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Rooms can be as bright as the outdoors

benkuhn.net

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Re: Rooms can be as bright as the outdoors

#301

Post by Al-Khwarizmi »

avar wrote: post #279
Al-Khwarizmi wrote: post #213

Earlier quoted context omitted.

In Spain we have lots of problems and room for improvement in many issues, but one thing I can be proud of is that the vast majority of homes have blinds that close completely and get zero light in. I often wonder why it isn't like this elsewhere, and especially in northern places where it would be especially convenient (I get that it's possible to adapt, but wouldn't it be nicer to be able to sleep in any position?)…

I'm assuming you're talking about the exterior metal curtains common to Spanish houses (persiana con cajor exterior [1]). Those are only incidentally to block out light, they're mainly for thermal management. You put them down in the middle of the day to keep hot air and direct sunlight out. A system like that is completely unsuitable in places that get snow. If you installed it on a house in Iceland it would at best…

As far as I know, they are for both purposes. In fact, most of them can be lowered enough to provide thermal insulation but still let light through (they have small horizontal holes for that purpose), but if they are lowered more, the holes close and they block light. So it's definitely a planned feature, not a side effect.

In most of Spain they are installed outside of the window glass, but in the north they are installed inside, so they are protected from cold and wind. As in this picture, for example (just found at random): https://www.inmoatuel.com/piso-exterior-de-90m2-reformado-a-...

But they still seal the window hole perfectly so they block light much better than blackout curtains. I suppose the problem with Monachil is that it's a cold place, but within Andalucía which is generally warm, so they don't have a tradition in the area of installing blinds inside as is the case, for example, in Galicia, where you can definitely see them even at high altitudes where snow is common.

When I go on a camping trip... indeed I just don't sleep well, I'm afraid :)

Re: Rooms can be as bright as the outdoors

#302

Post by jasonmp85 »

kragen wrote: post #106
exikyut wrote: post #89

Earlier quoted context omitted.

What about transreflective displays? Annoyingly I've still not seen one IRL. They go black and white, apparently, but are still 100% legible.

I've been positively impressed with the readability of OLPC XOs in sunlight, which I think are what you're talking about. It's too bad they weren't willing to consider a capitalist rather than communist model for making them available; I think they would have been popular. I think there are also color transflective displays but I've only seen them in photos. E-ink displays are even better than the XO, and machines wi…

Oh my god this is the most insane description of OLPC I’ve ever seen.

Not “neoliberal private-public partnership bull crap” but somehow “communist”? Lololol.

Re: Rooms can be as bright as the outdoors

#303

Post by kragen »

jasonmp85 wrote: post #302
kragen wrote: post #106

Earlier quoted context omitted.

I've been positively impressed with the readability of OLPC XOs in sunlight, which I think are what you're talking about. It's too bad they weren't willing to consider a capitalist rather than communist model for making them available; I think they would have been popular. I think there are also color transflective displays but I've only seen them in photos. E-ink displays are even better than the XO, and machines wi…

Oh my god this is the most insane description of OLPC I’ve ever seen. Not “neoliberal private-public partnership bull crap” but somehow “communist”? Lololol.

The only way they would sell you an XO was if you were going to give one to every kid in the country as part of a centrally planned education policy. While this could have been very effective, there's no denying that it's structurally much more Lenin or Castro than Pinochet, Eisenhower, or even Yew. If that's not obvious to you, it says more about your knowledge of political ideas than about my mental health; perhaps you only know “communist” as a pejorative due to US jingoism?

A capitalist approach to the problem would have stopped them from failing as completely as they did but also would have eliminated the possibility of the far-reaching transformation of education they were seeking to impose.

Re: Rooms can be as bright as the outdoors

#304

Post by jiofih »

bildung wrote: post #300
jiofih wrote: post #274

Earlier quoted context omitted.

Campfires are not artificial light. This is about blue light after all. You need to show some data to back your statements besides hand-waving all existing studies in one swoop.

Campfires are artifical as in they are not the sun, and people were exposed to their radiation for millenia. A fire obviously emits most of its electromagnetic radiation in the IR band, but it the emission goes down right into UV. This is not exactly rocket science, just point a UV/Vis spectrometer at a fire and see for yourself. I'm not quite sure why you think I should provide data - I'm not the person postulating…

You are indeed making claims, and worse, generalizing a “lack of evidence” from a handful of unrelated studies you picked. It’s kinda obvious that not all of the studies linked in the flux page are about blue light specifically, but how electronic device usage affects health. The effect of blue light is widely accepted in the scientific community and not some kind of fringe theory.

On your campfire rant, first, luminosity is an astronomy measure, what matters for humans is the perceived light (lumens); nobody stares at a campfire directly and the little light bounced from the surroundings has very little blue; on the other hand, you literally stare non-stop for hours at the blue light from your phone, which makes the amount it emits a lot more relevant.

Re: Rooms can be as bright as the outdoors

#305

Post by bildung »

jiofih wrote: post #304
bildung wrote: post #300

Earlier quoted context omitted.

Campfires are artifical as in they are not the sun, and people were exposed to their radiation for millenia. A fire obviously emits most of its electromagnetic radiation in the IR band, but it the emission goes down right into UV. This is not exactly rocket science, just point a UV/Vis spectrometer at a fire and see for yourself. I'm not quite sure why you think I should provide data - I'm not the person postulating…

You are indeed making claims, and worse, generalizing a “lack of evidence” from a handful of unrelated studies you picked. It’s kinda obvious that not all of the studies linked in the flux page are about blue light specifically, but how electronic device usage affects health. The effect of blue light is widely accepted in the scientific community and not some kind of fringe theory. On your campfire rant, first, lumin…

Well then, feel free to provide the research. You can then also send it directly to UK's General Optical Council because they actually sue companies who claim health benefits from blue light filtering [1] because there is no evidence for real-world effects. Or the EU's Scientific Committee on Health, Environmental and Emerging Risk, because they, too, say that there is no scientific base for the claim of real-world effects [2, page 90]. Or Cochrane review, who say that there is no health effect in case of macula degeneration [3].

Also please don't get personal. My campfire illustration was not a rant, it was an illustration of humans using light after sunset. It is a fact that they did so for millenia. It is also a fact that a 1300K hot fire emits blue light and even UV light.

And luminosity (lux) is just luminous flux (lumens) per square meter. Astronomers use that because luminosity is the measure used to compare different light sources. If comparing e.g. a ceiling light and a phone screen one uses luminosity because that makes both light sources easier to compare. It is also the measure most research on light effects work with. You could of course multiply the 1000lux of a bright phone display with its surface area in square meters if you prefer to calculate in lumens.

[1] https://www.aop.org.uk/ot/industry/high-street/2017/05/26/bo...

[2] https://ec.europa.eu/health/sites/health/files/scientific_co...

[3] https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD...?

Re: Rooms can be as bright as the outdoors

#306

Post by massaman_yams »

bryanmgreen wrote: post #272
rajbot wrote: post #155

Earlier quoted context omitted.

Have you considered manufacturing f.lux for home lighting, such as a wall-mounted controller for Hue or Ikea bulbs that changes color spectrum depending on time of day? Or possibly bulbs with f.lux build in, so no external controller is required?

YES YES YES. I've been looking for a hardware solution to this problem so long. I would kill to have like a programmable dimmer knob that can progressively adjust both temperature and power set to a fixed temperature and power at start (ie: 3750k at 100%) and finish (ie: 2500k at 10%) positions then it auto-calculates the right spot in-between. Does anyone know if I could do this on a Pi?

I did it with a Pi, HomeAssistant, smart bulbs, and some Python, but it was not as good or as reliable as I'd like.

I wanted the lights to know what temperature and brightness to turn on to based on a schedule, but there wasn't a way for them to pull the desired state upon power-on; instead I'd have to detect power on and push a state change to the desired color temp. This meant they'd turn on at whatever last state they had on power-off, and a few seconds later (or frequently much slower) adjust to scheduled color temp.

This may have worked better had I used smart switches to turn lights on/off rather than wall switches that cut power to the bulbs, but I also had issues with the smart hub losing connection to bulbs occasionally, HA not reliably seeing power-on events for the bulbs, and HA losing connection to the hub. (Bulbs/hub were Ikea tradfri; perhaps other manufacturers' products are more reliable).

This was a couple years ago; I haven't looked into it much since - maybe it would be easier to do now.

Re: Rooms can be as bright as the outdoors

#307

Post by jessaustin »

ars wrote: post #172
anewguy9000 wrote: post #114

Earlier quoted context omitted.

yup. like my low flow toilet that i need to flush twice...

Not anymore, technology has improved a lot! Get this one (or variant on it): https://smile.amazon.com/gp/product/B001KAFKRM I've owned it for 5 years and it's clogged only once (it happened in the first week of ownership) then never again. And one time (in 5 years) I needed to flush it twice.

That one is bragging about a 3" valve. There are other toilets available now that have 4" valves.

Re: Rooms can be as bright as the outdoors

#308

Post by avar »

Al-Khwarizmi wrote: post #301
avar wrote: post #279

Earlier quoted context omitted.

I'm assuming you're talking about the exterior metal curtains common to Spanish houses (persiana con cajor exterior [1]). Those are only incidentally to block out light, they're mainly for thermal management. You put them down in the middle of the day to keep hot air and direct sunlight out. A system like that is completely unsuitable in places that get snow. If you installed it on a house in Iceland it would at best…

As far as I know, they are for both purposes. In fact, most of them can be lowered enough to provide thermal insulation but still let light through (they have small horizontal holes for that purpose), but if they are lowered more, the holes close and they block light. So it's definitely a planned feature, not a side effect. In most of Spain they are installed outside of the window glass, but in the north they are ins…

The picture you linked to is taken in A Coruña whose mean temperature is around 10 degrees higher[1] still than relatively mild[2] climates near the arctic circle.

I didn't mean to suggest they weren't also used to let light in. I've spent a lot of time in houses that have these installed, letting light throughout the day while keeping the house relatively cool is a constant balancing act. I meant that without the need for the thermal management you'd go for other sorts of systems, such as internal blinds.

I.e. I'd expect that in places like A Coruña you'd use these for thermal management in the summer with the outer windows open, whereas in Iceland there's maybe 1-3 days of the year where the outside temperature is anywhere near the inside temperature.

1. https://en.wikipedia.org/wiki/A_Coru%C3%B1a#Climate

2. https://en.wikipedia.org/wiki/Akureyri#Climate

Re: Rooms can be as bright as the outdoors

#309

Post by Tepix »

BenoitEssiambre wrote: post #42

The corn cob bulbs are very hard on the eyes unless you have some kind of diffuser. I found a better solution is a 1 to 7 bulb splitter with 7 150W equivalent bulbs for a total of about 15000 lumens. https://www.amazon.com/8T8-Splitter-Standard-Converter-Comme... I'd be curious trying a spotlight (something like this: https://www.amazon.com/Primelux-8-inch-14400-Lumens-Driving/... ) that is farther away from me. The…

I was thinking about getting this myself, too. I looked at dozens of corn cob light bulbs on eBay and AliExpress and found none with a CRI of 90 Ra or better. In Germany you can buy cheap 13W E27 LED light bulbs at Aldi every January with 95+Ra.

Re: Rooms can be as bright as the outdoors

#310

Post by nicoburns »

helpPeople wrote: post #285
nicoburns wrote: post #271

Earlier quoted context omitted.

The fact that bulbs are 1. small and 2. run on mains electricity is a big complicating factor. By far the easiest way to build this would be with dual-colour LED strips. But that's not how most people want to light their homes.

Electrical engineer here. What is hard about these? For a few dollars I can convert 120v to whatever I want. Sell a different version to Europe

As a software developer, the fact that I even have to build custom electrical hardware is a significant barrier.

The fact that this hardware runs at 120v (or 240v in my case) makes it the barrier higher as there's now a chance that making mistakes might kill me.

Additionally, the high power levels mean that adequate cooling is needed, and as a non-expert it's hard for me to know whether I've done that correctly.

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