nature.com/articles/s41592-018-0170-4

BurningPlayd0h
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mr_magoo wrote:
kmart sucks.

This is underappreciated.

djozz
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L4M4 wrote:

Quote:
Poison is in everything, and no thing is without poison. The dosage makes it either a poison or a remedy.

Paracelsus (YouTuber or Influencer or something like that)
Party
Muto
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Sari33 wrote:
Sarcasm not needed, It’s a fact that Blue light can be dangerous for Retina,that depends about intensity and concentration of the emission Much important is the assuefation that people have for the artificial light. You will want an ever stronger light

Dude, we LIVE on sarcasm, it is what keeps the gun out of our mouths for another week.
Don’t want sarcasm? Find another forum, cause this ain’t it Smile

PS. Blue light still sucks and so does Disco

“History doesn’t repeat itself, but it sometimes rhymes,” Mark Twain

After the Apocalypse there will be only 2 things left alive, Cockroaches and Keith Richards

“You’ll develop like a herd mentality,”
“It’s gonna be herd-developed and that’s gonna happen.”

Yep it already happened

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Muto wrote:
PS. Blue light still sucks and so does Disco

No it doesn’t.

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Guys, no political or controversial topics are allowed here on BLF. I’m sure disco is one of them. Big Smile

Lightbringer
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Jerommel wrote:

Whoa. That guy looks like a cross between Joshua Jackson and a (very) young Sam MacMurray.

09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0

Muto
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Disco back beat but more Electronica.

Kraftwerk with bass:)

Love the
We are Showroom Dummies!

“History doesn’t repeat itself, but it sometimes rhymes,” Mark Twain

After the Apocalypse there will be only 2 things left alive, Cockroaches and Keith Richards

“You’ll develop like a herd mentality,”
“It’s gonna be herd-developed and that’s gonna happen.”

Yep it already happened

BurningPlayd0h
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If there’s gonna be a war, I’m picking a side.

Synthpop >>> Disco

KawiBoy1428
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Muto wrote:
Sari33 wrote:
Sarcasm not needed, It’s a fact that Blue light can be dangerous for Retina,that depends about intensity and concentration of the emission Much important is the assuefation that people have for the artificial light. You will want an ever stronger light

Dude, we LIVE on sarcasm, it is what keeps the gun out of our mouths for another week.
Don’t want sarcasm? Find another forum, cause this ain’t it Smile

PS. Blue light still sucks and so does Disco


I was a D.R.E.A.D. Gold Card carrying member (DREAD=Detroit Rockers Engaged in the Abolition of Disco). Disco still sucks Tony, Kick Ball Kick Ball…Trans-Am Big Smile

KB1428 “Live Life WOT

Lightbringer
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Wow… I’m, like, back in high-school again.

09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0

Sari33
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Muto wrote:
Sari33 wrote:
Sarcasm not needed, It’s a fact that Blue light can be dangerous for Retina,that depends about intensity and concentration of the emission Much important is the assuefation that people have for the artificial light. You will want an ever stronger light

Dude, we LIVE on sarcasm, it is what keeps the gun out of our mouths for another week.
Don’t want sarcasm? Find another forum, cause this ain’t it Smile

PS. Blue light still sucks and so does Disco


It depend how you want discuss the topic.
If you like sarcasm,ok Boss Beer
cr313
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Try photography, the light just after sunset is called the blue hour for a reason.

SKV89
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jon_slider wrote:

The team of researchers used specially designed lighting on mice in order to test how different wavelengths affected sleep patterns. Blue light proved less disruptive to mice’s sleep than yellow light of the same brightness, according to the researchers.

but wait, mice are nocturnal.
They want to sleep during the (blue light) day. At night, when mice are active, it makes sense that warm light would help them stay awake.


Good observation! Thumbs Up Thumbs Up

These kinds of articles are so misleading especially for the vast majority of the population that don’t apply critical thinking to what they read.

Btw, I really need to thank this post. For the past few days I’ve been wondering why my eyes were strained so bad in the evening. Then this post popped up and triggered me to check my night light settings on my PC and that’s when I realized a recent update caused the night light to reset to off. I just turned nigh light back on and my eye strain is gone pretty much immediately! For those affected by eye strain in the evening, try turning on nigh light or night shift. It really works! Blue light really is bad in the evening!

Sari33
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https://www.ledsmagazine.com/leds-ssl-design/article/16695634/bluefree-w...
Another article That explain how high peak of Blue present
on many emitters(also warm and neutral) make inhibition of melatonine and
then sleep problems on night when Leds are more used…

hank
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Yep. But remember the free market in ideas is at work. Industry finds it far more profitable to produce blue-white emitting LEDs than to go to the trouble of designing and producing those same basic emitters with a complex and pricey phosphor coating to intercept that blue and make the output warmer. Same reasoning works for flashlight makers — cool blue-white is cheaper.

Not to mention the market disruption that will be caused when those basic blue-white emitting products are displaced by the newer violet-emitting LEDs. There’s a real scramble going on to fight against the medical advice.

Omega_17
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So we are getting more violet light to avoid blue light? sound like its a good idea leading to a possible worst situation. UV is the worst for retina.

hank
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Violet (which is above 400nm) is visible light, although it takes a whole lot of it to trigger the visual perception of light.

Look at the chart, human vision is (slightly) sensitive down as far as 400nm

That may be the increasingly yellow lens that goes with aging, blocking the shorter wavelengths.

Fortunately LEDs are narrow bandwith light sources, so it’s possible to pick an emitter within the violet (above 400 nm) but outside the also narrow range of blue
{peaks in the blue portion of the light spectrum around 460 nm, most effective in the range between 446 and 477 nm} that affects the human blue receptor.

Yeah, violet photons are going to pack more energy than blue, somewhat less than UV, and I’d clearly want them completely absorbed by the phosphor, not leaking out the sides of the emitter the way we see making blue rings around yellow hotspots in flashlight beams.

You’re quite right to suspect there may be serious problems when people start hyping “no blue” or “retina safe” violet-pumped emitters without close attention to the wavelengths. New problems, that is.
A great experiment is underway ….

Any photon from somewhere in the far blue on to higher energies can knock electrons off of molecules, which is not healthy.

Quote:
The Photoelectric Effect – Optics Lessons
optics.mbhs.edu/photoelectric/optics.mbhs.edu/photoelectric/

… We must convert this to electron volts (eV) by multiplying by 6.24*10 18, to get 2.17 eV. Electron Energy . A photon is like a tiny blob of pure energy. In the photoelectric effect, an electron is hit by a wandering blob of energy and is so excited that it breaks its bond with the atom to which it is held….

SKV89
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Personally I think violet light is even more harmful to our eyes than blue despite I don’t have any scientific evidence to prove it. Violent is a shorter wavelength and higher energy than blue. I would love for someone to prove my assumption wrong but unless there is solid evidence proving violet is less harmful than blue, I will take blue over violet for day-to-day ambient lighting.

hank
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PS, found with ‘oogle:

Quote:

Stephen Westland, Professor of Colour Science at University of Leeds

Answered Nov 28 2019 · Author has 980 answers and 597.1k answer views
Light cannot be both blue/violet and invisible at the same time. Before we answer your question we need to define what we mean by uv light.

We can divide uv into three bands

uv-A 315–400nm

uv-B 280–315nm

uv-C 100–280nm

Although there is variation from one person to another the lower level of human vision is at 360nm.

Therefore light below 360nm is invisible and by definition has no colour.

Light in the range 360–400nm is technically uv light but is visible and looks violet or blue violet.

So some uv light is visible but most is invisible and has no colour.

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