
Rooms can be as bright as the outdoors - luu
https://www.benkuhn.net/lux
======
herf
(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 yourself
staying at work later and later each day, and it's no accident.

Our clocks don't work that well with more than about a 14-15 hour photoperiod
("day"), so spending 18 hours under 5000 lux will screw up your overall
rhythms, making your internal day longer than 24 hours and reducing your
sleep. This is considerably worse if you're a natural night owl - it will make
you later, faster.

The myth of electric lighting is that we can live in a permanent summer and
turn the wintertime into summer, but there are important seasonal questions
that we should think about too. For instance, cancer progresses much faster in
summer than in winter [edit: cancer progresses much faster in constant light:
winter vs. summer is complicated], and the winter schedule even engages a
different part of the central clock in your brain than the summer schedule
does. There are some important things going on here, which we've mostly tried
to remove from our environments.

Knowing how the body works and having the capability to change it really do
need to evolve in parallel - I think there is way more capability than
knowledge right now.

~~~
rajbot
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?

~~~
herf
Yes, we were looking at this quite a while ago. Lighting is a _really_ hard
business (especially residential) so we did not make the leap, and mainly have
tried so far to work with people who are in that business.

We thought back then that some form of "smart lighting" would be universal.
This mostly hasn't happened, so the truth is that the opportunity is different
than we had guessed. Today most "smart" replacement lamps are $20+, similar to
several years ago, even though normal lamps are $1.

We do support a lot of integrations with f.lux on Windows, so people can use
f.lux with their Hue/LIFX/yeelight/etc., but it is somewhere <2% of our users
right now.

~~~
posedge
Out of curiosity, what makes lighting such a hard business?

I have given the issue some thought as well. f.lux integration with Hue is
great, but unfortunately not a solution for me, as I'd have to keep my windows
pc running all day.

~~~
nicoburns
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.

~~~
helpPeople
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

~~~
Itsdijital
I think it's the cost. You can make a cheap driver off 120V that looks like
shit and has terrible thermals.

A solid driver with good filtering and good thermal characteristics is
expensive. So you're left with a $15 LED bulb that sits on a shelf next to $5
bulbs, selling to customers who see nothing other than two LED bulbs where one
is grossly overpriced for no reason they can comprehend

~~~
helpPeople
Sell on their website? They get traffic

------
wheels
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_ hard in moving from where I'm from
(southern Texas) to Michigan (for college) and then to Berlin (for the last 14
years). Right now, in Berlin, which is approximately as far north as Edmonton,
Alberta, Canada, North America's northernmost large city, the sun sets before
4:00 p.m.

I usually try to spend a month of winter closer to the equator to keep my
productivity levels and spirits up.

Between the seasonal adjustment (where the sunset time swings by a full 7
hours in Berlin) and my sleep weirdo-ness, I've also come to love me some
artificial-sun-level lighting.

I tend towards 400-500 watt halogen bulbs. I have an up-firing light of
approximately that wattage in every room of my home.

A question for other folks that compensate sunlight with artificial lighting:

Do LEDs really work for you? I'm a wanna-be hippie, and I'd love to use energy
efficient bulbs and have tried every generation of them, but the light just
doesn't do it for me. I keep going back to halogen as the sweet-spot between
black-body radiation and energy efficiency. I can immediately spot the
difference between an LED or CFL and incandescent bulb. I've had some success
in mixing them in about 50/50 ratios. They've already been banned for sale in
the EU, but I have a stockpile that will last me a decade in a pinch. Does
anyone else struggle with the light quality from modern lighting?

~~~
gligorot
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 (town)
changed the street lights to LED's, a lot of people started having sleep
problems, and it supposedly was connected to the blue light emmiting
properties of (lower quality?) LEDs.

~~~
wheels
> _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 original comment, is "black-body
radiation". Stars, fire and incandescent bulbs put out a similarly shaped
spectrum.

A few years ago there were scientists working on a black-body (i.e.
incandescent) light bulb that reflected infrared emission back to heat the
filament and re-emit as visible light making for a theoretically efficient
incandescent bulb. I check every year or so to see if the research has been
commercialized, but have always been disappointed:

[https://www.dezeen.com/2016/01/13/mit-energy-efficient-
incan...](https://www.dezeen.com/2016/01/13/mit-energy-efficient-incandescent-
light-bulb-research/)

Edit: Another point on the blueness of LEDs is that they seem to amplify
macular degeneration, which has made my grandmother mostly blind, and I know
based on gene sequencing that I have a more than 50% chance of developing.
While most of my rejection of LEDs is based on them not looking nice to me, I
am also worried about hurrying the onset of blindness in old age for persons
like myself who carry the genes for macular degeneration:

[https://edition.cnn.com/2019/05/16/health/blue-light-led-
hea...](https://edition.cnn.com/2019/05/16/health/blue-light-led-health-
effects-bn-trnd/index.html)

~~~
marcosdumay
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.

~~~
lahwran
huh that's really interesting about fire's emission spectrum!

regarding 6400k - even assuming the sun's spectrum matched the black body
spectrum of its surface temperature, its surface temperature is closer to
5770k. but even taking that into account, its spectrum doesn't quite match
5770k in space - and the atmosphere changes it even further.
[https://en.wikipedia.org/wiki/File:Solar_spectrum_en.svg](https://en.wikipedia.org/wiki/File:Solar_spectrum_en.svg)

I really don't know how much of that change us humans can perceive, but my
thinking is that 5000k is probably closer to the center, at least. it might be
more of a saturated color, though, since the spectrum is more pointed vs the
very flat but spikey spectrum in that plot.

------
codingdave
> The lamp flickers when other current-hungry appliances turn on

That should not happen. There is likely a problem somewhere in the electrical
system. We used to have similar problems in our home, hired an electrician to
help track it down... they gave our home a clean bill of health, but called
the city... long story short, they found a problem in a transformer a couple
blocks away from us. It had been impacting many homes, and they were shocked
nobody had call it in as a problem before us. But apparently, everyone just
thought, "Oh, flickers are normal when appliances kick on, right?"

~~~
saagarjha
Is it not? I thought the motors inside of them caused that to happen?

~~~
taneq
Yes and no. Motors pull a much higher current when they're starting up than
when they're running, so your wall socket voltage is going to dip when you
start a motor. That said, it shouldn't dip enough to be particularly
noticeable, and if it is then that can point to a problem in your power supply
or wiring.

~~~
kazinator
It might not be noticeable, or as noticeable, with a 150W incandescent bulb,
which has thermal inertia in the filament. What's going on here is that these
are fast LEDs.

~~~
taneq
On the flip side, mains-voltage LEDs generally have built-in power supplies
which should lead to them actually showing less dimming during brief voltage
dips.

~~~
kazinator
Some mains-voltage LEDs in fact flicker at twice the mains frequency! This is
visible when you turn your vision, or when something moving, like rotating fan
blades, is illuminated.

The Phillips flood lights in the track lighting fixture in my kitchen are like
this.

They contain some sort of very light-weight power supply to rectify the line
voltage and adapt it to the LED, but there is no LC capacity in it to even
smooth out the 120 Hz ripple.

There is no room in those bulbs for the electrolytics/inductors that would be
required.

------
BenoitEssiambre
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...](https://www.amazon.com/8T8-Splitter-Standard-Converter-
Commercial/dp/B06ZZ6RY4H/ref=sr_1_1?keywords=8T8+E26+E27+7+in+1+LED+Light+Bulbs+Socket+Adapter+Splitter%2C+Standard+Lamp+Holder+Base+Converter+for+Home+Commercial&qid=1574988239&sr=8-1)

I'd be curious trying a spotlight (something like this:
[https://www.amazon.com/Primelux-8-inch-14400-Lumens-
Driving/...](https://www.amazon.com/Primelux-8-inch-14400-Lumens-
Driving/dp/B01GZST326/ref=sr_1_4?keywords=spotlight+jeep&qid=1574988540&sr=8-4))
that is farther away from me.

The parallel rays of a spotlight would probably look and feel more sun like
compared to the radial rays of normal bulbs.

~~~
Tepix
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.

------
abakker
I’ve got 5 of these in my office.
[https://www.superbrightleds.com/moreinfo/industrial-led-
ligh...](https://www.superbrightleds.com/moreinfo/industrial-led-
lighting/60w-led-retrofit-bulb-for-hid-lamps-7200-lumens-250w-equivalent-
metal-halide-e39-mogul-base-ballast-
bypass-5000k4000k/4647/10374/?redirect_disc=0).

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.

~~~
spectramax
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.

~~~
jrockway
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 close to daylight
in terms of CRI, something like 93 if I recall correctly.

The only thing that makes me unhappy is the current state of LED strip
driving. I have a device that takes 120VAC and turns it into 12V for the light
strips. It "interprets" the output of a triac dimmer in front of it to PWM the
LEDs. Very wasteful and stupid, but there are no constant-current drivers that
just let you use something to adjust the current output unless you build your
own. (A friend of mine did just that; the lights are amazing.) PWM naturally
causes the cheap capacitors in the DC/DC converter to make noise, so I pretty
much never dim them.

~~~
Mountain_Skies
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.

~~~
jrockway
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.

------
jsilence
It is possible to recycle old LCD monitors into articficial windows that have
a very real feel to them. The diffraction lenses for the backlight direct the
light in a way that makes it appear sun like. Of course this is only about the
direction and not about the spectrum, but it might be possible to find LED
strips with a high CRI. Any feedback would be appreciated.

DIY directions on YT:
[https://www.youtube.com/watch?v=8JrqH2oOTK4](https://www.youtube.com/watch?v=8JrqH2oOTK4)

~~~
rickymetz2
Great video. The light produced is so soft and convincing.

Do you know of any consumer version for sale? It feels like there should be a
product offering with how little changes need to be made to convert a tv or
laptop screen

------
derefr
> 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 ancestors spent their days doing?

Consider: many humans were savannah persistence-hunters; but many humans were
_also_ jungle and arboreal-forest gatherers. And either way, we probably liked
to find trees to climb and use as protection, when we could (as chimps do.)

So, given that, are human brains calibrated for "sun-baked African plains"
daytime brightness, or "under a forest canopy" daytime brightness, or
somewhere in between?

~~~
muzani
It could be different for everyone. My ancestors likely grew up in dense
equatorial jungles and caves, not plains. A lot of my family members perform
much better in dim light. My optimal seems to be 2-7 PM on a rainy day.

~~~
honr
I'm not sure about the genetics of it (none of my family members seem to agree
with me), but I also perform _computer tasks_ far better in a dim light. A
friend of me, who is also a night-owl, has the theory that when we get exposed
to daylight, our cavemen heritage's natural reaction is to feel like going
hunting/food gathering. While I don't buy the argument verbatim, I feel more
like doing outdoor/physical activities on sunny days.

------
Mizza
I'm extremely light sensitive, and so have built quite a few DIY solutions in
order to alleviate my S-A-D symptoms.

One of my systems may have been a bit over powered and over used, as I
developed what a doctor friend later diagnosed as "light induced hypomania",
which was quite an experience.

Experiment at your own risk.

~~~
EdwardCoffin
Could you provide specs on this system and clarification on how much use you
believe was too much?

~~~
Mizza
It was tens of thousands of lumens, directly next to computer for at least 8
hours a day. Beat the depression, drove me mad.

~~~
drited
Would you have any pictures? This sounds fascinating (with the caveats you
mentioned of course)

------
milani
> Isn’t using this much power bad for the planet? Coal has a carbon intensity
> of about 1 kg CO2e / kWh (source), so one coal-powered lamp-day produces 2
> kg, approximately one-third to one-half of a cheeseburger (source).

I don't think the author gets a cheeseburger everyday! And even if it is true,
it adds on top of the cheeseburger.

~~~
acqq
And he starts with incomplete data, as only 40% of the energy in coal is
converted to electrical energy. Then, from that 40%, additional 5% are lost in
transmission and distribution, so what reaches his flat is around 38% of that,
or 2.6 kg of coal per kWh.

So one his coal powered lamp day is already, assuming his other factors are
correct, around 5 kg of coal(!) or almost 2 _tonnes_ of coal per year! Which
_is_ a _huge_ footprint. Imagine that the same guy would have to just unload
that much coal, delivered to his house, once a year, and to feed his lamp
every day, would he still consider it "nothing"?

Burning hydrocarbons roughly produces 3 times more CO2 in mass, resulting in
15 kg of CO2 for one of his "lamp days". In volume, it's even more easy to see
the size of that all: a kg of CO2 has volume of more than half of cubic meter
(0.56 actually), so his lamp day produces more than 8 cubic meters of pure CO2
per day or 3000 cubic meters of pure CO2 per year. Enough to fill 25 European
city flats with pure CO2 (otherwise, in atmosphere there's only 0.04% of CO2
-- that's 400 ppm talked about here: [https://e360.yale.edu/features/how-the-
world-passed-a-carbon...](https://e360.yale.edu/features/how-the-world-passed-
a-carbon-threshold-400ppm-and-why-it-matters) ).

"But the atmosphere is huge" \-- yes it is, but still the change of CO2
concentration affects us. There is an experiment that demonstrates the effect
with ink:

[https://www.youtube.com/watch?v=81FHVrXgzuA](https://www.youtube.com/watch?v=81FHVrXgzuA)

We don't see CO2 with our eyes, but the molecules of it efficiently block the
parts of heat emissions (it is just electromagnetic radiation, just like
visible light is) which would cool our part of the atmosphere. So the heat
around us increases, just like it's warmer under a blanket (we are practically
under always thicker blanket, and we add to it with our actions, just like
adding the droplets of ink in that video). Everybody should understand that
much.

------
GuiA
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 dream of a screen that can simulate a
window looking out on any landscape, but these are probably way further out)

~~~
te0006
Have a look at [https://www.coelux.com/](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.)

~~~
natmaka
See also
[https://en.wikipedia.org/wiki/Light_tube](https://en.wikipedia.org/wiki/Light_tube)

------
jamilbk
The main limitation office workers face when working in sunlit environments is
the reflective glare on most, if not all, computer displays.

I conjecture if/when e-ink displays match conventional LCDs in response time
and resolution there will be a movement towards “outdoor offices”.

Imagine being able to work productively in a garden, atrium, sun room, or any
other natural outdoor environment. Many of the pitfalls of indoor, fluorescent
lighting would be diminished. The Bay Area and its relatively fantastic
weather would be fully realized as a perk to tech workers.

~~~
buzzkillington
> The Bay Area and its relatively fantastic weather would be fully realized as
> a perk to tech workers.

I built a Linux box with an rpi3 I had lying around and a boox max3 I got. So
far working out doors:

\+ Insects: you have no idea how many seem to come out of no where just to
annoy you.

\+ Sun: you need sun screen even on overcast days. I look like an overripe
tomato.

\+ Rain: when you least expect it one tiny cloud will go past and drop enough
rain to soak you and any exposed electronics.

\+ Children: loud and obnoxious, seem to be everywhere at any time.

\+ Homeless: turns out they really like parks and assume you're one of them if
you're there for more than 30 minutes.

There's probably more but those are the things I had to deal with yesterday.
Today I just sat on my balcony instead. Sunlight is nice, but there's a reason
why people have been building shelters for millennia.

------
Wistar
Mitsubishi's synthetic-light "windows" announced last year appear to be pretty
spectacular. I want one.

[https://www.bbc.com/news/av/technology-45827812/mitsubishi-w...](https://www.bbc.com/news/av/technology-45827812/mitsubishi-
windows-shine-alarmingly-realistic-fake-sunlight)

[https://www.mitsubishielectric.com/news/2018/0927.html](https://www.mitsubishielectric.com/news/2018/0927.html)

------
keyle
Many offices, mostly in places like Amsterdam, Paris etc. in art-deco
building, take pride in the amount of natural light they're pumping in the
office. With mirrors and sunroofs (with sails as shade) and a few plants, you
can really give a beautiful, open air feeling to your office.

This, feels like crutches.

edit: there is something to be said about starting an hour earlier and
finishing an hour earlier if the sunset is early. It may be a good idea to
live with the natural rhythm of the earth rather than some clock on the wall.

~~~
MiroF
You don't live in Boston, so you don't understand. It's dark by 4-4:15 here

~~~
flypaca
It gets dark in Amsterdam around the same time as well. And Amsterdam overall
gets less sunlight as it is much more north than Boston.

------
Scoundreller
> 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 of heat, you may be able to keep
the temperature of the room you’re in lower without feeling cooler.

The fan is a bummer though.

~~~
morsch
2 kWh is kind of nuts. Yes, it's in the same order of magnitude than the
fridge and washing machine, but those already tend to be the largest consumers
of electricity in a household, unless you're doing cooling or heating with
electrity. And a modern fridge suitable for 2 to 3 persons will be more like
0.5 kWh per day and a load of laundry is < 1 kWh.

~~~
xyzzyz
Three standard 60 W incandescent bulbs will draw just under 2 kWh in 10 hours,
and not too long ago it was completely normal to have many more of these on at
the same time.

------
ZoomZoomZoom
The poor CRI is really a dealbreaker for me. What I've done for my DIY
"ghetto" photography lighting is I mixed 4 led strips of 2 temperatures from 2
different manufacturers. Much better, but still poor, to be frank.

~~~
ta0987
I've been looking at this, but it's not cheap:

[https://www.waveformlighting.com/high-cri-led-strip-
lights](https://www.waveformlighting.com/high-cri-led-strip-lights)

------
Springtime
I'm most pleased with the page's non-Javascript based image comparison slider.
Nice one.

~~~
pimlottc
It didn’t work for me on mobile, and only in a weirdly rendered way on tablet.
I would have liked it if there were just plain image links available.

------
nnq
> Instead of having a strong urge to stop working whenever it got dark out

Lots of us have the _opposite_ urge! My theory is that darkness induces a
combination of _mild-depression_ and _subliminal sort-of-pleasant fear_ that
HELPS us ADD-iacs focus _waaaay better_ especially on tasks like coding and
debugging.

PLEASE never use OPs conclusions when designing public spaces, this would
_kill_ the productivity of people like me!

~~~
dghughes
> ...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.

~~~
nnq
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.

~~~
dghughes
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.

~~~
nnq
then sharing what helped _me_ a lot: (1) forcing yourself to do physical
exercise: running + gym + ~ twice a month mountain hiking works for me, (2)
drop ALL refined sugars (caffeine and other stuff can stay, even some alcohol,
but NO SUGAR!) [after ~3 months of (1) + (2) your brain will be totally
reshaped and waay better performing], (3) _probably the most important:_ build
external accountability - like in make sure there are
friends/lovers/family/clients/employees/etc. that know about your goals like
"study for my CCNA" and will shame you, hold you accountable or even sue you
for failing to do what you said you'll do, (4) meditation (mindfulness) - it's
important to get it that _when you feel the absolute least inclined to
meditate and you couldn 't stand doing it_ is when you most actually need it
and you'll get _the biggest benefit from it_ , and (5) a general more "stoic"
attitude of accepting that "life is pain" and of "learning to love the types
of pain that lead to growth and development"... for me mostly the pain of
forcing myself to finish stuff and to stay-on-track instead of goind sideways
or starting something new again and again.

------
taneq
But I don't want my office to be as bright as the outdoors. I want it to be
dark.

~~~
svd4anything
I’m the same. It is very interesting how people have radically different
experiences with light. I feel the best in winter with cloudy dark days. My
wife is completely opposite and so are most people it seems, they feel good in
sunlight. I’m afraid of it and the summer heat.

------
skunkworker
I’ve recently started buying high CRI LEDs and I’ve noticed a difference in
how the room looks and feels. The older LEDs while can be bright just aren’t
bright in the same way.

------
mmaunder
Light temp is mentioned. It's worth looking at CRI which gives you an
indication of how much of the spectrum is represented. E.g. 18,000 watt HMI
lights for film are tungsten (3200k) and have a CRI of 99 which is insanely
good. But they're 18000 watts. Many high output low watt LEDs have horrendous
gaps in the spectrum.

Unfortunately to test CRI you need a $1500 color meter. I'm lucky enough to
have one and access to a range of film lights and it's crazy how much CRI
varies and the horrendous gaps in the spectrum for some lights.

------
ogre_codes
Do you really need a single mega-light? Seems to me for a lot of situations
having more dispersed lamps would work better and light a room more evenly and
allows more fine tuning of light levels.

------
b0rsuk
I can think of one more potential downside: light polution is bad enough
already. In the author's case, 8x higher lux values. Insect population in
Germany has dropped by about 75% since the 70's. A recent The Guardian article
names light polution a key factor.

In principle, it's possible to shield your windows with thick curtains, but I
know many people won't bother, some will openly boast them, and it may even
lead to more of them being hung outside when people see how great they are.

------
armagon
This is great to see, for I've been wondering lately why being outdoors is
more pleasant (in clement weather) than indoors. Is it the unpredictability?
the humidity? the noises? the sunlight?

In that same vein, I've wondered how to simulate outdoor conditions inside,
especially something approximating more light, in part because I think a
family-member is mildly susceptible to seasonal affective disorder. I can't
wait to see what the author has to say.

~~~
dan-robertson
I’ve also been wondering this lately. In particular if I’m feeling slightly
ill, I feel much better outdoors. At least in my experience, it isn’t
necessarily sunlight as I think it’s also better at night. And it isn’t super
“fresh” air or hearing birdsong or the wind rustling through trees (positive
things I associate with being outdoors) as I live in a city. I hadn’t thought
about humidity. Currently my best guesses are:

\- a correlation between being outdoors and stood up and moving

\- colder temperature (but I guess in the summer when it’s not stifling it can
be preferable to be out so maybe this is wrong)

\- some psychological/placebo effect

\- less CO2 in the air. I can’t really put any numbers to this hypothesis as I
don’t have a meter.

------
m0zg
I've kind of intuitively gravitated towards this ever since energy efficient
bulbs started becoming popular. Instead of buying light bulbs to save energy
per se, I've been buying the highest lumen efficient light bulbs in a given
form factor and color temperature. I prefer 3000K light indoors, and daylight
for working lights. My desk lamps have 100W equivalent daylight "high CRI"
light bulbs. My house lights are basically the highest lumen lights available
in each form factor be it candelabra, "regular" or "fake luminescent". The
light fixtures that do not have light bulbs per se are the highest possible
lumen rating as well. I figure I'm spending less money anyway, might as well
have more light. Unfortunately R30 flood lights aren't generally available in
power rating equivalents beyond 75W incandescent. If some marketing person
from e.g. Osram, Cree or Philips is reading this, could you guys make 150W
equivalent R30 flood light? Charge pretty penny for it, too. I'll pay. I want
punishing light levels in my kitchen/bar area.

------
Jaruzel
> _Isn’t 5000K very “cold” light? “Cold” lights (above 2700k, the typical
> incandescent color temperature) have a bad reputation, but 5000K is actually
> less cold than the sun (which is about 5500-6500K)_

I don't think the author is taking into account that a lot of the blue
spectrum from sunlight is scattered in the atmosphere resulting in a much
'warmer' light hitting us.

------
scotty79
I'm building my own bright lamp recently. I bought 20 Philips bulbs, 1500
lumens each. I attached sockets for them in 5 by 4 array to a 40 by 40 cm
board. I'm gonna attach the board to the ceiling and hang transparent ikea
kitchen cabinet lining below the lamp so it spreads light a bit so it's not
too bright to look directly at it.

It takes about 250W and gives over 10 lux from 1m.

My current setup are two 100W led reflectors pointed at the white ceiling.
Thet give over 200 lux at my desk but are very greenish. It shows up on the
camera (with any whitebalance) and is even slightly visible to the naked eye.

New lamp should be significant upgrade in terms of colors and light strength.
Total cost is around 50$ because I bought lightbulbs very cheap and used
cheapest available sockets, plus few hours of very relaxing work. Reflectors
were even cheaper. Just 20$ and hanging them was less than an hour.

------
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?

------
datenwolf
I'm a little bit worried about the amount of <450nm blue light emitted by
these things. Even if they look warm white, there still might be a very
prominent blue peak. Blue light at about 420…430nm has a very prominent
retinal phototoxicity, and prolonged exposure can lead to loss of vision.

------
iandanforth
I have an LED build-out that was inspired by the Lumenator
([https://arbital.com/p/lumenators/](https://arbital.com/p/lumenators/)).
Since that post 1600 lumen A19 bulbs have gotten much cheaper and so I run 9
of those in a 3-fixture tree lamp with 4-way spliters.

I also experimented with commercial string lights and ended up hanging one
strand with around a dozen bulbs over an ikea pyramid coat rack behind a
Japanese style paper screen and that made for a bright and beautiful standing
lamp.

I also found that having a timer/dimmer was a great way to wake up in the
morning. Much better than any alarm, but if you don't sleep alone you need to
get your partner on board.

I highly recommend trying a build for yourself!

------
RoboTeddy
Anyone know a way to set up lighting that is (tiers of priority):

Tier 1:

* high-CRI

* high-lumen

* dimmable, and can be set up to turn on slowly in the morning

Tier 2:

* not glary

Tier 3:

* easy to install

* inexpensive

* power efficient

------
quartus
This immediately reminded me of the scene from Silicon Valley where Gwart is
working directly in front of an extremely powerful light, which Jared rushes
to shut off because it's too bright

------
logicallee
This is a pretty big claim:

>The effect was huge: I became dramatically more productive between 3:30pm and
whenever I turned off the light. Instead of having a strong urge to stop
working whenever it got dark out, I was able to keep working my normal summer
schedule, stopping just before dinner. I estimate the lamp bought me between
half an hour and two hours a day, depending on how overcast it was.

Does anyone know if people really do become "dramatically more productive"? It
should be something that could be tested...

------
jmartrican
I use a flood-light bulb in my torch floor lamp (pointing up to the ceiling).
This fills the space with a lot of light without having a bright spot that
cannot be stared at.

------
kragen
There are a bunch of calculations about this in Dercuano, in particular based
on indoor-growing setups, but with a chair in them instead of a plant pot. It
turns out that fluorescent tubes or especially halogen bulbs are cheaper than
LEDs, and at the small scale of a desk and chair, the extra energy is
affordable.

One big problem for hackers is that very few screens are readable even in
10klux, let alone 100klux direct sunlight (although that has the disadvantage
of burning you).

~~~
exikyut
What about transreflective displays?

Annoyingly I've _still_ not seen one IRL. They go black and white, apparently,
but are still 100% legible.

~~~
kragen
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 with them are much
more easily available, but most of them only come in the surveillance-
capitalist hood-welded-shut model. They use orders of magnitude less energy
than transflective LCDs for some usage patterns, but refresh slowly.

~~~
jasonmp85
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.

~~~
kragen
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.

------
therealdrag0
I like natural light, but office ceiling lights hurt my eyes.

------
ferros
I always feel better with bright lights and have considered trying something
like this before, however two things always stop me.

1) Concerns about eye damage.

2) Concerns about skin damage.

~~~
sojmq
I was thinking about that. Putting a microsun in your peripheral vision? Can't
that mess with your eyes in the long run?

~~~
mcv
I strongly, strongly prefer indirect light.

------
mcv
I don't really need this, but if I did, the fan would probably be a deal-
breaker for me. Instead, I'd spread this out of multiple weaker light sources.
That would spread the light out more, spread the heat of course, and probably
also make it easier to tune it to exactly the light level you want.

I do understand the desire to have daylight-level lighting in your house. It's
a shame it takes so much power.

------
hereme888
I'm planning to move to northern Alaska in a few years, so this information is
very welcome.

I know I will need a setup against S.A.D. because it's very real up there.

If I get 4 of the 120 watt fanless bulbs, the daily cost of the bulbs and
running them 8 hrs/day (assuming 30,000 lifespan) would cost only ~$0.29/day.
That's an easy choice against SAD.

------
asdf333
i have seen articles about excessive blue light from led bulbs being bad for
your long term eyesight

i wonder if this has similar problems

~~~
knzhou
It can't be much worse than being under the _blue_ sky.

~~~
ta0987
The blue sky's spectrum doesn't have a giant spike like this:

[https://www.benkuhn.net/img/lux/ledspec.png](https://www.benkuhn.net/img/lux/ledspec.png)

~~~
knzhou
Yes it does! A giant spike in the blue region is literally what makes the sky
blue in the first place. If there weren't such a spike the sky would be white.
When you look up at the sky on a typical clear day, you're getting more blue
light than almost any one of these indoor setups.

~~~
ta0987
I see your point, I was thinking of daylight in general. But even the blue sky
is not quite as spiky:

[https://en.wikipedia.org/wiki/Diffuse_sky_radiation#/media/F...](https://en.wikipedia.org/wiki/Diffuse_sky_radiation#/media/File:Spectrum_of_blue_sky.svg)

If you look at 460-470 nm where the spike is in the LED spectrum, it's much
lower in the blue sky spectrum.

I think the concern is something about the relative amounts of blue light. Not
sure what exactly but something like, the human perception of brightness and
therefore the self protection of the eye is calibrated for natural light, so
the pupil contraction, looking away, etc, is not done correctly in with that
unnatural distribution. Anyway I don't know if that's a real effect, but
that's what people (should) mean when they're talking about "too much blue".

------
amluto
> But as of recently, it’s totally practical to fill your entire house with
> light that’s as bright as full daylight.

If you actually get your house as bright as sunlight, that means you have ~1kW
/ m2 of light in your house, which is impractical no matter how cheap and
efficient LEDs get.

~~~
Const-me
It's 445W/m^2. More than half of these 1kW is infrared.

------
philip1209
I have a one-person office with glass walls in a coworking space. I've been
looking for a lighting option that could possibly go above or below my
monitor. I like the bulbs in this article, but I would prefer something
directional so that I don't disturb my neighbors. Any suggestions?

~~~
benkuhn
If a 120-degree cone is good enough for you, try searching for "high bay
lights"? E.g.:
[https://www.amazon.com/s?k=high+bay+lights](https://www.amazon.com/s?k=high+bay+lights)

If you're willing to pay more for much better color rendering than mine, my
coworker got excited about these:
[https://store.yujiintl.com/collections/high-cri-led-
lights/p...](https://store.yujiintl.com/collections/high-cri-led-
lights/products/high-cri-95-high-bay-ufo-led-light-pack-1pcs)

Note that it's 1/3 the lumens of my corn bulb, but the smaller angle means the
lux may be about the same (or you might need more--I haven't tried these).

------
JohnJamesRambo
Actual outdoors light levels are much higher than 600 lux. More like
50,000-100,000 lux.

[https://www.royalqueenseeds.com/blog-how-to-use-a-lux-
meter-...](https://www.royalqueenseeds.com/blog-how-to-use-a-lux-meter-to-
increase-your-cannabis-yields-n977)

------
anotherwebdev
I built my own lamp for that and it cost me roughly the same. It's best to use
metal-halide lamps as their spectrum is very close to the Sun's. It's
important to get one with a uv filter though.

------
nnq
> stop working whenever it got dark out

Also, this might be a _good_ urge - just stop working and stop trying to use
light to squeeze every ounce of productivity from yourself until you burn out!

------
DenisM
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.

~~~
tzs
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 household items,
like a Pepsi can, a plastic bottle of Tide detergent, or box of Arm & Hammer
baking soda. If the app included a reasonably good sized database of such
items, there would be a good chance an average user would have a suitable set
of color references already on hand.

~~~
DenisM
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.

------
dghughes
> Why doesn’t everybody do this?!

Because I am more productive when it is dark or overcast. I get nothing done
when it's bright.

I struggle to focus during the day and become more productive when it is dark.

------
paulmendoza
I put a bulb like this only in my office. Has helped tremendously although you
notice the difference in light color between it and the other lights in the
house right away.

------
cryptozeus
Any recommendations for spotlight table lamp in the office ? Looking for
something when studying or working with room lights off and have only table
lamp on for focus.

~~~
Marsymars
Kind of depends if you want something with integrated LED, something where you
can screw in your own bulb, controls for dimming, what type of bulb, etc.

Personally I like the Ikea Forsa.

------
sveme
Any suggestion for smart light bulbs that work without the cloud? Don‘t want
to have the server shut down in five years when the bulb still has 15 years in
it.

~~~
flo123456
Basically anything that can be flashed with open firmeware, such as Tasmota
([https://github.com/arendst/Tasmota/wiki/Prerequisites](https://github.com/arendst/Tasmota/wiki/Prerequisites))
plus a local instance of Homeassistant. It needs a bit of work and sometimes
soldering skills, but some devices can be flashed without soldering and in
general it’s not too hard to do. :-)

------
0x262d
this is a cool idea, but, the "is this bad for the planet" question seems like
it's saying it isn't, but the comparison seems to indicate that actually it's
quite bad for the planet, like very bad as far as lifestyle choices go? not to
say that alone makes it a bad idea to do, but that a sane society would make
buildings that capture and use more sunlight from the actual sky.

------
reportgunner
Rooms can even be brighter than the outdoors you know.

------
gHosts
A colleague points out that the COB rather than SMD based lights have a better
spectrum.

~~~
anotheryou
why though?

------
mangecoeur
> isn't this expensive to run

comparing lighting to the consumption of a fridge, which is one of the most
energy intensive appliances in an average house, is kinda ridiculous. Its like
saying your lawn mower energy use is just fine because it consumes the same as
your SUV.

Tl;dr: 2kwh per day for a light is a LOT. A standard led light would consume
about 5% of that.

~~~
TheCoelacanth
Three incandescent light bulbs that would have been standard 10 years ago
would consume as much energy while putting out far less light. It's not a
crazy amount of energy, standard LED lights just use so little energy that
it's hardly worth measuring.

------
jan6
text: _fluorescent vs. an incandescent_ the graph below: fluorescent vs. _LED_

which is it? ;)

------
flashman
please do a follow-up on the affiliate revenue from this article

------
doctorpangloss
> For instance, cancer progresses much faster in summer than in winter [edit:
> cancer progresses much faster in constant light: winter vs. summer is
> complicated]

I don't know you, you make a very successful app that people really swear by.
I have no qualms about people using f.lux, if you want to take your $4,600
laptop and $1,400 phone, on which people spent decades perfecting color
reproduction, and you're paying $13/mo for Netflix to watch shows with multi-
million dollar budgets and dedicated colorists, and you start watching Orange
is the New Black and you make it yellow, that's your prerogative. So you don't
need my opinions, so don't downvote just because you like f.lux and hate
opinions.

Why did you have to say anything about cancer at all?

What's your personal line for, "I'm not sure" versus "This is actionable
evidence for change in behavior?"

There is no clinically controlled evidence showing that interventional blue
light, the kind that would be emitted from an LED, causes significant change
in sleep quality with measures like minutes spent sleeping or an insomnia
scoring system. I found this by searching "blue light" and "sleep" in
clinicaltrials.gov. There are 4 or 5 studies on the matter, all negative
results. The best way to interpret this evidence is that blue light will not
make you sleep less or experience insomnia more.

Indeed, if you consulted a doctor, you might learn that waking up too early is
the most common sleep disturbance in adults. This interferes with their daily
lives, by causing them to feel drowsy in the middle of the day. That's why
blue light is typically investigated as an intervention: to get people to fall
asleep and wake up later. It just doesn't turn out to work for that. Its
absence is not causing people to fall asleep earlier either.

~~~
errantspark
I'm just commenting to save what might be the saltiest comment I've ever seen
on HN. I bet you're very fun at parties.

~~~
maxerickson
You can directly save comments by clicking on the timestamp. Then click
"favorite".

~~~
saagarjha
Favorited comments show up publicly. You may not want to appear to exclusively
enjoy barbed comments.

------
mathnode
It's a lovely article; in substance and style. I purchased a very cheap (£50)
win10 tablet a few years ago, and content like this makes me very happy.

