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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

#261

Post by throw0101a »

Angostura wrote: post #242
herf wrote: post #134

(Michael from f.lux): this kind of thing is necessary for most buildings, because otherwise people don't get a "day" signal when they spend time indoors. Most of us spend >90% of our time inside. However, we shouldn't mess with light levels like these (or even somewhat lower ones) without some limits, and the main one is some automatic timing to turn things down after it gets too late. Otherwise you will find yoursel…

Is there any solid peer-reviewed, published papers on this stuff? While it sounds intuitively correct and attractive, I've struggled to find anything rigorous that shows light colour and intensity in the evening has an effect of sleep quality - its all anecdotal.

The general field of study is called chronobiology. Doing a search for "chronobiology light sleep" gives all sorts of results. One example:

> Environmental light synchronizes the primary mammalian biological clock in the suprachiasmatic nuclei, as well as many peripheral clocks in tissues and cells, to the solar 24-hour day. Light is the strongest synchronizing agent (zeitgeber) for the circadian system, and therefore keeps most biological and psychological rhythms internally synchronized, which is important for optimum function. Circadian sleep-wake disruptions and chronic circadian misalignment, as often observed in psychiatric and neurodegenerative illness, can be treated with light therapy. The beneficial effect on circadian synchronization, sleep quality, mood, and cognitive performance depends on timing, intensity, and spectral composition of light exposure. Tailoring and optimizing indoor lighting conditions may be an approach to improve wellbeing, alertness, and cognitive performance and, in the long term, producing health benefits.

* https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3553574/

There are 61 foot notes in the above paper, so that should help you get starting going down this rabbit hole. :)

Re: Rooms can be as bright as the outdoors

#262

Post by mrb »

ars wrote: post #174
mrb wrote: post #157

Earlier quoted context omitted.

Same experience here. I film all the led bulbs I purchase in 240fps to see if they flicker at 60Hz. I discovered that Philips bulbs NEVER flicker. Occasionally I stumble upon other cheaper brands that don't flicker, but there is never any guarantee. I might buy 2 batches 6 months apart of bulbs from the same model from the same third party seller on Amazon, and they slightly changed the product (updated packaging and…

A ton of LEDs flicker at 120hz which makes me crazy. It's like a strobe effect that I only see when moving.

Oops I wrote 60Hz but meant 120Hz.

Re: Rooms can be as bright as the outdoors

#263

Post by taneq »

dijit wrote: post #210
SirHound wrote: post #124

Earlier quoted context omitted.

No this isn’t typical. Are you particulary good at coping with jetlag?

I identify with the parent, and I've always been fine with "jet lag" to the point where I often don't even notice it or it only lasts until I go to bed the first night. (IE; Sweden->Los Angeles, the inverse is harder but not as hard as most people seem to have it, it knocks some colleagues out for an entire week)

A week? Yeah I'm scragged for a day if I'm losing hours on a flight (although this is exacerbated by the fact that if I'm flying east I'm usually going from my 'starts around 9ish' desk job to 'be on site by 6am' minesite commissioning, so I'm effectively waking up at 2am when I'm used to waking up at 8:30am) but after that I'm fine.

Re: Rooms can be as bright as the outdoors

#266

Post by dghughes »

nnq wrote: post #259
dghughes wrote: post #254

Earlier quoted context omitted.

> ...that HELPS us ADD-iacs focus waaaay better That's interesting since I too can only really focus at night or late evening. I knew someone with ADHD and I could see some glimpses of me in their behaviour.

Not sure if it generalizes. And if it does, not sure if it does do all ADDs: I'm ADHD without the Hyperactive component, subclinical, ADD or (ADHD-PI or Inattentive-ADHD more precisely). Or with the H component purely mental/internal, which kind of sucks because you get the "benefits" of ADHD plus a higher propensity to slide into an unhealthy ultra-sedentary lifestyle.

That too seems familiar. I'm not sure if I am hyper or not I used to be but I think I outgrew it finally but it took decades.

The ultra-sedentary lifestyle seems very accurate. I make a plan for example study for my CCNA and here I am six month later finally doing it. This is with daily reminders to myself, set alarms, notes, collecting study material etc. not just thinking but some prep.

And when I am in the zone I tend to overdo it often way too much detail. Brevity is not my forté.

Self medicating with caffeine seemed to be working it would help me focus even during the day. But I think it contributed to my fatty liver I never had it before or after my energy drink addiction. Now it's one cup of coffee per day max.

Re: Rooms can be as bright as the outdoors

#267

Post by akvadrako »

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…

You might want to try a 28-hour day.

Re: Rooms can be as bright as the outdoors

#268

Post by graeme »

I'm in Canada, so the bulb he selected isn't readily available. Anyone found a good one with high CRI?

Also, it's not clear to me how important the watts/lumens are in a single bulb vs. multiple. If I can only find 100W/6000 lumen bulbs, are three of those the same as one higher wattage bulb with 18000 lumens?

Re: Rooms can be as bright as the outdoors

#269

Post by bildung »

lm28469 wrote: post #235
bildung wrote: post #230

Earlier quoted context omitted.

> Type "blue light circadian rhythm study" on google and you basically only find studies supporting that blue light has a negative impact. But the moment you actually evaluate the studies, you'll find that almost all * don't research blue light specifically, but light at all * use unrealistic settings, like 4 to 8 hours bedtime reading (really) * don't properly control for other known sleep affecting factors - and ha…

> Full sunlight has up to 30000lux of blue light alone Well yeah that's the whole point, blue light during the day is perfectly fine, that's how your body knows it's time to get shit done, sitting in front a screen after sunset during X hours _will_ fuck up your rhythm and blocking blue light will moderately mitigate the issue. > else people in scandinavia would have severe problems with their circadian rhythms. They…

Even on a cloudy winter day the sun's luminocity is about 20 times higher than a very bright phone display.

My point is that it is not reasonable to assume a strong physical reaction if the artifical light is so much weaker.

Note I'm not denying that there isn't a small effect! But it is probably dwarved in comparison to a change in eating habits, anti stress methods like meditation, sports and so on.

> It's 100% a fact that blue light is the light which impact the production of melatonin the most, and that melatonin directly regulate your circadian rhythm.

Then why don't most studies study effects on the actual circadian rhythm? My guess is because the results there are less clear with actual sleep (i.e. they actually studied both but only published the "good" results - a sad side effect of publication bias).

BTW the same is true for light therapy for prevention of winter depression: There probably is an effect, but it is so weak that rigorous meta analysises don't show real evidence.

My overall point is: There seldom are strong effects with most treatments of this kind. If there were, we already would have found out in pre science times. People are doing artifical lighting for thousands of years (think campfires, not LED lights).

Re: Rooms can be as bright as the outdoors

#270

Post by DenisM »

tzs wrote: post #159
DenisM wrote: post #105

Anyone knows a decent and inexpensive way to measure CRI? It seems like a simple enough problem with a prism and a monochrome CCD sensor, yet the cheapest device I can find is over a thousand dollars.

I wonder if it would be possible to write an app that could do it using the camera in a smart phone? The idea is that you would take some photos of some reference objects of known color under sunlight, and then take photos of those same objects under the lighting you are testing, and then figure out from the differences in the photos what the CRI must be. The reference objects could be well known, easy to obtain hous…

I'm afraid that phone camera sensors are filtered to R/G/B, so a strong monochromatic orange, for example, may end up under-represented or even absent in the captured image, and will likely be hard to distinguish from an overlap between red and green.

Maybe modern image processing techniques can figure it out, but this seems like a huge problem to me.

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