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| Biden admin moving forward with light bulb bans in coming weeks |
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| james_s:
--- Quote from: coppice on April 03, 2023, 06:08:28 pm ---Huh? Incandescent lamps flicker. Its 100Hz/120Hz and doesn't go anywhere near zero, but its there. A decent LED has a really steady output. --- End quote --- Come on, don't feign confusion, you know what I'm talking about, a few years ago after a similar debate came up and people insisting that the bulbs didn't flicker I connected a photodiode to a scope and demonstrated it. Out of a random selection of LED bulbs I grabbed, most of them flickered, some sharply, some at mains frequency, some at the driver frequency, some both. The flicker form an incandescent lamp is negligible, just a little 120Hz noise on the top of a smooth line, the thermal inertia of the filament provides a great deal of filtering. Next to one of the flickery LED bulbs (the filament type with no space for a proper driver are typically the worst) the difference is like night and day. Maybe I should have used the word "strobe" instead of flicker. Many LED lights strobe, some do not but many do, incandescent bulbs do not, even the cheap ones. For this reason I always buy a sample of a particular bulb so I can evaluate it for my needs before I buy more of them. As I've said many times, I have long been a big fan of LED bulbs, but I don't pretend that they are flawless, the light quality can be good, but it's not better, they simply do not have a full spectrum and even the best cannot achieve a CRI of 100, this is a fact. |
| james_s:
--- Quote from: Zero999 on April 03, 2023, 08:46:42 pm ---I suppose the question is: there may be advantages of incandescent for some, but are they really worth the extra running cost? Is the law really necessary? If only a tiny minority of people use incandescent, then it's not going to make much difference in the grand scheme of things. An alternative to banning, would simply tax them so they cost the same as LED. --- End quote --- For me, no, the energy savings outweighs the handful of disadvantages, but that's a personal decision that I have no right to make for others. I have advocated since the very start a tax on less efficient lamps to subsidize more efficient types. I have a fundamental ethical problem with bans and very little tolerance for authoritarian types. I don't like being pushed around and and don't tolerate it, nor do most people, even the ones that support banning and mandating things get upset when somebody tries to force something on them. I will dig in my heals and push back in response when somebody tries if only because I absolutely refuse to validate bullying. |
| Gyro:
--- Quote from: james_s on April 03, 2023, 08:42:41 pm ---Good for you, I also have been happily using LED lighting in my home for as long as it was available, as I mentioned I was an early adopter. It's good, but the light is not as good as incandescent, it's close, and the energy savings and long lifespan are enough to make me choose it, but the lower CRI and lack of continuous spectrum, which are objectively true and easily measured traits makes colors look less vibrant, this is particularly true of reds and browns. If you don't notice or care that's fine, a lot of people don't, but that doesn't mean it isn't a valid issue. 5500k is nice for my laundry room and garage but for a cozy living space it sounds horrid, to each their own. ... --- End quote --- The first time I held a spectroscope up to a bog standard diy store LED lamp, I was struck by how continuous the spectrum actually is. None of the spectral peaks that you get with a florescent. The phosphors are actually pretty good these days. Obviously as you go towards the cold end of the spectrum colour temperature range, you'll get more of the LED blue fundamental showing through. |
| james_s:
--- Quote from: Gyro on April 03, 2023, 09:00:31 pm ---The first time I held a spectroscope up to a bog standard diy store LED lamp, I was struck by how continuous the spectrum actually is. None of the spectral peaks that you get with a florescent. The phosphors are actually pretty good these days. Obviously as you go towards the cold end of the spectrum colour temperature range, you'll get more of the LED blue fundamental showing through. --- End quote --- LED is far superior to fluorescent in that respect, that's certainly true. Attached are spectral plots of an ordinary incandescent lamp, a Philips remote phosphor LED which is the first really good LED lamp I encountered and the type I bought a bunch of back around 2011, and finally a 2700k trichromatic compact fluorescent. The trichromatic lamps were revolutionary in terms of efficiency and light quality compared to older types but still pretty bad compared to sunlight and incandescent. Where most fluorescent and LED sources fall short is in the red end of the spectrum. The trichromatic red is closer to red-orange than to a true blood-red, and most LEDs are deficient in the red end of the spectrum too. Many high CRI LED lamps include some true red emitters to boost this, but it comes with an efficiency penalty because the eye is less sensitive to red. It's this lack of true deep red that makes red and brown objects look a bit off. |
| Gyro:
Well obviously, by definition, you're not going to match the sunlight or tungsten filament (although it's impossible to run one hot enough to bring up the blue end to an acceptable level), but there are none of the obvious 'holes' that you might expect. |
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