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Old 13th August 2018, 16:48   #16
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

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Originally Posted by Samurai View Post
I don't think so. The old tubelights were so popular because of their high lumen output.

Check the last line of post#8.
Ah ok. Was an idle wonder

And oops didn't see the link you had put up. How are those lights? Been thinking of buying something similar to that from Philips.
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Old 13th August 2018, 19:33   #17
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Originally Posted by deathwalkr View Post
And oops didn't see the link you had put up. How are those lights? Been thinking of buying something similar to that from Philips.
I put up a generic link from Amazon, I don't know which brand is actually installed in the new flat. I have not moved in yet.

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Indians raised up in the 80s and 90s were using the white light even before the white LEDs of 6500K.
Here is a lighting industry article from 1993, talking about various tube light options.

Look at the first paragraph in page 2. And the table at the bottom of page 4. The lowest color temperature available was 3000K and the highest was 5000K. This is from 4 different manufacturers.

Looks like then they had the sense not to create blinding lights.
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Old 14th August 2018, 15:07   #18
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

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Originally Posted by Samurai View Post

Looks like then they had the sense not to create blinding lights.
Will revert with observed data, but the white tubelights and CFLs used in offices cannot be <5500 K color. Because ... My past observations:

~ 2700K is yellow orange like 40-60W incandescent (warm CFLs and tubes are also available with same color but they appear more pure orange)
~ 3400K is yellowish like 100W incandescent / halogen
~ 4200K is white with yellowish cast something like extremely strong halogen (these LEDs are available as "natural white")
~ 5500K is the color of sunrays incident on white surface - should be known as the real natural white (which does have a tinge of yellow in it)
~ 6500K is the color of white surface on an overcast sky - this is "pure" white for most people

Any higher temperature and the white surface starts getting bluish tones.


The tubelights that I have encountered are definitely in the 6500K category.
Perhaps the reason why I have always hated them.
But as I said, I will revert with real observations.

Last edited by alpha1 : 14th August 2018 at 15:09.
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Old 14th August 2018, 18:07   #19
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

Here are some more:

https://www.fastcompany.com/90216977...adily-blind-us

https://medium.com/@caseorganic/why-...s-d992a352464b
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Old 17th August 2018, 12:09   #20
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

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Originally Posted by alpha1 View Post
Will revert with observed data, but the white tubelights and CFLs used in offices cannot be <5500 K color. Because ... My past observations:

~ 2700K is yellow orange like 40-60W incandescent (warm CFLs and tubes are also available with same color but they appear more pure orange)
~ 3400K is yellowish like 100W incandescent / halogen
~ 4200K is white with yellowish cast something like extremely strong halogen (these LEDs are available as "natural white")
~ 5500K is the color of sunrays incident on white surface - should be known as the real natural white (which does have a tinge of yellow in it)
~ 6500K is the color of white surface on an overcast sky - this is "pure" white for most people

Any higher temperature and the white surface starts getting bluish tones.


The tubelights that I have encountered are definitely in the 6500K category.
Perhaps the reason why I have always hated them.
But as I said, I will revert with real observations.
Checked and confirmed - the white tubes and CFLs in my office and my home are 6500K (some are 6400K)
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Old 20th August 2018, 17:21   #21
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

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Checked and confirmed - the white tubes and CFLs in my office and my home are 6500K (some are 6400K)
I too checked the old tubelights in my 18 year old home. Some are T12 and some are T8. Yes, they are all 6500K, the T12 being 40W and T8 being 36W.

So you were right, and I was wrong. But it still doesn't explain why the LED is lot harsher to look at compared to the tubelight. The lumen specs for the old tubelights are around 2400. That is higher than the LED bulbs in general. The 18W LED has a specs of 1800 lumens.

Could it be because the light source is spread across 4ft long tube, while the LED bulb is just 3-4 inches across. The light density at source is more than 10 times compared to the tubelight.

BTW, I just replaced a cool white (6500K) LED bulb with a warm white (3000K) LED bulb in my home office. I can finally look at the light without hurting my eyes. The room also feels warm and cozy. Wife was complaining about the harsh light for couple years, and now she is happy.
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Old 21st August 2018, 12:07   #22
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

I think it also has to do with the fact that a tubelight is a source of diffused light as the entire tube is filled with several inert gases. Unlike a focussed source of light in a regular LED bulb.

As a matter of fact, of late all manufacturers have started putting these white lights for not only cars but even two wheelers. I am not sure what kind of study was done before they were unleashed on the road. However, at least personally for me, this is highly disturbing. Even a vehicle behind me causes me to flinch with its white headlight reflecting off the inner mirror. I am seriously thinking whether to file a RTI on the MORTH.

Last edited by Zappo : 21st August 2018 at 12:10.
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Old 23rd August 2018, 16:11   #23
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

Quote:
BTW, I just replaced a cool white (6500K) LED bulb with a warm white (3000K) LED bulb in my home office. I can finally look at the light without hurting my eyes. The room also feels warm and cozy. Wife was complaining about the harsh light for couple years, and now she is happy.

Thankfully, I as well as my spouse prefer the warm tones in lighting. But I can imagine the plight of people who are stuck with people having preferences at opposite end of the spectrum (I know a few)

Quote:
Originally Posted by Samurai View Post
why the LED is lot harsher to look at compared to the tubelight.

Could it be because the light source is spread across 4ft long tube, while the LED bulb is just 3-4 inches across. The light density at source is more than 10 times compared to the tubelight.
Quote:
Originally Posted by Zappo View Post
I think it also has to do with the fact that a tubelight is a source of diffused light as the entire tube is filled with several inert gases. Unlike a focussed source of light in a regular LED bulb.
Well you both are right.
Tubes and CFLs have phosphor coating that converts the UV (or whatever spectrum generated internally) to the visible light. The phosphor coating diffuses the light.

Also the Tube / CFL lumens are spread over a higher square inch of space compared to LED.

LED emits light like a point source - it requires a proper diffuser to be pleasing to eye. Which means an opaque white film like white paper.


Quote:
I am seriously thinking whether to file a RTI on the MORTH.
Please do so. I am absolutely tired with these white light-sabers on the roads.
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Old 25th August 2018, 17:29   #24
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I have Crizal Prevencia blue light protector lenses - costs around Rs. 5,000. It is a totally clear lens - so visibility is as it should be:

Attachment 1789158

But at a different angle, it acquires a bluish tinge:
Does 5K includes the frame cost? I inquired few stores and they quoted between 3.3K-3.5K plus frame cost. I spend 8-10 hours a day in front of computer monitor and mobile phone. Do you suggest going for it?
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Old 25th August 2018, 20:15   #25
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Thanks to this thread, I bought 4000k LED tubelights. I would have kept using the older tubelights but they are getting more difficult to find and they don't work well in voltage fluctuations which are abundant in our rural setting.
The LED bulbs are 6500k which are currently installed and you can feel their sharpness even out of the corner of your eye. I am guessing most people went for these 6500k bulbs because lower kelvin bulbs reminded of older yellow bulbs which most people hated and chose tubelights over them.
A high quality diffuser can make a big difference in an LEDs throw and can even make a 6500k seem bearable but a 4000k seems to be the best compromise at the moment.
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Old 25th August 2018, 21:07   #26
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

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Originally Posted by Latheesh View Post
Does 5K includes the frame cost? I inquired few stores and they quoted between 3.3K-3.5K plus frame cost. I spend 8-10 hours a day in front of computer monitor and mobile phone. Do you suggest going for it?
Just for the lens and without frame cost. There are lots of add-ons to this lens, and I guess I opted for the "fully loaded" variant with all the checkboxes ticked!

Well, to be frank, it does not feel any different. But then, computer and smartphone display never used to bother me in the first place. Go for it if you trust the brand - hopefully it works as advertised.

Last edited by SmartCat : 25th August 2018 at 21:09.
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Old 25th August 2018, 21:24   #27
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Originally Posted by smartcat View Post
Just for the lens and without frame cost. There are lots of add-ons to this lens, and I guess I opted for the "fully loaded" variant with all the checkboxes ticked! .
Thanks. I checked few more stores and found that 3.9K is for normal plastic 1.56 one, and 4.9K for unbreakable Polycarbonate 1.59 variant. Discount offered are 10-15% and, Titan Eye Plus offers no discount.

Looks like I need to get my eyes checked before going for it. Result of sitting ~ 8 hours a day in front of computers last 17 years.

Last edited by Latheesh : 25th August 2018 at 21:26.
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Old 26th August 2018, 08:11   #28
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Originally Posted by smartcat View Post
Just for the lens and without frame cost. There are lots of add-ons to this lens, and I guess I opted for the "fully loaded" variant with all the checkboxes ticked!

Well, to be frank, it does not feel any different. But then, computer and smartphone display never used to bother me in the first place. Go for it if you trust the brand - hopefully it works as advertised.

It does have a slight yellowish tint, basically putting you into a permanent night mode of sorts. The reflection visible to another person, from your glasses are blue/purple in color.
I used the prevencia for 2 years on my last pair, and have now moved to a similar product from Carl Zeiss.
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Old 26th August 2018, 11:19   #29
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

Our bodies are trained to follow the circadian rhythm.. it is our own biological clock which uses the eyes and the light as a reference point. For example the eyes absorbing the sunlight during the day, makes the body realize that it is daytime and suitable energy is released autonomously to keep the body in peak condition. When the twilight of the dusk is seen by the eyes, the circadian rhythm knows that is is wind-down time and the body is prepped for sleeping by the release of hormones and natural neuro-chemicals (melatonin).

The blue/white like is a wave of light the eyes/body, does not recognize.. it messes with the circadian rhythm completely. It destroys sleep patterns and makes one feel tired, depressed (for no reason) and makes the body weaker (no sleep, no protein synthesis).

The finest examples are the birds and cats/dogs.. observe them and you know they wind down after dusk.. prepare for sleep and fall asleep a couple of hours after darkness.

I have a personal experience in this.. 4-5 years ago I decided to de-tox for 2 weeks by ignoring the computer/mobile fully. Only television was watched and I went for walks, played basketball and stayed outdoors as much as possible. I found that I slept very well at night, my eyes started to see much, much sharper than before (almost like a live 1080p) and I felt less stressful.

I've fallen victim to this mindless technology thanks to work and emails and excel sheets. Its making me miserable but I don't know how to exit this cycle of dependency. Believe me guys, this blue light is no theory, it harms.
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Old 26th August 2018, 15:53   #30
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Re: Blue light (smartphones, computers, TV, LED lights) accelerates blindness

Do we have some kind of a lens like crizal prevencia mentioned which can be used without any kind of prescription lenses. I have clear vision without the requirement of any power. But I have decent usage of the Laptop, CellPhone(which I have set to bluelight filteration) and driving as well.

We all know that other than just laptop and mobile, driving on the road with these glaring LEDs is another danger for our eyes.

So any pointers towards a Non-power clear lens which is good for working and driving, day and night?
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