Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Rooms can be as bright as the outdoors

benkuhn.net

Post reply on HN
Print view View original

91–100 of 317 posts

Re: Rooms can be as bright as the outdoors

#91

Post by ComputerGuru »

rococode wrote: post #38
ComputerGuru wrote: post #29

Earlier quoted context omitted.

CRI is the real key. A lot of manufacturers have cut back on quality in the war over pricing. Philips had the very best consumer LEDs then started pushing their “SlimStyle” garbage with a CRI of barely 75. Amazon is littered with products advertising CRI “over 90” but in reality are probably barely breaking 80.

What's the effect of different CRI on humans? I'm curious what the difference is between good and bad CRI, and if a person would be able to notice it.

I don’t know about physiologically but perceptually it feels dimmer and drearier. The room feels gloomy although there is certainly sufficient “quantity” of light. It’s almost like everything takes a few milliseconds longer to resolve.

That, of course, is apart from the actual being unable to see certain shades of color and the spectrum being skewed one way or the other.

Re: Rooms can be as bright as the outdoors

#92

Post by Marsymars »

ComputerGuru wrote: post #29
spectramax wrote: post #22

Earlier quoted context omitted.

Have you checked the CRI? Its not bad but not great either - 84 as per the specs. There are a lot of Chinese cheap LED fixtures available on Amazon and no one seems to care about the CRI - it defines how colors appear in your room.

CRI is the real key. A lot of manufacturers have cut back on quality in the war over pricing. Philips had the very best consumer LEDs then started pushing their “SlimStyle” garbage with a CRI of barely 75. Amazon is littered with products advertising CRI “over 90” but in reality are probably barely breaking 80.

CRI is useful, but it's not a perfect measurement. You can make an 80 CRI bulb that subjectively looks pretty good for many use cases, or a 90+ CRI bulb that looks bad. (e.g. with poor R9 measurements.)

Re: Rooms can be as bright as the outdoors

#93

Post by Marsymars »

benkuhn wrote: post #55
Scoundreller wrote: post #3

> Isn’t this expensive to run? It draws about 2 kWh per day (assuming 8h of usage), which costs about $0.30 at typical rates. This is comparable to one day of a modern fridge or one load of laundry. Power is cheap, folks! But it will offset your other heat sources. If you live alone, you can treat it like a room heater and lower the temperature for the rest of your home. Since the bulb is radiating heat some degree o…

While LEDs do produce some waste heat, efficient ones convert 50%+ of the input power to visible light, so it's less than you might think (compare to ~10% for incandescents, iirc). The bulb I have doesn't have a perceptible effect on my room temperature (although I guess it probably does cause the thermostat to turn on a tiny bit less often).

That visible light is still mostly ending up as heat in your home though, other than what spills out of windows.

Re: Rooms can be as bright as the outdoors

#94

Post by jacquesm »

wheels wrote: post #51

I usually eschew labels, preferring simply "sleep weirdo", but I fit the pattern of "Non-24 Sleep-Wake Disorder", with my sleep and waking times drifting progressively later at semi-regular intervals. The result is that I'm often awake through the night. (This week I'm going to bed around 9:00 a.m.) Even with that, I've noticed some pretty big productivity swings based on the season. Interestingly, this hit me very h…

Good morning to you Scott, Much the same here, I never could keep a rhythm.

Re: Rooms can be as bright as the outdoors

#95

Post by [deleted] »

abakker wrote: post #16

I’ve got 5 of these in my office. https://www.superbrightleds.com/moreinfo/industrial-led-ligh... . They are fantastic. I have several more of the longer fluorescent replacements in my wood shop. More light is magnificently better for energy and productivity in pretty much all environments. I would still prefer skylights to bulbs, but these are a good solution for dark rooms.

[deleted]

Re: Rooms can be as bright as the outdoors

#96

Post by natmaka »

te0006 wrote: post #21
GuiA wrote: post #4

Every few years some company/research lab will claim they have a technology that’ll simulate sunlight coming through a window, but it still isn’t something one can buy. The moment we can buy eg a 3ft by 1ft panel that we can just mount on a wall and feels like an actual sunlit window for a few thousands dollars or so, interior design is likely going to get radically different. (And that’s not to mention the sci-fi dr…

Have a look at https://www.coelux.com/ . (Not affiliated, I just like the concept. But AFAIK their 'panels' still are 50+ cm thick and outside your as well as my price range.)

See also https://en.wikipedia.org/wiki/Light_tube

Re: Rooms can be as bright as the outdoors

#97

Post by marcosdumay »

wheels wrote: post #78
gligorot wrote: post #68

Earlier quoted context omitted.

I absolutely hate LEDs. I don't know why, but I just hate them. Especially the white ones. The yellower are similar to a mid summer day and I can cope with them, but there's always this feeling of something being off. I guess it's connected to us humans being used to non-sun light being (similar to) a fire - mainly consisting of yellow/orange tones. Also, I don't exactly remember from where I read this, but when a (t…

> I absolutely hate LEDs. I don't know why, but... I'm really interested in the why . Most people don't seem to care. My in-laws have CFLs in their living room that just feel horrible to me, but they're none the wiser. I'm very curious as to what it is in the light spectrum that seems to matter to some (small) class of people, myself, and it sounds like you, included. The word for "fire-like" light, used in my origin…

Well, fire does not shine by black-body radiation. Lamps try to emulate a black-body because that's what color standards dictate and labs test against, but fire has a very bad color resolution. (By the way, daylight isn't also like black-body radiation, but it's much closer than fire.)

Personally, flickering makes me ill. I am used enough to 120Hz to survive it, but any other frequency is bad. Also, the 6400K LEDs look way too blue, much bluer than the Sun. That may be because I have a relatively rare kind of color blindness.

Re: Rooms can be as bright as the outdoors

#98

Post by jrockway »

Mountain_Skies wrote: post #67
jrockway wrote: post #41

Earlier quoted context omitted.

I bought some LEDs on Amazon and uploaded charts showing the wavelength distribution. The LEDs were awful and the charts made it very clear why. Amazon deleted my review and the item currently has 5 stars. The best lights I have are some warm white LED strips from eBay. I glued them to the top of my workbench (it's a desk under some shelves basically) and it is a joy to work there. I measured them and they are pretty…

Did the CRI for the LEDs you bought match that which was listed or did they even have a CRI stated? I'm willing to spend extra for high CRI but so much junk on Amazon outright lies about being UL listed, it wouldn't surprise me if they started lying about CRI once they realize it is a selling point.

Yeah, they claimed a CRI of 91 but it was closer to 70, I think. (Measured with ArgyllCMS and a Colormunki Photo.)

You could tell it was wrong just by looking. It wasn't a measurement that only appeared by looking at it with expensive equipment; you turned the lights on and instantly though "this is completely unusable". I only measured it to see how bad it was.

Re: Rooms can be as bright as the outdoors

#99

Post by aasasd »

derefr wrote: post #65

> Other than “we’ve been doing it for a while,” there seems to be no reason to expect that being in a 100x dimmer environment all day wouldn’t be awful. Indoor darkness seems to be one of those things that we don’t question only because it’s been that way forever. An interesting question is: what average light levels existed in the Environment of Evolutionary Adaptedness for humans, given the types of things our ance…

I've been wondering the same about ‘normal’ levels of activity. Pretty sure most of us are horribly motion-deprived by the standards of hunters or gatherers. But then again, presumably someone also was staying behind at home, and I don't remember any folk wisdom saying housekeepers are all dystrophic.

Re: Rooms can be as bright as the outdoors

#100

Post by klyrs »

marcosdumay wrote: post #97
wheels wrote: post #78

Earlier quoted context omitted.

> I absolutely hate LEDs. I don't know why, but... I'm really interested in the why . Most people don't seem to care. My in-laws have CFLs in their living room that just feel horrible to me, but they're none the wiser. I'm very curious as to what it is in the light spectrum that seems to matter to some (small) class of people, myself, and it sounds like you, included. The word for "fire-like" light, used in my origin…

Well, fire does not shine by black-body radiation. Lamps try to emulate a black-body because that's what color standards dictate and labs test against, but fire has a very bad color resolution. (By the way, daylight isn't also like black-body radiation, but it's much closer than fire.) Personally, flickering makes me ill. I am used enough to 120Hz to survive it, but any other frequency is bad. Also, the 6400K LEDs lo…

> Well, fire does not shine by black-body radiation

Flame, not entirely; embers, yes.

Post reply on HN