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I work at an architectural lighting manufacturer, and yes, they definitely are. It killed incandescent/halogen first, then CFL. Metal halide (especially high w

I work at an architectural lighting manufacturer, and yes, they definitely are. It killed incandescent/halogen first, then CFL. Metal halide (especially high wattage) and linear fluorescent are still hanging on by a thread, but everybody in the industry acknowledges that they're on the way out. When I was in college (class of 2012) LED lighting was on the rise but the industry imagined they would take over much more slowly than what actually happened. We were still taking about CFLs as something that might come up more than once after we graduated.

hammock 9y ago
And at the same time, lots of (anec?)data coming out that LEDs have adverse health effects
- danmaz74 9y ago
  Example?
  - hammock 9y ago
    http://www.ledsmagazine.com/articles/2010/11/light-and-human-health-led-risks-highlighted.html http://www.ledsmagazine.com/articles/2010/11/light-and-human... http://www.cnn.com/2016/06/21/health/led-streetlights-ama/index.html http://www.cnn.com/2016/06/21/health/led-streetlights-ama/in...
    - Retric 9y ago
      That has little to do with LED's just a subset of cheap LED's.
      - wlesieutre 9y ago
        Pretty much all white LEDs are going to have high blue content. It goes back to how they work, these are actually phosphor converted blue LEDs where they pump out a ton of blue light and then use a phosphor layer to absorb and re-emit some of it at other wavelengths. See spectral distributions here: http://cdn2.goughlui.com/wp-content/uploads/2013/06/spectraldist.gif http://cdn2.goughlui.com/wp-content/uploads/2013/06/spectral... Even down at 2700K (blue line, "warm white") there's a substantial blue spike over on the left. The LEDs being used in most streetlights are cool white, probably 4000K+, definitely a lot of blue in that. There are high CRI LEDs available (Color Rendering Index - at warm colors it basically means "how similar do colors look under this vs under incandescent"), but they're much less efficient in terms of how much light you get per watt, and they tend to be a pretty niche product for lighting stuff where reds are important (brick walls, fruit, art, etc). Still some blue in that, but much less. https://www.yujiintl.com/img/graphics/warm-white-high-cri.png https://www.yujiintl.com/img/graphics/warm-white-high-cri.pn... As to health effects, from what I've heard the jury is still out, but there's a definite push toward "tunable white" in the industry. Whether anyone actually wants to pay for that when it comes time to choose between that or the cheaper fixed color temperature that we've been doing forever, things are less certain...
        Retric 9y ago
        I don't disagree with what your saying, but... LED's don't produce light from heat so they don't really correspond color temperature. They can fake it, but the current approach produces blue at higher efficiency than yellow. Thus upping the yellow content results in lower brightness and lower 'efficiency' for the same device or identical brightness and higher costs. However, producing a lot of blue light is often sub optimal so you need a consumer willing to make that trade-off instead of just seeing white/cost/brightness and assuming that's the whole story. Thus, cheap really does mean more blue.
        wlesieutre 9y ago
        You're correct that LEDs aren't actually producing light like a hot black body radiator, but we still measure their shade of white using that scale as a reference. This is called the "correlated color temperature," which you'll almost always see abbreviated to CCT. It's not "this light was produced by a black body radiator at 5000K", it's "this light is perceived by the human eye as the same color as a 5000K black body radiator. Where does the human-perceived color fall on the Plankian locus? https://en.wikipedia.org/wiki/Planckian_locus https://en.wikipedia.org/wiki/Planckian_locus As far as cheapness, yes and no. The swimming pools that I've designed tend toward the more blueish whites and low CRI because they have a light level target to hit and that's the cheapest way to do it. With the exception of some small residential pools, they aren't trying to make a warm cozy feeling, they just want it to be bright enough to meet the requirements for safety / code / IES recommendations / NCAA requirements, etc. But a lot of lighting isn't done that way where you're determining the layout and quantity of lights to hit a target level at lowest cost. It's much more common that you pick the color temperature that you want it to look like and you buy that regardless of the exact light output. LED bulbs at the store have a Lighting Facts label that tells you the color temperature and how bright it is, and the different CCTs of a given brand bulb will cost the same. Yes, you get more light out of the more blue one, but when you're getting bulbs for you're house you'd never say "Get the 4000K version. It's an extra 100 lumens, so we can light the house with 17 of them instead 18 and save a few bucks." Interestingly there are cultural conventions to this too. In the US it's much more common to see the warmer color temperatures in homes and even in offices. In Asia and India you'll encounter a lot more blue.
criddell 9y ago
Maybe you can explain something for me. I installed an IOT dimmer to control my bathroom lights which are dimmable LED bulbs. It works, except for one super annoying thing: when I turn them on, it flashes first at full brightness before going to the correct setting. It's so bright, it almost feels like a camera flash. The dimmer is a Lutron Caseta dimmer and it works nicely with the Echo and Apple Home.
- deleted 9y ago
  [deleted]
- akx 9y ago
  I have LED lighting in my bathroom, controlled by a non-IOT but remote-controllable dimmer, and it does not exhibit that behavior, so I'd say it's just a buggy dimmer.
- wlesieutre 9y ago
  LED dimming is a compatibility mess. Most commercial buildings don't use 2-wire dimming where you're messing with the sine wave on the hot wire for dimming, instead they give you a clean 120V circuit and tell you the dimming level over some other channel (whether it's wireless, 0-10V analog, or some digital bus), and these tend to perform a lot more consistently. But most residential equipment doesn't work that way because houses don't have the additional wiring for it, so we're stuck with 2-wire. When you get into 2-wire dimmers where it's chopping up the sine wave to reduce power, everything gets sloppier. The only 100% reliable strategy to avoid problems is buying LED bulbs that have been tested on your specific dimmer system. Consumer products are especially frustrating because a lot of time the technical specifications are missing important information like whether it's for forward phase or reverse phase dimming. That relates to which end of the sine wave gets chopped off for dimming, and they don't play nicely with each other. Reverse phase is the more common these days, but it doesn't hurt to confirm. Lutron does a fair bit of compatibility testing and lists their recommended products here: http://www.lutron.com/en-US/Service-Support/Pages/Technical/Design-SelectionTools/LEDDimmerMatrix.aspx http://www.lutron.com/en-US/Service-Support/Pages/Technical/... EDIT: I should note that if you're looking at screw-in LED light bulbs you want to search "A Lamp". Bit of industry jargon, we measure things in 1/8 inches (because reasons), so what normal people consider a standard lightbulb is an "A19 lamp" meaning A-series with 19/8" (2.375") diameter.

hammock 9y ago

And at the same time, lots of (anec?)data coming out that LEDs have adverse health effects

danmaz74 9y ago
Example?
- hammock 9y ago
  http://www.ledsmagazine.com/articles/2010/11/light-and-human-health-led-risks-highlighted.html http://www.ledsmagazine.com/articles/2010/11/light-and-human... http://www.cnn.com/2016/06/21/health/led-streetlights-ama/index.html http://www.cnn.com/2016/06/21/health/led-streetlights-ama/in...
  - Retric 9y ago
    That has little to do with LED's just a subset of cheap LED's.
    - wlesieutre 9y ago
      Pretty much all white LEDs are going to have high blue content. It goes back to how they work, these are actually phosphor converted blue LEDs where they pump out a ton of blue light and then use a phosphor layer to absorb and re-emit some of it at other wavelengths. See spectral distributions here: http://cdn2.goughlui.com/wp-content/uploads/2013/06/spectraldist.gif http://cdn2.goughlui.com/wp-content/uploads/2013/06/spectral... Even down at 2700K (blue line, "warm white") there's a substantial blue spike over on the left. The LEDs being used in most streetlights are cool white, probably 4000K+, definitely a lot of blue in that. There are high CRI LEDs available (Color Rendering Index - at warm colors it basically means "how similar do colors look under this vs under incandescent"), but they're much less efficient in terms of how much light you get per watt, and they tend to be a pretty niche product for lighting stuff where reds are important (brick walls, fruit, art, etc). Still some blue in that, but much less. https://www.yujiintl.com/img/graphics/warm-white-high-cri.png https://www.yujiintl.com/img/graphics/warm-white-high-cri.pn... As to health effects, from what I've heard the jury is still out, but there's a definite push toward "tunable white" in the industry. Whether anyone actually wants to pay for that when it comes time to choose between that or the cheaper fixed color temperature that we've been doing forever, things are less certain...
      - Retric 9y ago
        I don't disagree with what your saying, but... LED's don't produce light from heat so they don't really correspond color temperature. They can fake it, but the current approach produces blue at higher efficiency than yellow. Thus upping the yellow content results in lower brightness and lower 'efficiency' for the same device or identical brightness and higher costs. However, producing a lot of blue light is often sub optimal so you need a consumer willing to make that trade-off instead of just seeing white/cost/brightness and assuming that's the whole story. Thus, cheap really does mean more blue.
        wlesieutre 9y ago
        You're correct that LEDs aren't actually producing light like a hot black body radiator, but we still measure their shade of white using that scale as a reference. This is called the "correlated color temperature," which you'll almost always see abbreviated to CCT. It's not "this light was produced by a black body radiator at 5000K", it's "this light is perceived by the human eye as the same color as a 5000K black body radiator. Where does the human-perceived color fall on the Plankian locus? https://en.wikipedia.org/wiki/Planckian_locus https://en.wikipedia.org/wiki/Planckian_locus As far as cheapness, yes and no. The swimming pools that I've designed tend toward the more blueish whites and low CRI because they have a light level target to hit and that's the cheapest way to do it. With the exception of some small residential pools, they aren't trying to make a warm cozy feeling, they just want it to be bright enough to meet the requirements for safety / code / IES recommendations / NCAA requirements, etc. But a lot of lighting isn't done that way where you're determining the layout and quantity of lights to hit a target level at lowest cost. It's much more common that you pick the color temperature that you want it to look like and you buy that regardless of the exact light output. LED bulbs at the store have a Lighting Facts label that tells you the color temperature and how bright it is, and the different CCTs of a given brand bulb will cost the same. Yes, you get more light out of the more blue one, but when you're getting bulbs for you're house you'd never say "Get the 4000K version. It's an extra 100 lumens, so we can light the house with 17 of them instead 18 and save a few bucks." Interestingly there are cultural conventions to this too. In the US it's much more common to see the warmer color temperatures in homes and even in offices. In Asia and India you'll encounter a lot more blue.

criddell 9y ago

Maybe you can explain something for me. I installed an IOT dimmer to control my bathroom lights which are dimmable LED bulbs. It works, except for one super annoying thing: when I turn them on, it flashes first at full brightness before going to the correct setting. It's so bright, it almost feels like a camera flash. The dimmer is a Lutron Caseta dimmer and it works nicely with the Echo and Apple Home.

deleted 9y ago
[deleted]
akx 9y ago
I have LED lighting in my bathroom, controlled by a non-IOT but remote-controllable dimmer, and it does not exhibit that behavior, so I'd say it's just a buggy dimmer.
wlesieutre 9y ago
LED dimming is a compatibility mess. Most commercial buildings don't use 2-wire dimming where you're messing with the sine wave on the hot wire for dimming, instead they give you a clean 120V circuit and tell you the dimming level over some other channel (whether it's wireless, 0-10V analog, or some digital bus), and these tend to perform a lot more consistently. But most residential equipment doesn't work that way because houses don't have the additional wiring for it, so we're stuck with 2-wire. When you get into 2-wire dimmers where it's chopping up the sine wave to reduce power, everything gets sloppier. The only 100% reliable strategy to avoid problems is buying LED bulbs that have been tested on your specific dimmer system. Consumer products are especially frustrating because a lot of time the technical specifications are missing important information like whether it's for forward phase or reverse phase dimming. That relates to which end of the sine wave gets chopped off for dimming, and they don't play nicely with each other. Reverse phase is the more common these days, but it doesn't hurt to confirm. Lutron does a fair bit of compatibility testing and lists their recommended products here: http://www.lutron.com/en-US/Service-Support/Pages/Technical/Design-SelectionTools/LEDDimmerMatrix.aspx http://www.lutron.com/en-US/Service-Support/Pages/Technical/... EDIT: I should note that if you're looking at screw-in LED light bulbs you want to search "A Lamp". Bit of industry jargon, we measure things in 1/8 inches (because reasons), so what normal people consider a standard lightbulb is an "A19 lamp" meaning A-series with 19/8" (2.375") diameter.