7 ms·

I recall that a paper published by Oxford in a journal related to gerontology claimed that blue light accelerated aging of the retina. If I understand correctly

I recall that a paper published by Oxford in a journal related to gerontology claimed that blue light accelerated aging of the retina. If I understand correctly, this article doesn't counter that claim outright, it just didn't find that risk with the low intensity of blue light coming from a typical monitor. Tangentially related, that same Oxford paper (sorry I don't have a link and no longer have access to the paper) did however claim that light generated by red LEDs with sufficient intensity to leave a significant persistence effect after 3 minutes of exposure can reverse aging and damage in subjects over 40 years old although the sample size was just a few dozen people IIRC. It does so because somehow the retina's mitochondrial function is improved by light in the 650nm to 1000nm range. Continuing on this tangent, I am 50 and have been exposing my eyes to red light for 3 minutes a day for many months and feel like my night vision has been restored. If I wake up in the middle of the night I used to see gray noise and now I can see darker black with better contrast. But I may be kidding myself.

toomuchtodo 5y ago
https://academic.oup.com/biomedgerontology/article/75/9/e49/5863431 https://academic.oup.com/biomedgerontology/article/75/9/e49/... TLDR Brief 3 minute daily exposures to 670 nm (energies at the cornea were approximately 40 mW/cm2) for 2 weeks can significantly improve retinal function in those over approximately 40 years of age Edit: 670 nm is deep red light
- jml7c5 5y ago
  670 nm is red light, isn't it?
- andrew_ 5y ago
  how does one expose their eyes to light in that spectrum safely?
  - copperx 5y ago
    I do not understand the assumptions behind this question. Can you clarify what you mean?
    - baq 5y ago
      Is a red bulb enough or do you need a 670nm laser?
      - flyinglizard 5y ago
        For the love of all that’s dear in this world, please don’t use a laser for that. If you’re in a DIY mood, you can easily pick LEDs around that wavelength and they would generate more than enough light to even cause damage (if close enough).
      - tlrobinson 5y ago
        I hope this was a joke. Don’t shine lasers in your eyes. https://en.wikipedia.org/wiki/Laser_safety https://en.wikipedia.org/wiki/Laser_safety
    - andrew_ 5y ago
      what assumptions? it was an honest question.
  - webmobdev 5y ago
    The safest way to do this is to step out in daylight when the sun is bright. Take a brief walk. You will also get a boost of Vitamin D that will cheer you up. Interestingly, in Yoga there is a pose called surya namaskar (salutation to the sun) that is supposed to be done early morning when the sun rises.
    - andrew_ 5y ago
      Can I assume you mean without sunglasses on? Living in FL I wear sunglasses religiously, but am out in the sun daily.
      - webmobdev 5y ago
        Yes, at least for sometime daily, but not in blinding sunlight that can hurt your eyes.
- hbarka 5y ago
  Where do you find this sort of light and how do you ergonomically do this?
  - mjard 5y ago
    I'd imagine your eyelids and the sun.
  - logicchop 5y ago
    I picked up a great 670nm light from here: https://redlightman.com/ https://redlightman.com/
    - aksss 5y ago
      Of course there’s a redlightman.com, but I am a bit surprised at the cost of these things. Is there something special about these “therapy lights” that a guy with a soldering iron and a handful of cheap 670nm LEDs wouldn’t be getting? I mean, the price of these finished products compared to my perception of the component costs is rather astounding.
      - 14 5y ago
        This is the absurd reality anyone interested in led growing faces. And the saddest part is the uneducated fall for the many led scams out there. Many will advertise as 1000watts but then when you read the fine print they will say equivalent to 1000w. Or another good one they will name the model of the light “1000w LED Light” 1000w being the model of the light not the wattage. On top of it all many of these cheap lights are being sold for much more then they are truly worth to anyone. There are some reputable sellers who actually advertise the actual wattage used by lights but then you are really paying a premium. Like you said tho the reality is if you can solder these are easy to make. And if you live in the US you are really sitting pretty because all the parts are so cheap compared to me in Canada where I have to ship every part from the US. For about $600-$800US you can make a light that retails for closer to $2k. Here is a very informative sight which goes over how to make several different led grow light builds ranging from 2x2 foot grow tent to an led for a 5x5. https://ledgardener.com/diy-led-strip-build-designs-samsung-bridgelux/ https://ledgardener.com/diy-led-strip-build-designs-samsung-...
- DantesKite 5y ago
  Very interesting. Thank you. Red light is also just fun to be in. It has a different atmospheric mood.
  - blackhaz 5y ago
    I have a gaming rig with two big front fans with red LEDs. I can swear my eyesight and mood improves just by staring a few minutes on them.
- gingerlime 5y ago
  I wonder about presbyopia though. Would imagine that’s the holy grail of age-related vision decay? anyone knows of any promising research in this area?
  - ncmncm 5y ago
    I used reading glasses for years. Then I started drinking a pint of kombucha, most days. I got my accommodation back, no more reading glasses! Other improvements too, e.g. blood pressure, skin elasticity. I can't think of anything else to attribute the improvement to. I would never have guessed anything would help. (No guarantees, but would welcome other reports, positive or negative.) This is one of those "anecdotal" things where you might as well, because there is only potential upside, plus tasty hydration, no down. Like getting your Tdap booster (free at the drug store), because why not? A pint of kombucha runs US$2.50-$4 at the supermarket. But I brew mine for <$0.20.
    - jtwaleson 5y ago
      Ok, that sounds kind of whacky but very intriguing. Can I ask what age you are and if you measured your current accommodation power (like: how many diopters can you accommodate now)?
      - ncmncm 5y ago
        Old enough to notice skin elasticity. My reading glasses were +1.5. I still use them for extra-fine print, so there are limits.
    - beebeepka 5y ago
      Is your brew carbonated? The stuff at the grocery store says it's naturally carbonated but I have no idea how it all works
      - PeterisP 5y ago
        Kombucha includes also yeast which metabolizes sugars and releases CO2 so it has some natural carbonation like e.g. beer does.
easygenes 5y ago
As any skilled visual astronomy observer will tell you… you can train your eyes. Part of this is acknowledging that your night vision is best off-center and learning to foveate in a way which takes advantage of that, but a degree of it is also in just patient noticing. Skilled observers will pick up details in the sky people decades younger than them would miss, with the same view.
- DaftDank 5y ago
  I've noticed I can see the Milky Way best when I observe off-center. As soon as I try to focus directly on it, it's not as clear. Bortle sky 4 probably, SQM about 21
- sandworm101 5y ago
  That difference between center and peripheral vision isn't a defect. It has served us well for thousands of years. Center vision is for hunting, for tracking a target you want to chase/kill. Off-center vision is for noticing stuff in the bushes trying to kill you. So off-center vision is better at night and for detecting movement. That kept us away from the lions. Our acute center vision is tuned for daylight. It helped kill those lions when it was our turn to hide in the bushes.
- bregma 5y ago
  Foveate. That's a new verb to me. From the context I take it to mean to direct the subject of one's visual attention to something else other than what one is consciously trying too. I guess it's like ethmoidating a perfume, or palatatating the mouthfeel of a fine wine, or phalangating rough textures. Glad to see the language is still alive.
- dotancohen 5y ago
  The best way to show this to non-observers is to show them the Pleiades. Most people can clearly identify a blobby cloud, but it disappears for them when they look right at it. You have to really look at it for a minute or two for the eye to pick up on it when focusing on it.
Lammy 5y ago
> But I may be kidding myself. Luckily there's no requirement to justify a personal preference. I hate staring at LEDs/monitors without a warm filter even if it isn't hurting my eyes.
- smoldesu 5y ago
  Have you considered alternatively switching to a warmer colorscheme like Gruvbox in your main apps? That way only the UI elements are warm while your video and other important windows remain unafflicted.
  - Lammy 5y ago
    It's not just displays since LED is so pervasive for all types of lighting these days. The tail lights on modern cars are the absolute worst offenders to me when I'm driving at night. Wearing my yellow-tinted glasses is the only way to make it bearable.
- acjohnson55 5y ago
  Same here. Can't go back, won't go back.
- bscphil 5y ago
  Most screens are too blue. Not in a personal preference sense, in an objective sense. That's why monitor profiling and color correction are important. Similar to you, I find it grating to use most screens for a long period of time, but I think the better solution to that problem is just to profile your screens.
  - ketzo 5y ago
    Our of curiosity, how would I do that? Or is this just something I should look up?
    - baq 5y ago
      The easiest way is to pay a professional. Hardware required to properly calibrate a display is too expensive to make any sense to buy it unless you don’t care about money. You won’t get great results by downloading profiles from the internet because every unit is different coming out of factory.
the_d3f4ult 5y ago
|I recall that a paper published by Oxford in a journal related to gerontology claimed that blue light accelerated aging of the |retina. If I understand correctly, this article doesn't counter that claim outright, it just didn't find that risk with the low | |intensity of blue light coming from a typical monitor. I don't know the paper you're referring to but I'd be curious to read it. The most commonly espoused hypothesis that I hear is that increased exposure to blue light increases the rate of progression of age-related macular degeneration. Macular degeneration is essentially an accumulation of the byproducts of photoreceptor recycling in the retina. Certain people in the business of selling glasses latched onto this idea and it's spawned a cottage industry of snake oil salesman peddling dubiously effective blue-light filtering glasses and other gizmos. As far as I am aware there is no evidence that blue light actually increases the rate of progression of AMD in humans, and there's some compelling evidence that it has no effect. https://www.aaojournal.org/article/S0161-6420(20)30727-2/fulltext https://www.aaojournal.org/article/S0161-6420(20)30727-2/ful...
- GhettoComputers 5y ago
  The brightness of blue light matters. Its like measuring how radioactive a banana is and worrying about it.
- copperx 5y ago
  I just remembered the dark sunglasses that some senior people wear that look almost like goggles, where the sides are also covered. I have never asked what are those for, but I imagine it's for preventing degeneration.
  - the_d3f4ult 5y ago
    They're designed to fit over regular prescription glasses and block light coming in peripherally. We give them to everyone after eye surgery. They're not specifically designed to prevent macular degeneration. Try them sometime, they work incredibly well. I wear them now when driving.
lakeeffect 5y ago
What do you use for your source of light?
lotsofpulp 5y ago
This is a 2018 HN thread discussing it: https://news.ycombinator.com/item?id=17724995 https://news.ycombinator.com/item?id=17724995
alin23 5y ago
I always thought that staring at monitors with blinding brightness is what causes retinal damage, not just blue light specifically. That's one of the reasons I created Lunar (https://lunar.fyi https://lunar.fyi): because having to lower the brightness of the monitor throughout the day, using its hard to find buttons, was such an annoying endeavor. I’ve always used f.lux and now Night Shift simply because I like warm colors. I have all LED bulbs and strips in my house adapt automatically to <3000K after sunset just because it gives me a sense of warmth and coziness. But now, thanks to your comment I stumbled onto the “intense red light” cult. I had no idea about this effect, I thought all intense light is bad for the eyes. But I hope someone tries to reproduce this study. Usually, bold claims like these can be the effect of cumulative small errors in the study process.
- nebula8804 5y ago
  Have you heard of these new e-Ink PC monitors coming out of China? They seem like a promising niche use case for computing without the eye strain. [1]: https://www.amazon.com/Dasung-Paperlike-Front-Light-Touch-Monitor/dp/B07SKS6CS7 https://www.amazon.com/Dasung-Paperlike-Front-Light-Touch-Mo...
  - krrrh 5y ago
    Wow. If anyone else found this intriguing and wasn’t aware of this this product category was emerging, their demo video is pretty impressive [0]. I’m balking at $1100 for 13.3”, but if they could get the price down a bit these would be great second screens for writing and email. I’d need minimal color support for coding, but that would also sell like hotcakes. Edit: wow, they have a 25” monitor set to retail for $3k. Come on early adopters, get this price down for the rest of us! [0] https://m.youtube.com/watch?v=vnUACe8Bsyg https://m.youtube.com/watch?v=vnUACe8Bsyg
    - KingMachiavelli 5y ago
      My understanding is that the cost of sink is due to the patent holder keeping licensing costs high which keeps it niche. i.e e-ink is expensive so it is rare so it is expensive. TBH at this point I have no idea why you need e-ink out side of low power situations. Quality VA panels have great contrast and viewing angles. OLED is even better. At the prices e-ink displays are, a OLED screen would be more versatile and probably just as little eye strain (just use low brightness).
nebula8804 5y ago
>Continuing on this tangent, I am 50 and have been exposing my eyes to red light for 3 minutes a day for many months and feel like my night vision has been restored. If I wake up in the middle of the night I used to see gray noise and now I can see darker black with better contrast. But I may be kidding myself. Maybe you can measure this with some placard on a wall with different shades of black strips (kinda like those old TV calibration screens) where you can see some of the black strips but not others and as time goes on measure if you can improve your visibility into it. [1]:https://www.audioholics.com/home-theater-calibration/hdtv-calibration/calibration3.png/image https://www.audioholics.com/home-theater-calibration/hdtv-ca... Maybe some other chart like this might work better.
lugged 5y ago
What kind of red light are you using for this? Would just getting a red lamp for the office be enough for this?

toomuchtodo 5y ago

https://academic.oup.com/biomedgerontology/article/75/9/e49/5863431 https://academic.oup.com/biomedgerontology/article/75/9/e49/... TLDR Brief 3 minute daily exposures to 670 nm (energies at the cornea were approximately 40 mW/cm2) for 2 weeks can significantly improve retinal function in those over approximately 40 years of age Edit: 670 nm is deep red light

jml7c5 5y ago
670 nm is red light, isn't it?
andrew_ 5y ago
how does one expose their eyes to light in that spectrum safely?
- copperx 5y ago
  I do not understand the assumptions behind this question. Can you clarify what you mean?
  - baq 5y ago
    Is a red bulb enough or do you need a 670nm laser?
    - flyinglizard 5y ago
      For the love of all that’s dear in this world, please don’t use a laser for that. If you’re in a DIY mood, you can easily pick LEDs around that wavelength and they would generate more than enough light to even cause damage (if close enough).
    - tlrobinson 5y ago
      I hope this was a joke. Don’t shine lasers in your eyes. https://en.wikipedia.org/wiki/Laser_safety https://en.wikipedia.org/wiki/Laser_safety
  - andrew_ 5y ago
    what assumptions? it was an honest question.
- webmobdev 5y ago
  The safest way to do this is to step out in daylight when the sun is bright. Take a brief walk. You will also get a boost of Vitamin D that will cheer you up. Interestingly, in Yoga there is a pose called surya namaskar (salutation to the sun) that is supposed to be done early morning when the sun rises.
  - andrew_ 5y ago
    Can I assume you mean without sunglasses on? Living in FL I wear sunglasses religiously, but am out in the sun daily.
    - webmobdev 5y ago
      Yes, at least for sometime daily, but not in blinding sunlight that can hurt your eyes.
hbarka 5y ago
Where do you find this sort of light and how do you ergonomically do this?
- mjard 5y ago
  I'd imagine your eyelids and the sun.
- logicchop 5y ago
  I picked up a great 670nm light from here: https://redlightman.com/ https://redlightman.com/
  - aksss 5y ago
    Of course there’s a redlightman.com, but I am a bit surprised at the cost of these things. Is there something special about these “therapy lights” that a guy with a soldering iron and a handful of cheap 670nm LEDs wouldn’t be getting? I mean, the price of these finished products compared to my perception of the component costs is rather astounding.
    - 14 5y ago
      This is the absurd reality anyone interested in led growing faces. And the saddest part is the uneducated fall for the many led scams out there. Many will advertise as 1000watts but then when you read the fine print they will say equivalent to 1000w. Or another good one they will name the model of the light “1000w LED Light” 1000w being the model of the light not the wattage. On top of it all many of these cheap lights are being sold for much more then they are truly worth to anyone. There are some reputable sellers who actually advertise the actual wattage used by lights but then you are really paying a premium. Like you said tho the reality is if you can solder these are easy to make. And if you live in the US you are really sitting pretty because all the parts are so cheap compared to me in Canada where I have to ship every part from the US. For about $600-$800US you can make a light that retails for closer to $2k. Here is a very informative sight which goes over how to make several different led grow light builds ranging from 2x2 foot grow tent to an led for a 5x5. https://ledgardener.com/diy-led-strip-build-designs-samsung-bridgelux/ https://ledgardener.com/diy-led-strip-build-designs-samsung-...
DantesKite 5y ago
Very interesting. Thank you. Red light is also just fun to be in. It has a different atmospheric mood.
- blackhaz 5y ago
  I have a gaming rig with two big front fans with red LEDs. I can swear my eyesight and mood improves just by staring a few minutes on them.
gingerlime 5y ago
I wonder about presbyopia though. Would imagine that’s the holy grail of age-related vision decay? anyone knows of any promising research in this area?
- ncmncm 5y ago
  I used reading glasses for years. Then I started drinking a pint of kombucha, most days. I got my accommodation back, no more reading glasses! Other improvements too, e.g. blood pressure, skin elasticity. I can't think of anything else to attribute the improvement to. I would never have guessed anything would help. (No guarantees, but would welcome other reports, positive or negative.) This is one of those "anecdotal" things where you might as well, because there is only potential upside, plus tasty hydration, no down. Like getting your Tdap booster (free at the drug store), because why not? A pint of kombucha runs US$2.50-$4 at the supermarket. But I brew mine for <$0.20.
  - jtwaleson 5y ago
    Ok, that sounds kind of whacky but very intriguing. Can I ask what age you are and if you measured your current accommodation power (like: how many diopters can you accommodate now)?
    - ncmncm 5y ago
      Old enough to notice skin elasticity. My reading glasses were +1.5. I still use them for extra-fine print, so there are limits.
  - beebeepka 5y ago
    Is your brew carbonated? The stuff at the grocery store says it's naturally carbonated but I have no idea how it all works
    - PeterisP 5y ago
      Kombucha includes also yeast which metabolizes sugars and releases CO2 so it has some natural carbonation like e.g. beer does.

easygenes 5y ago

As any skilled visual astronomy observer will tell you… you can train your eyes. Part of this is acknowledging that your night vision is best off-center and learning to foveate in a way which takes advantage of that, but a degree of it is also in just patient noticing. Skilled observers will pick up details in the sky people decades younger than them would miss, with the same view.

DaftDank 5y ago
I've noticed I can see the Milky Way best when I observe off-center. As soon as I try to focus directly on it, it's not as clear. Bortle sky 4 probably, SQM about 21
sandworm101 5y ago
That difference between center and peripheral vision isn't a defect. It has served us well for thousands of years. Center vision is for hunting, for tracking a target you want to chase/kill. Off-center vision is for noticing stuff in the bushes trying to kill you. So off-center vision is better at night and for detecting movement. That kept us away from the lions. Our acute center vision is tuned for daylight. It helped kill those lions when it was our turn to hide in the bushes.
bregma 5y ago
Foveate. That's a new verb to me. From the context I take it to mean to direct the subject of one's visual attention to something else other than what one is consciously trying too. I guess it's like ethmoidating a perfume, or palatatating the mouthfeel of a fine wine, or phalangating rough textures. Glad to see the language is still alive.
dotancohen 5y ago
The best way to show this to non-observers is to show them the Pleiades. Most people can clearly identify a blobby cloud, but it disappears for them when they look right at it. You have to really look at it for a minute or two for the eye to pick up on it when focusing on it.

Lammy 5y ago

> But I may be kidding myself. Luckily there's no requirement to justify a personal preference. I hate staring at LEDs/monitors without a warm filter even if it isn't hurting my eyes.

smoldesu 5y ago
Have you considered alternatively switching to a warmer colorscheme like Gruvbox in your main apps? That way only the UI elements are warm while your video and other important windows remain unafflicted.
- Lammy 5y ago
  It's not just displays since LED is so pervasive for all types of lighting these days. The tail lights on modern cars are the absolute worst offenders to me when I'm driving at night. Wearing my yellow-tinted glasses is the only way to make it bearable.
acjohnson55 5y ago
Same here. Can't go back, won't go back.
bscphil 5y ago
Most screens are too blue. Not in a personal preference sense, in an objective sense. That's why monitor profiling and color correction are important. Similar to you, I find it grating to use most screens for a long period of time, but I think the better solution to that problem is just to profile your screens.
- ketzo 5y ago
  Our of curiosity, how would I do that? Or is this just something I should look up?
  - baq 5y ago
    The easiest way is to pay a professional. Hardware required to properly calibrate a display is too expensive to make any sense to buy it unless you don’t care about money. You won’t get great results by downloading profiles from the internet because every unit is different coming out of factory.

the_d3f4ult 5y ago

|I recall that a paper published by Oxford in a journal related to gerontology claimed that blue light accelerated aging of the |retina. If I understand correctly, this article doesn't counter that claim outright, it just didn't find that risk with the low | |intensity of blue light coming from a typical monitor. I don't know the paper you're referring to but I'd be curious to read it. The most commonly espoused hypothesis that I hear is that increased exposure to blue light increases the rate of progression of age-related macular degeneration. Macular degeneration is essentially an accumulation of the byproducts of photoreceptor recycling in the retina. Certain people in the business of selling glasses latched onto this idea and it's spawned a cottage industry of snake oil salesman peddling dubiously effective blue-light filtering glasses and other gizmos. As far as I am aware there is no evidence that blue light actually increases the rate of progression of AMD in humans, and there's some compelling evidence that it has no effect. https://www.aaojournal.org/article/S0161-6420(20)30727-2/fulltext https://www.aaojournal.org/article/S0161-6420(20)30727-2/ful...

GhettoComputers 5y ago
The brightness of blue light matters. Its like measuring how radioactive a banana is and worrying about it.
copperx 5y ago
I just remembered the dark sunglasses that some senior people wear that look almost like goggles, where the sides are also covered. I have never asked what are those for, but I imagine it's for preventing degeneration.
- the_d3f4ult 5y ago
  They're designed to fit over regular prescription glasses and block light coming in peripherally. We give them to everyone after eye surgery. They're not specifically designed to prevent macular degeneration. Try them sometime, they work incredibly well. I wear them now when driving.

lakeeffect 5y ago

What do you use for your source of light?

lotsofpulp 5y ago

This is a 2018 HN thread discussing it: https://news.ycombinator.com/item?id=17724995 https://news.ycombinator.com/item?id=17724995

alin23 5y ago

I always thought that staring at monitors with blinding brightness is what causes retinal damage, not just blue light specifically. That's one of the reasons I created Lunar (https://lunar.fyi https://lunar.fyi): because having to lower the brightness of the monitor throughout the day, using its hard to find buttons, was such an annoying endeavor. I’ve always used f.lux and now Night Shift simply because I like warm colors. I have all LED bulbs and strips in my house adapt automatically to <3000K after sunset just because it gives me a sense of warmth and coziness. But now, thanks to your comment I stumbled onto the “intense red light” cult. I had no idea about this effect, I thought all intense light is bad for the eyes. But I hope someone tries to reproduce this study. Usually, bold claims like these can be the effect of cumulative small errors in the study process.

nebula8804 5y ago
Have you heard of these new e-Ink PC monitors coming out of China? They seem like a promising niche use case for computing without the eye strain. [1]: https://www.amazon.com/Dasung-Paperlike-Front-Light-Touch-Monitor/dp/B07SKS6CS7 https://www.amazon.com/Dasung-Paperlike-Front-Light-Touch-Mo...
- krrrh 5y ago
  Wow. If anyone else found this intriguing and wasn’t aware of this this product category was emerging, their demo video is pretty impressive [0]. I’m balking at $1100 for 13.3”, but if they could get the price down a bit these would be great second screens for writing and email. I’d need minimal color support for coding, but that would also sell like hotcakes. Edit: wow, they have a 25” monitor set to retail for $3k. Come on early adopters, get this price down for the rest of us! [0] https://m.youtube.com/watch?v=vnUACe8Bsyg https://m.youtube.com/watch?v=vnUACe8Bsyg
  - KingMachiavelli 5y ago
    My understanding is that the cost of sink is due to the patent holder keeping licensing costs high which keeps it niche. i.e e-ink is expensive so it is rare so it is expensive. TBH at this point I have no idea why you need e-ink out side of low power situations. Quality VA panels have great contrast and viewing angles. OLED is even better. At the prices e-ink displays are, a OLED screen would be more versatile and probably just as little eye strain (just use low brightness).

nebula8804 5y ago

>Continuing on this tangent, I am 50 and have been exposing my eyes to red light for 3 minutes a day for many months and feel like my night vision has been restored. If I wake up in the middle of the night I used to see gray noise and now I can see darker black with better contrast. But I may be kidding myself. Maybe you can measure this with some placard on a wall with different shades of black strips (kinda like those old TV calibration screens) where you can see some of the black strips but not others and as time goes on measure if you can improve your visibility into it. [1]:https://www.audioholics.com/home-theater-calibration/hdtv-calibration/calibration3.png/image https://www.audioholics.com/home-theater-calibration/hdtv-ca... Maybe some other chart like this might work better.

lugged 5y ago

What kind of red light are you using for this? Would just getting a red lamp for the office be enough for this?