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Comment by awakeasleep | Hacker News Reader

However, if you want good full spectrum LEDs (that approach what an incandescent bulb provides) I believe you must buy really expensive ones that are only manufactured in Japan https://www.yujiintl.com/high-cri-led-lighting

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You may be viewing the past with a rose filter. Incandescent light bulbs are nowhere near full spectrum. You have a decent analysis of the emitted frequencies here:

https://www.comsol.com/blogs/calculating-the-emission-spectr...

I assumed that full was always a relative term. You surely don't want devices that emit on the whole EM spectrum.

> You have a decent analysis of the emitted frequencies here:

That still shows something approaching a black body radiatior. The difference is just the planckian locus. In other words it does emit a full spectrum, just with a power distribution that mimics sunset light and not midday sunlight.

I remember the transition, and “A/B testing” different rooms in my parents house as our last incandescents died, quite vividly. It was awful. It still is, but people no longer have good quality light for comparison.

And you no longer have a room lit with incandescent to compare with the current, much improved offerings :)

They maybe be expensive but will last a decade or longer, so price is negated. And when you replace in 10 years, price will be minuscule as to what it is now.

For daytime hours I would like something approximating the suns spectral output. Something like a black body at around 5800K. Lots of blue but pretty flat in the visual spectrum.

For the evening I would prefer more of a wood fire or candle light spectrum. That seems to help with people's sleep cycle. Something with a black body temp of about 1500 K. Or cool incandescent if you are reading; around 2400K. Majority red spectrum.

It already exists.

https://www.usa.philips.com/c-m-li/warm-glow-dimmable-led-li...

It's weird that their website gives no indication that they function this way. They don't say anything about blue light or sleeping better.

Phillips and some other known brands sell a wide spectrum of different LED bulbs these days. Some are way better than others. I am sure someone is making the 'best' but the better average is not as bad anymore IMO.

You're not understating things when you say "really expensive"...

https://store.yujiintl.com/collections/high-cri-led-lights

Wow.

I can confirm the quality of the devices they send. And from the shipping it seems to be Shenzen. Their 1900K VTC (triple-phosphor) LEDs seem to be out of stock though. They have 80+CRI on candlelight. DIY Perks (youtube) got some and made a video destribing the difference between their double phosphor and 'normal' chinese LEDs. One can see the quality of the actual LEDs (not the packaging/phosphor(s)) by running them at threshold voltage, and seeing if all dies in the package light up simultaneously. If they don't, the device is of 'chinesium' quality. Ask for a refund, as it's going to burn out soon (uneven current distribution between the parallel columns).

And as far as "really expensive" goes: the price of the LED is 10% of the electricity cost over a life of 50k hours, which is about what you get out of them without fancy cooling. See http://www.wolframalpha.com/input/?i=Plot%5B(1000.+%2B+0.2+x... , for TCO over time. Units are EUR and hours, and I calculated a price of 20ct/kWh. You can take these prices as net prices for USD, tax and forex cancel out. Yes, these are not economical if you don't use them. In that case, use cheap filament bulbs or similar. Don't cheap out on the quality of light you use. Get double phosphor (other manufacturers offer those too) for normal use, and consider triple phosphor for uses where color rendition is particularly important (photo shooting/inspecting things/etc). For the mentioned price you can get a cheap driver and the LED, but please don't burn your LED with inadequate cooling or a bad driver. They are not cheap ;)

Do you use these for home lighting, and if so, how do they compare to traditional CFLs? Or would that be total overkill?

106$ for a pack of 6 led light with CRI > 95 doesn’t seem really expensive to me... It’s less than 18$ each.

Well, it seems really expensive when I compare to the price of led lights I'm used to. eg local supermarket. :)

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