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Are LEDs aggressive to the eyes even if you manage to get them to have the same colour as ordinary light bulbs?

Noseshine 10y ago
You mean spectrum - a big difference. "Color" means little or nothing. Very different spectra can have the same "color". I highly recommend reading through this, very educational about how complicated "vision" really is: http://webvision.med.utah.edu/book/part-vii-color-vision/color-vision/ http://webvision.med.utah.edu/book/part-vii-color-vision/col... It's a long read but well worth it. "Color" is something your brain creates, it's not "physical". Frequencies of light of course are a (the) major input, but it's not in any way a straightforward 1:1 one.
- Bromskloss 10y ago
  I mean colour, not spectrum. I don't expect, or at least don't count on, LEDs to reproduce a black-body spectrum. I recognise that two light sources with the same colour, but different spectra, might give different results when reflected off things. Is that what you had in mind?
  - dr_zoidberg 10y ago
    I think he meant that 2 things having the same colour, but different spectrum, can have different effects on your vision (and body?). The example that most easily comes to my mind is a LED screen representing a yellow colour, versus a lemon under the sun. Shame he didn't elaborate, it seemed to be an interesting topic.
  - Noseshine 10y ago
    Every light source produces a spectrum - even a laser, albeit only small one. Have a look at this link: http://www.soundandvision.com/content/led-vs-cfl-bulbs-color-temp-light-spectrum-and-more http://www.soundandvision.com/content/led-vs-cfl-bulbs-color... As you can see a lot of LEDs have quite a lot of blue. Which is exactly what is responsible for synchronizing your own "clock": http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831986/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831986/ > Not only does light reset the human circadian rhythm, but the same blue > light that has the strongest impact on dinoflagellates has equal power > to reset our own clocks — although most visible wavelengths can reset > the clock, the blues do the job with the greatest efficiency. Which is the whole reason f.lux became so popular.

You mean spectrum - a big difference. "Color" means little or nothing. Very different spectra can have the same "color". I highly recommend reading through this, very educational about how complicated "vision" really is: http://webvision.med.utah.edu/book/part-vii-color-vision/color-vision/ http://webvision.med.utah.edu/book/part-vii-color-vision/col... It's a long read but well worth it. "Color" is something your brain creates, it's not "physical". Frequencies of light of course are a (the) major input, but it's not in any way a straightforward 1:1 one.

Bromskloss 10y ago
I mean colour, not spectrum. I don't expect, or at least don't count on, LEDs to reproduce a black-body spectrum. I recognise that two light sources with the same colour, but different spectra, might give different results when reflected off things. Is that what you had in mind?
- dr_zoidberg 10y ago
  I think he meant that 2 things having the same colour, but different spectrum, can have different effects on your vision (and body?). The example that most easily comes to my mind is a LED screen representing a yellow colour, versus a lemon under the sun. Shame he didn't elaborate, it seemed to be an interesting topic.
- Noseshine 10y ago
  Every light source produces a spectrum - even a laser, albeit only small one. Have a look at this link: http://www.soundandvision.com/content/led-vs-cfl-bulbs-color-temp-light-spectrum-and-more http://www.soundandvision.com/content/led-vs-cfl-bulbs-color... As you can see a lot of LEDs have quite a lot of blue. Which is exactly what is responsible for synchronizing your own "clock": http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831986/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831986/ > Not only does light reset the human circadian rhythm, but the same blue > light that has the strongest impact on dinoflagellates has equal power > to reset our own clocks — although most visible wavelengths can reset > the clock, the blues do the job with the greatest efficiency. Which is the whole reason f.lux became so popular.