JoakimFlorence
Newly Enlightened
- Joined
- Jun 4, 2016
- Messages
- 137
I realise this has to do with fixed lighting, but thought it might be more appropriate to put it here.
I recently saw the parking lot in front of a local strip mall installed some new LED street lighting. What's interesting about these LED street lights is they have an obvious yellow-green color cast to them. They're not all yellow-green in color, the light is kind of whitish too.
The light has an interesting feel. It feels a little "softer" and warmer, like high pressure sodium street lamps, but still a little industrial and sickly, off-color.
It's as if someone took some LED phosphor intended for 5000K and covered them over the dye with a thickness normally used for 3000K LEDs. And I am talking lower 70 CRI phosphor here, the type normally used for streetlamps.
I got right under the lights too, because I know sometimes with these cheap LED streetlamps the exact color of the light can vary with the angle and if you're standing right under it the light will be whiter than it looks viewed from a distance, but that was not the case here, the color of the light was still the same standing right under it and looking up.
I'm not sure exactly why these streetlamps were tinted, but could put forth a few guesses. It could have just been low quality. Perhaps this was an intentional strategy for maximum lumen output. With a greater portion of the blue light converted into yellow-green light through the phosphor, the lumen efficiency would have been raised (since the eye has several times higher sensitivity to green light than to blue light). Light quality probably wasn't seen as mattering so much since these were just replacing sodium streetlamps.
Or maybe the lights were designed for reduced glare, by allowing less blue light through the phosphor. I could still see blue color objects under the light, but these blue colored objects seemed kind of dull in blue coloration.
I think I kind of preferred these streetlamps over the regular 5000K streetlamps. It feels softer and less glaring. There were 5000K streetlamps lining the street right in front of the parking lot so I could see both side by side. The normal streetlamps seemed a light more bluish and magenta-tinted in comparison.
I recently saw the parking lot in front of a local strip mall installed some new LED street lighting. What's interesting about these LED street lights is they have an obvious yellow-green color cast to them. They're not all yellow-green in color, the light is kind of whitish too.
The light has an interesting feel. It feels a little "softer" and warmer, like high pressure sodium street lamps, but still a little industrial and sickly, off-color.
It's as if someone took some LED phosphor intended for 5000K and covered them over the dye with a thickness normally used for 3000K LEDs. And I am talking lower 70 CRI phosphor here, the type normally used for streetlamps.
I got right under the lights too, because I know sometimes with these cheap LED streetlamps the exact color of the light can vary with the angle and if you're standing right under it the light will be whiter than it looks viewed from a distance, but that was not the case here, the color of the light was still the same standing right under it and looking up.
I'm not sure exactly why these streetlamps were tinted, but could put forth a few guesses. It could have just been low quality. Perhaps this was an intentional strategy for maximum lumen output. With a greater portion of the blue light converted into yellow-green light through the phosphor, the lumen efficiency would have been raised (since the eye has several times higher sensitivity to green light than to blue light). Light quality probably wasn't seen as mattering so much since these were just replacing sodium streetlamps.
Or maybe the lights were designed for reduced glare, by allowing less blue light through the phosphor. I could still see blue color objects under the light, but these blue colored objects seemed kind of dull in blue coloration.
I think I kind of preferred these streetlamps over the regular 5000K streetlamps. It feels softer and less glaring. There were 5000K streetlamps lining the street right in front of the parking lot so I could see both side by side. The normal streetlamps seemed a light more bluish and magenta-tinted in comparison.