Seriously bright light vs. winter blahs

Antique postcard of a sunny beach scene

Bright lights can chase away the winter blahs. You may need a lot of light—more than you can get with ordinary bulbs, or with a “light therapy lamp.” Here’s practical ways to make your space feel like a summer day when it’s dark outside.

It’s five p.m. in late November now. It’s been a gloomy day, and it is completely dark outside. I am working in a room with very bright lights spaced evenly around its periphery. It looks and feels like a sunny May afternoon in here. I feel great, and I will write productively until 8 p.m. Before I discovered sufficiently bright lights, I would be miserable and useless at this time.

This is the second of two web pages about bright light supplementation for improved winter mood and productivity. The first page, YOU NEED MORE LUX, explained how and why bright light works, and how to make it work for you. It also explains why most lights sold to treat seasonal affective disorder probably won’t work for you: they are no brighter than a single regular household lightbulb.

This page explains how to get actually bright light, in practical terms. Currently, that is possible only using industrial lighting solutions, typically used for lighting warehouses, parking lots, and football stadiums.

The first half of the page, “Ways to get much more light,” begins with relatively inexpensive options that require no effort to set up. You can just order them off the internet and put them on your desk.

Then it discusses better, brighter options that cost more. These include bigger bulbs than you can get at your hardware store, and flat panels a couple feet across. In some cases, these require basic tool use to install.

The second half, “What to look for when shopping for light supplements,” explains how to choose. LED lighting technology has improved rapidly over the past several years and probably will continue to. Although the first half makes some specific suggestions for products to buy, those may not be available next year, or there may be better alternatives. The second half explains what features make LEDs suitable for winter light supplementation. These will probably not change in the next several years.

Ways to get much more light

This half of the page discusses four approaches:

I don’t provide detailed individual product reviews, because available products change more frequently than I’ll update this page, and because I don’t want to do the detailed work of testing and comparing a dozen similar things. I do link particular products on Amazon, as a convenience for readers, but these aren’t recommendations for them over similar ones from other brands. (Amazon sends me a couple dollars per day in return, via their Associates program.)

This page assumes that you have been inspired by the previous one to experiment with brighter light than is provided by standard light therapy lamps. As that page said, there is currently no scientific evidence that this will work. So, nothing here should be taken as medical advice; proceed at your own risk. That said, summer sunlight is still brighter than you are likely to be able to achieve artificially, and presumably sunlight does not cause you trouble. Still, I’ll point out a couple of particular possible risks. First, even standard SAD light therapy can trigger hypomania or mania. If you know you are prone to either, consult a mental health professional first. Second, consult an ophthalmologist if you have, or are at risk for, any eye conditions such as macular degeneration.

Since this is experimental, I encourage you to report your experiences in the comment section of this page. We’ve had many lively discussions there, over nearly a decade. (This page has changed radically over that time, as I’ve revised it for new lighting technologies, so some earlier comments may lack context.)

The two easiest starter solutions

The most important thing is to do something. If it’s already past the equinox and the winter blues have set in, it may be hard to do anything. Light deprivation makes everything seem too complicated, and too much of an effort.

So I’ll suggest a couple things you can do that are simple, minimal effort, relatively inexpensive, and will probably work. These are not the best things. They’re enough for you to see that very bright light can make a significant difference.

Once you have experienced that, you may be motivated to put more effort and money into more powerful alternatives. Or, if you are already persuaded, you can skip ahead to those.

I’ll suggest two ways to get started that don’t require any thought or physical assembly. You can just order them off the internet. Either you could buy the most powerful thing sold specifically as a SAD lamp; or you could buy a couple of industrial LED bulbs that together put out more light than that for much less money. I recommend the second, mainly for cost reasons.

You could get something recommended by supposed experts

In “YOU NEED MORE LUX”, I recommended against buying anything sold as a “light therapy lamp” or “SAD lamp” or “light box,” because they are overpriced and underpowered. However, you may be more willing to take the advice of the accredited experts who advocate them than some internet eccentric (me). I discussed their recommendations here.

Their #1 recommendation until recently was the Northern Lights “North Star 10,000,” which duplicates the light boxes used in the original research on seasonal affective disorder. It is definitely powerful enough to be effective (which most SAD lights aren’t). Its main drawback is that it costs $334 (as of late 2023). You can get more light for $100 using simple LED bulbs (as I’ll explain in a minute).

$334 may seem like too much, which may be why the supposed experts have recently switched to recommending the “Carex Day-Light Classic Plus,” currently $144. I specifically disrecommended that, because it’s underpowered and overpriced.

The experts do agree with me that any “light therapy lamp” less expensive than that isn’t powerful enough to do the job. But you can spend less than $144 and get much more light another way…

More light for less money

My better starter recommendation is to get a pair of daylight white 100W LED “corn bulbs.” There are many brands of these available on Amazon and elsewhere; I got this one. Two of these produce more light than the North Star light box. You can put them in any regular lamp that’s rated for 100W or more, if they fit. They are much bigger than a regular bulb; I put mine in this lamp base, for a total cost of under a hundred dollars for the pair.

If you put these on either side of your laptop, you’ll know what actually bright indoor light means—something you have probably never experienced. These bulbs are 100 LED watts each; together they are roughly equivalent to 2000 watts of incandescent bulbs.

Two 100W LED bulbs behind and beside a laptop

They should be reasonably close to you—eighteen inches to two feet from your eyes. Try one on either side of your workspace, just behind what you are reading so they don’t swamp it. If you can, put them above eye level. Do not look directly at them; let the light enter your peripheral vision as you look at your book or screen.

You will probably find that using them makes you markedly more cheerful and productive. This may take effect rapidly, possibly even within minutes of first use, although the usual story is that you need to use a SAD light for a couple weeks to get relief. (Maybe that’s because they are badly underpowered?)

As I said, this is not an ideal solution. One reason is that you will probably find them unpleasantly glare-y. They do need to be too bright to look at—like the sun, which they’re simulating. This is not the way we’re used to relating to indoor lamps. Once you get used to it, very bright light is extremely comforting in winter.

I have found the glare, when in peripheral vision, mildly unpleasant. It’s tolerable though, and definitely worth it for the mood-lifting and productivity-enhancing supplement effect. If you don’t mind a bit of craft work, you could rig “diffusers” to cut the glare and spread the light out. There’s special cloth for this purpose used by photographers, or you could try a sheet of translucent plastic.

You will probably also find that lighting up a small area, leaving the rest of the room comparatively dark, feels unnatural. That’s clear in the photo above. The shadows around your little pool of brightness may come to seem slightly creepy.

You will probably soon realize that having bright light just in one place is not as much as you want, and the idea of having your whole room evenly bright, without glare, becomes excitingly attractive. That’s what the rest of my recommendations are about.

This is what the same scene shown above looks like when it is completely dark outside but the room is lit with 1200 watts of additional LEDs spread around its periphery. Much more inviting, isn’t it? The little 100W LEDs are not necessary at all, although they are turned on just as brightly in this photo as in the previous one.

Workspace fully illuminated with bright LED light

Corn bulbs: easy, versatile, incremental

In the previous section, I recommended starting with a couple 100W corn bulbs. That’s enough to be effective, but only if you keep them quite close. I suggest that lighting up an entire room is much more pleasant. It means you can move about, there aren’t dark corners, and the light is diffused and can come from above, which is much more natural-feeling.

Lighting up a room that brightly will cost you a few hundred dollars, which might seem like a lot for light bulbs, but it is totally worth it if it makes you cheerful and productive in the winter—as it did for me.

The easiest way to accomplish this is with more, bigger corn bulbs. As of 2023, they go up to 450W, but 240W ones are the most cost effective in terms of light output per dollar. Generally, high-wattage LEDs are all roughly equally efficient, so comparing watts is nearly equivalent to comparing light output. A 240W corn bulb puts out just about 2.4 times as much light as a 100W one.

Corn bulbs have several advantages:

Relative to LED panels—discussed in the next section—corn bulbs have some disadvantages:

240W corn bulbs are much larger than ordinary bulbs, so you can use them in some ordinary lamps, but you need to be sure there’s room. They’re also somewhat heavy, so you want to choose lamps that won’t tip over. They won’t fit inside typical lamp shades, and also produce a fair amount of heat, which might be a fire hazard, so you will probably want to remove the shade from whatever lamp you use.

Corn bulbs above 100W also usually have a bigger screw base than regular household bulbs. You can either use an inexpensive adapter, or a socket of the larger size.

Regular household bulbs and lamp sockets are size “E26” in the US and other places that use 110V electricity; they are size E27 in Europe and other places that use 220V electricity. The larger ones are E39 (also called “Mogul”) in the US, and E40 (“Goliath”) in Europe.

An inexpensive adapter lets you use a big E39 or E40 bulb in a normal E26 or E27 socket. This is safe so long as the socket is rated for at least as many watts as the bulb.

Here’s a 240W corn bulb, with the adapter, in a torchiere. This may be the easiest way to use one. I got the torchiere for $29 at Home Depot; unfortunately that particular model is discontinued, so you’ll need to find a different but similar one. [Update: Apparently torchieres rated for more than 150W per socket are now entirely unavailable. 150W LED is still a lot of light, but this may be a less attractive approach than previously. A plausible alternative is to use a compact corner shelf (such as this one perhaps) as a stand. Then you can put a 240W bulb in one of the lamp bases I recommended earlier—those are rated to 300W—using the E39/E36 adapter, and put that on the top shelf. As of December 2023, I am investigating additional alternatives.]

A large LED corn bulb in a standing floor lamp

I’ve bought several different brands of corn bulbs, and they’ve all been fine. In late 2023, 240W ones cost about a hundred dollars. DragonLight is a reliable mainstream one, and is the one shown in the torchiere photo. Most recently I bought this “NS” brand one, which cost less and has been fine so far, although it is less attractive and bulkier than the DragonLight. If you are feeling a bit adventurous, similar bulbs are available at about half the price on Ali Express, an eBay-like marketplace in which Chinese companies sell internationally. Orders generally take a couple weeks to arrive, and what you get might not be exactly what you expected, but it’s basically legit.

Another easy way to use corn bulbs is to hang them from a rail, wall bracket, or the ceiling. A “hanging lantern cord” has a socket at one end, a plug at the other, and often a switch in the middle. Here’s a 100W corn bulb in an E26 lantern cord and a 240W one in an E39 lantern cord. For an E39 bulb, you could also use the adapter and an E26 cord, but the E39 cord has a hanging bracket that takes extra weight.

Larger and smaller corn bulbs hung from lantern cords

Depending on where you want the light, you might ideally want a type of lamp that’s not commercially available. If you are handy and enjoy simple construction projects—like I do!—you can create something specific to your needs.

Back in 2015, I built a lamp fixture—photo below—to go above and behind my computer monitor.1 The most powerful corn bulbs then were 100W, with E39 bases. So I built the lamp with three E39 sockets, and an aluminum reflector behind the bulbs to direct more of the light forward.

Homemade SAD lamp with three corn bulbs, behind monitor

Here it is without the monitor, so you can see more clearly what I did:

The same SAD light without the monitor

I’ve found that 300W is about right for this use; I’d go to 400W if I were making another now. I probably also wouldn’t make something, but would just buy inexpensive desk lamps capable of taking corn bulbs.

In 2015, these 100W bulbs cost $120 each and were as big as 300W ones are now. I expect this trend of improvement to continue.

LED panels: brightest, best cost/watt, may require some DIY

Flat LED panels are used for overhead lighting in warehouses, parking lots, and stadiums. As of 2023, they go up to 800W, so one or two can make a room plenty bright. They are less expensive than corn bulbs for their light output, and since all of it gets directed forward, none is wasted. If you can install them without too much hassle, this may be the currently best approach to bright light supplementation.

Panels come in different shapes for different purposes and pose different mounting issues.

Warehouses use “UFO high bay” lights:

This brief video gives a really nice sense of what UFOs look like and how to install them:

Andy Scott in this twitter thread shows another possibility, mounting one on a photographer’s stand.

I have not tried UFO lights; let me know how they go for you if you do!

In a different format, I have been using this 600W stadium light for the past three winters. It’s a bit over $200 on Amazon as of November, 2023. It’s 600W, which is enough to make a small home office bright enough for me. I’d want two for a larger room. I’ve used it heavily and it’s been trouble-free.

The price of that particular product has been stable for three years, while LEDs generally get less expensive every year. Here is a newer one that is 800W, also for a bit over $200; I haven’t tried it.

These lights come with a mounting bracket, which I originally screwed onto an exposed wooden ceiling beam. That was quick and easy. Then I moved to a different place where I couldn’t drill into the ceiling. I mounted it in a wire shelving unit I got at Home Depot:2

Stadium light mounted in a shelving unit

I wrote about two ways you can wire it up here and here.

What to look for when shopping for light supplements

Specific LED product recommendations become obsolete rapidly, because what’s available keeps changing—for the better each year. So this half of the post explains criteria for choosing. These guidelines should hold true for years to come.

Brightness: lumens, watts, and “equivalent watts”

My overall theory is that more light is better, and specifically that much more light than SAD therapy lamps provide is much better than a therapy lamp. So getting enough light for as little expense and hassle possible is the first criterion. What kind of light you get also matters a lot, and we’ll consider that after this.

Lumens are the unit of measure of how bright a lamp itself is—how much light it produces. Lux are a measure of how much light you get. These are not the same; the further you are from a lamp, the less light you get. Converting one measure to the other is not straightforward; it depends on how close you are, and how much of the light is directed toward you (vs. away in other directions) .

To light the whole of a medium-sized room, brightly enough for me, takes about 100,000 lumens. This is based just on experience, not any theoretical calculation. Since people seem to differ in how much light they need, what is right for me may be more, or less, than what’s right for you.

I haven’t measured it, but I think the 100,000 lumens probably provides significantly less than 10,000 lux in my office. (10,000 lux is the recommended dose for SAD treatment.) However, for me, lighting the room this way seems significantly more effective than 10,000 lux from a light box. I suspect this is due to the peripheral vision effect I discussed earlier. The daylight sensing cells are spread over the whole retina, so illuminating your whole visual field, even with somewhat less light, works better than concentrating somewhat more light in one corner.

Many industrial lights specify how many lumens they put out; the stadium light I described above is rated 48,000 lumens. (So I might want two; but one is a good start.)

It is probably easier to think about LED power in watts than in lumens. All LEDs are about equally efficient in how many lumens they produce per watt; it’s roughly 100 lm/watt. (“lm” is the abbreviation for lumens.) So a 240W corn bulb produces about 24,000lm, and a 100W one produces about 10,000lm, and it may be easier to think of 240/100 than 240,000/10,000.

More powerful LED lights are somewhat more efficient in how much electricity they consume per lumen. They’re also generally less expensive to buy per lumen, or watt.

Household LED bulbs output about 70 lm/watt, versus typical industrial lights at about 100 lm/watt. Some high-watt bulbs and panels claim as much as 160 lm/watt. I’m somewhat skeptical of this, although still higher efficiencies have been shown possible in the laboratory.

Unfortunately, many products do lie about how bright they are, or how many watts they draw. There’s many credible Amazon reviews that say “this product was dimmer than I expected, so I measured it, and they exaggerated the output by 50%.” I’ve avoided such products, but when buying you have to just accept some risk of this, because there’s no independent testing. Manufacturers with an established reputation may be less likely to lie; and if a product is dramatically cheaper than similarly-rated ones, it may be more likely fraudulent.

Throughout my discussion, I’ve taken advertised specifications at face value, because there’s currently no alternative.

Also, watch out for “equivalent watts.” LEDs are often sold in terms of how bright they are compared with some other sort of bulb. For example, in a hardware store, you’ll see household LED bulbs sold as “75W” that are approximately as bright as an old fashioned 75W incandescent bulb. In fine print, the package says that’s “75W equivalent,” and it’s actually a 12W LED. A 75W LED is quite bright; a 12W LED is… as bright as a 75W incandescent, which is to say quite dim. High-wattage industrial lights are, similarly, often labeled with watt equivalents of the earlier industrial lighting technologies (HID, HPS, MH, CFL) they replace.

Color temperature is critical; you want about 5600K

Simplifying somewhat, “color temperature” tells you how much blue there is the light. This is critical, because only blue light triggers the system your body uses to tell that it’s daytime. (I explained that here.) You want plenty of blue light during your simulated daytime of 12+ hours, which keeps you alert and engaged. You want to avoid blue light past your simulated sundown, around seven or eight p.m. for me. Blue light after that tells your body it’s still daytime, which messes up your circadian rhythm and makes it hard to sleep. (More about that here.)

Color temperature is measured in K.3 Actual daylight is 5600K. “Daylight white” bulbs are between 5000K and 6000K, and that’s what you want; it has the right amount of blue.4 Sometimes “cool white” means that too; sometimes it means more than 6000K, which will work, but may look unnaturally blue.

“Warm white” (3000K) is probably not effective for preventing winter blahs, and “neutral white” (4000K) is probably significantly less effective than daylight white.

You should use normal, non-bright residential warm white bulbs for your regular house lighting, and switch to those at your artificial dusk time.

Color quality may matter; I don’t know

White light, you may recall, is a mixture of all colors. However, quite different amounts of different colors can add up to “white.” For example, “white” could include much less blue-green light than daylight if there’s more blue and more green—and typical LEDs do exactly that. This matters if you are an artist, because blue-green paint will look duller under LED light than under daylight.

It may also matter because the daylight-sensing cells in your retina are most sensitive to sky-blue light, which is somewhat greenish, and less sensitive to deep, royal blue light, which typical white LEDs produce more of than daylight.

Higher quality LEDs produce ratios of individual hues closer to daylight than typical LEDs do, and that may make them better for bright light supplementation.

Color quality is usually specified as “CRI,” the Color Rendering Index, which goes up to 100. Most white LEDs are rated 80 CRI. “High CRI” is a meaningless marketing term that can mean anything upwards from 80. 90 CRI corn bulbs are not much more expensive than 80 CRI, but are much less different than the numbers would suggest.5 Genuinely high CRI is 95 or more.6

Bulbs in the 95+ CRI range are much more expensive; several times the price of ordinary LEDs of the same brightness. On the other hand, maybe the better quality means you don’t need as many lumens.

I haven’t experimented with these, due to the cost. Some friends say the light feels better, and is worth paying for. Whether it would make enough of a difference for me, or for you, I don’t know.

A friend recommends this 40W CRI 95 corn bulb ($35 in December 2023). 40W seems to be as high as CRI 95+ corn bulbs go currently.

If you want brighter high-CRI light, professional video production lights are the way to go. These have several significant advantages:

The disadvantage is that they are much more expensive per watt than lower-CRI corn bulbs or panels. However, prices are falling for these, as with all LEDs, and you may find them affordable now, or in the near future.

GODOX and Aputure are well-regarded professional brands. In 2023, my casual Amazon search turned up this one, which is 190W, 5600K, CRI 96, for $175. Nick Cammarata on twitter recommends this one, which is 1200W, tuneable color temperature, and CRI 96. It costs almost $3500, which is sadly out of my price range. (By the way, if you would rather avoid Amazon, you can buy video lights at B&H Photo, a highly reputable supplier to photographic professionals.)

High CRI, although pleasant, may not be optimal for supplementation. Maybe light with more sky blue in it than natural sunlight would be more effective at a given brightness level. There’s been one clinical test of this, which found that sky-blue enhanced LEDs did work better than standard ones (yay!), but the effect size was quite small (oh).7

There is a commercial product based on this hypothesis, the Chroma Sky Portal. I know people who use and recommend it. I don’t know of any testing of its effectiveness versus equivalently bright standard LEDs, which are much less expensive.

Aesthetics

No industrial light is going to go well with your home decor (unless you are into the industrial look, in which case, wow, get some UFOs!). No light made for home use is bright enough (for me).

This may change; I’m certainly not the only one who wants genuinely bright home lighting. I won’t be surprised if, in ten or twenty years, it’s normal to have 100,000 lumens pre-installed in the ceilings of the living rooms of newly-built houses.

Flicker

Some people find LED flickering bothersome. I can’t see it. (My spouse can, but isn’t bothered by it.) The amount of flicker apparently varies between lights, but it’s not specified, so I don’t know how you could choose low-flicker ones.

Durability/reliability

Amazon reviews often complain that an LED light failed soon after purchase. I’ve had this happen this only once (out of about a dozen high-wattage lights I’ve bought). It was a panel that was dramatically less expensive than alternatives. I don’t know of any way to avoid this (other than reading reviews, which are not always reliable themselves).

Heat dissipation and fan noise

Bright LED lights generate quite a lot of heat. A few years back, many had noisy fans to deal with that. Others didn’t deal with it well—in which case they could be a fire hazard, and also overheating sometimes caused them to burn out.

The manufacturers now have this under control; none of the several bright LEDs I’ve bought in the past few years have audible fan noise, and they don’t get dangerously hot.

  1. 1.The original version of this web page was just about how and why I built that computer monitor lamp!
  2. 2.Jess Reidel came up with the same solution independently!
  3. 3.K here is for kelvin, which is a unit of temperature. Rather confusingly, “cool white” light has a high color temperature, and “warm white” light has a low color temperature. This is because of some physics that is interesting but not relevant here.
  4. 4.Color temperature is not a perfect measure of how well a light stimulates your eye’s daylight detectors. Two bulbs with the same color temperature may contain somewhat different amounts of the necessary wavelengths. For a summary of relevant research research, see for example Allison Thayer’s “Industry must move beyond CCT to articulate circadian metrics.” (CCT is “correlated color temperature.”)
  5. 5.There’s a useful interactive visualizer at https://www.waveformlighting.com/high-cri-led; scroll down to the “Compare our spectral power distribution” section and try pushing the daylight, 99 CRI, 80 CRI, and 90 CRI buttons there.
  6. 6.CRI is not a great measure, especially at the high end. There are several alternative measures; you may see “TLCI,” the television lighting consistency index.
  7. 7.Eo et al., “Development and Verification of a 480 nm Blue Light Enhanced/Reduced Human-Centric LED for Light-Induced Melatonin Concentration Control.”