Cities are swapping traditional light bulbs for more energy-efficient brighter LEDs. The rise of these blue LEDs are creating problems for our night sky and our health.
Not really, CRI is not dependent on color temperature; 2400K and 2700K incandescent bulbs all have CRI of 100. And, as you said, human brain is incredibly good at adopting to light color temperature. While I would not do color-critical work in candlelight, 2700K and 2400K bulbs are perfect for general late evening lighting and 3000K…3500K is very good for task lights. Higher than 4000K lights should not be a thing in domestic or public outdoor lighting, it’s just too harsh and uncozy.
You don’t need high lumens, either. As an extreme example, I’ve done plenty hiking (and patrolling during my military training) in starlight with no artificial light source—the eye is quite remarkable at adopting to darkness. The cities today are overly bright at nights, you could easily halve (or more) the lumen output and be absolutely fine. Even light distribution with no shadowy dark spots is way more useful than overly bright lights. Another personal anecdote, I live on 9th floor and I don’t need to turn on any lights when visiting bathroom at night; the light pollution from outside through curtains is enough to navigate around in my apartment.
Not really, CRI is not dependent on color temperature; 2400K and 2700K incandescent bulbs all have CRI of 100. And, as you said, human brain is incredibly good at adopting to light color temperature. While I would not do color-critical work in candlelight, 2700K and 2400K bulbs are perfect for general late evening lighting and 3000K…3500K is very good for task lights. Higher than 4000K lights should not be a thing in domestic or public outdoor lighting, it’s just too harsh and uncozy.
You don’t need high lumens, either. As an extreme example, I’ve done plenty hiking (and patrolling during my military training) in starlight with no artificial light source—the eye is quite remarkable at adopting to darkness. The cities today are overly bright at nights, you could easily halve (or more) the lumen output and be absolutely fine. Even light distribution with no shadowy dark spots is way more useful than overly bright lights. Another personal anecdote, I live on 9th floor and I don’t need to turn on any lights when visiting bathroom at night; the light pollution from outside through curtains is enough to navigate around in my apartment.