superchiasmatic LED light insomnia

For most of the summer my Spouse has had insomnia. The degree has varied, but pretty much about 1/2 the time she was not sleeping enough (or at all) and the other half was not “restful” in that deep regenerating way.

I’d noticed that she was up much later than normal, but had not been informed about the depth of the problem. Her normal day ends at about 9 pm to 10 pm. In bed, gone to sleep, and waking up spontaneously about 5 AM. Sometimes in hours starting with a 4… Me? I can be awake any time the moon is overhead (especially full moons) and have been known to climb into bed just as she is waking up.

So both being awake at 11 pm to 1 am is a bit, er, unusual. I’d just noticed a bit of unusual. Two days ago I was “brought up to speed” on things. That sent me off looking for causes (ever the “Fix The Problem” guy…) One factoid to note: I had done the ‘seasonal bulb change’ from incandescents to high efficiency with the arrival of warmer weather; but this time I had bought a couple of more LED bulbs. Slowly adding to the inventory in use. Transitioning from CFL ‘curly bulbs’ to LEDs now that the price of LEDs was in the $10 range and the PG&E subsidy of CFLs had ended (with the ban on incandescents, who needs to care what you chose any more?…) they were closer in price and I liked the ‘whiter’ light of the LED along with the ‘no mercury’ feature.

So one natural question was just “could it be the lights?”. SWIMBO has seasonal affective disorder if she does not get some added UV during the deep of winter, so is a bit more sensitive to her lighting environment than I am to start with. Could it run both ways? But what WAS the spectrum of LED bulbs, anyway? I knew some of them used UV LED chips and phosphor, so might it have something to do with that? That was my first thought, anyway.

On digging into it, I found that most LED bulbs do not use UV. Most use BLUE light, and then just downshift some of it to the green / yellow / red bands to make a generally ‘white’ light source. Hmmmm…. Blue…. I remembered reading something about blue light and Jet Lag a year or two ago…. Folks had found that BLUE of a certain range reset your Jet Lag, so you could get these little glasses that shone a blue light, an LED light, into your eyes while flying to keep you “up” and adjusting your clock to the daytime at your final destination.

Could it be that simple? Could this be a case of The LED Blues? Literally?

A few more minutes of web wandering brought up a very useful chart. From the Wiki on LED lighting:

LED "white" light spectrum from Blue LED + phosphor bulb

LED “white” light spectrum from Blue LED + phosphor bulb

Original Image

Notice that big spike at about 460 nm? That’s the blue that resets your biological clock to “daytime now”.

Until the 21st century, scientists only knew of two types of light-sensitive cells in the eye: rods and cones. But in 2001, David Berson from Brown University established that the eyes of mammals contain a third type of cell for absorbing light.

“This has been a very exciting discovery in the whole world of chronobiology and vision research,” said Jay Neitz, a professor of ophthalmology at the University of Washington in Seattle. “We always thought rods and cones were responsible for circadian rhythms and then we find there’s a particular cell that [sends signals] to the superchiasmatic nucleus, the brain’s central clock important for daily biological rhythms.”
As it turns out, melanopsin proteins are most sensitive to light in the wavelength range between 440 and 460 nanometers — in between indigo and blue. Many white LED designs create blue light centered at around 450 nm.

A 2005 study by chronobiologists in Basel, Switzerland showed that human volunteers exposed for two hours to 460 nm light at night experienced greater reductions in melatonin, a hormone regulated by the body’s circadian system, than when they were exposed to a roughly yellow-green light with a higher-wavelength of 550 nm. Melatonin, in addition to helping the body maintain a regular 24-hour rhythm of wakefulness and sleep, is an antioxidant compound that has been shown to protect biological molecules such as DNA.

So those LED bulbs are pumping out a great big peak right on top of the sensitivity peak of the eye for resetting the biological clock.

Well, I changed all the LED bulbs out for Incandescent bulbs (known to be blue deficient and no issues of UV leakage or what colors of phosphor are used) from my fairly large inventory.

Long story short: This morning I was informed that a long and restful deep sleep was the result. “First time in months”.

I also noticed less of an ‘edgy’ feeling this morning. Not a lot, just some.

We’ll be leaving the Incandescents in for a while before doing a ‘challenge’ or trial of the LEDs again. As one of them had been in the reading lamp next to the bed, and the spouse is fond of reading in bed, we’re hoping ( I’m hoping) that is the only one that is ‘an issue’. As I now have about $75 worth of LED bulbs, I’d like to use them somewhere… and with a 10 year or so life span, it will take a long time to use them up in the garage (where disappointing bulbs go to do penance…)

I’d use them for yard lights, but then the bunnies would be up all night too ;-)

So now I’m looking around trying to figure out what lights are used mostly during the daytime as candidates for the LED bulbs. Perhaps in the office… or over the in the Dining Room. (Then again, one late dinner and…)


Some links:

Outdoor-lighting research suggests strong LED impact in suppressing melatonin
13 Sep 2011

A multinational-research project on the impact of light pollution asserts that LEDs suppress melatonin levels to a far greater degree than high-pressure-sodium sources, potentially impacting human health.

It’s not the first time that the impact of white solid-state light (SSL) on human health has been questioned, but a new research project says that LEDs, for the same photopic flux output, increase “pollution in the scotopic and melatonin suppression bands” by five times relative to high-pressure-sodium (HPS) sources. The publication originating from institutions in Italy, Israel, and the US recommends regulatory limits for future SSL products.

The research entitled “Limiting the impact of light pollution on human health, environment, and stellar visibility” was published in the Journal of Environmental Management. The authors include Fabio Falchi of Italy’s Light Pollution Science and Technology Institute (ISTIL), Christopher Elvidge of the National Geophysical Data Center in Boulder, CO, David Keith of Marshall Design in Boulder, and Abraham Haim of Israel’s University of Haifa.

The research studied both LED and metal-halide (MH) sources relative to reference HPS sources. Both the LED and MH sources produce white light that includes more blue content at shorter wavelengths than do HPS sources that produce orange- to yellow-tinted light. Like much similar research, the new study apparently didn’t test actual subjects, but rather relied on prior research on melatonin-suppression levels relative to spectral content. The researchers came to the conclusion that MH lights suppress melatonin at a rate 3 times greater than HPS lights and LEDs suppress melatonin at 5 times the HPS rate.

The magnitude of the impact of melatonin suppression remains in debate. The secretion of melatonin has been shown as key in normal sleep/wake cycles and circadian rhythms. Some researchers also believe that it has “anti-oxidant and anti-cancerous” properties as the new research points out.

In depth technical look at designing LED driver circuits and some of the oddities of the little beasts. Nice chart of color vs nm.

A general look at lighting spectra and a graph showing the GE Daylight type CFL with a nice spike at about 460 nm too…

In Conclusion

If you are having any sleep disturbance issues, it is a good idea to look for some ‘less blue’ and ‘more yellow’ lighting alternatives to see if they make a difference for you. Probably also a good idea to make your laptop or iPad screen background color less blue as well. ( One article looked at iPad and laptop use and insomnia finding a connection with blue color).

Using “Daylight” type CFL bulbs is probably a bad idea in places you hang out late at night just prior to bed time. Using “white” LED bulbs is also likely to be an issue.

It doesn’t effect everyone the same way. I’m only marginally aware of it (but I’m a ‘night owl’ anyway) while the spouse had her sleep patterns all messed up.

We didn’t notice any issue using the old 2700 K ‘yellowish’ CFL bulbs or with incandescents. Only with the newer LED bulbs in a whiter color temperature. It might be that finding a 2700 K LED bulb could work (though with that spike, I doubt it. IIRC, the LED bulbs we’re using were supposed to be the incandescent color temperature range but might have been 3200 K. Still, not the “daylight” type at all. I’ll check the bulb a bit later and put up the specifics.)

I’m also very glad I had a buying binge and overbought Incandescent inventory. IFF it turns out that they are the best for undisturbed sleep, I’ve got enough for a lifetime. At least in the ‘evening’ parts of the house.

I continue to be amazed at the subtle things that cause our bodies to react and impact on our mental state. Even just the color of lighting used. Maybe aesthetics has more to recommend it than just what looks nice.

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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68 Responses to superchiasmatic LED light insomnia

  1. kakatoa says:

    Thanks for the heads up on LED lights. I don’t have any at our place. I guess I get to head to NV to stock up on a few more incandescent bulbs. Given a recent “Tip” over at WUWT about CFL’s I think I’ll skip buying any CFL’s for awhile.

  2. Power Grab says:

    This is news to me. Doesn’t having melatonin problems lead to mental problems. I wonder what kind of lights the Colorado shooter has been operating under?

  3. E.M.Smith says:


    Unmentioned in things like the Columbine shooting and Colorado is that often there is a history of “issues” and the shooters were on prescribed AHDH or similar drugs that are known to cause things like suicidal thoughts… It’s not the guns that’s the problem, it’s the drugged up (by prescription) kids.

    Melatonin is an important stuff in your metabolism (not just cognition but also things like cancer and similar antioxidant roles). Mess it up, bad things happen. But yes, we now can add “sleep deprivation from lighting issues” to the ways we are messing up our lives and bodies.


    I bought a “lifetime supply” mostly for the dimmer circuits where CFLs are sucky. Then found the LEDs looked nice and dimmed well. Figured I’d “way overbought” as LEDs were working in places where only Incandescent were acceptable before. Now I’m back to “about the right inventory”….

    As the spouse need some UV for the S.A.D. issue, it’s a bit of a feature (at low levels). Most of my CFL fixtures are metal anyway ( I like indirect lighting, so it is aimed at white walls and such mostly) with only a few being glass bowls (bath that’s an Incandescent on a dimmer) and Kitchen and table lamp / shades ( 2 in the living room and one in the bedroom. Of the three, 2 are incandescents on dimmers – one a 3-Way – and the other is a CFL but might go back to Incandescent now…)

    FWIW, you can buy 50 / 100 / 150 3-Way bulbs still and put them in a place (3-Way on low) that mostly runs the 50 W element. When that burns out, you have a 100 W bulb for regular fixtures… Also available are 100 / 200 / 300 and 50 / 150 / 200 and some others. I run one of these in the bedroom to “Manufacture” 100 W bulbs for the Bathroom…

    Use a dimmer and you can make an Incandescent last a decade or more. ( about 80% power). I have all my Incandescent bulbs on dimmers. I have a stock of 200 W “Utility” bulbs to be run on dimmers for 75 – 100 W worth of lumens for my “deep time” stash. Very inefficient but they will never run out when I reach that point… The 200 W are still available (as are “rough service” bulbs that are similarly long life and poor efficiency at lower temperatures…)

    Halogen bulbs do not like being run on dimmers. Some can take a little of it, such as those that are presently sold as high efficiency via being run really too hot – dim them some and they are in the longest life range. Dim them a lot and they do not reform the element. Halogen bulbs run hot so the halogen gas can scavenge the tungsten from inside the glass bulb and redeposit it on the element. So if you run them on dimmers, run them on high every so often for a while… and only dim them about 20% to 25%. (Or at the Very Dim end where not much tungsten is evaporating from the element anyway…)

    So really, we have just a couple of places where the CFL UV would be an issue. But we are not in those places long / much.

    Still, something to keep in mind… Don’t put them in reading lamps right next to your face…

  4. As usual Chiefio has come at a problem from an unexpected direction!

    On a more mundane level, I started buying compact fluorescents back in the 1990s when the only source was Amway. I liked them so much that by the time they were being pushed in every hardware store I had very few incandescents left.

    Dimmers don’t like fluorescents so I have a dozen incandescents still. As these fail they are being replaced by LEDs with a 7:1 energy saving.

    Frankly, the only reason I use fluorescents or LEDs is to save money. Anyone with 6th grade math skills should be able to figure out how much money one saves this way. That governments in the Republic of Ireland and California feel it is necessary to criminalise the sale of incandescents strikes me a shocking intrusion on individual liberty. Wasting money is one of the great pleasures in life. Next they will be criminalizing the sale of single malt scotch and fine cigars.

    The last time scotch was banned this country still repected its Constitution so the 18th Amendment was enacted. When the time comes for a national ban on incandescent lamps will our federal legislators have the decency to enact the 28th Amendment or will the head of the EPA simplify things by issuing an edict?

    I recently paid $20 each for 1W, 18 Volt LEDs from CREE (Raleigh, North Carolina). Pretty expensive for a lamp that puts out one tenth of the light that a 115V LED costing $10 can produce. No I am not completely crazy. Living in Florida one needs emergency lighting. The last time the lights went out for an extended period my flashlamp batteries ran down in a matter of hours. The Cree LED runs for 35 hours in my Sears Craftsman worklights. The standard 18V, 0.6A XRM bulb uses ~11 Watts compared to 1.3 for the LED replacement.

  5. Eric Fithian says:

    How about looking for a filter to notch out that 440-460 nm wavelength?
    Might make the light a trifle yellower, but….

  6. Petrossa says:

    Extremely interesting stuff. It’s a bit like the 50hz fluorescent light flicker in europe that caused people to get stressed. Makes the case for incandescent as still being the best option. I tried several LED lights, i haven’t found one the was ‘natural’. They are all off in some way, i guessed it was because the light frequency is too uniform. We are not used to uniform light, like music it needs harmonics. Remember the very first cd players. The sampler was so perfect the music was completely stripped of harmonics making it sound harsh.

  7. RACookPE1978 says:

    … Lettuce see how the testing goes. Sounds like a good solution
    Heck, sounds like a supersolution.

    In fact, a superchiasmatic-LED-insomnialicious solution.

    Didn’t Disney write song lyrics like that one time ???

    ( I too greatly prefer staying up late, going to sleep in the very early morning. And use blue screen savers and blue-tined sceen images as a backdrop.

  8. EM – looks like I’ll have to find some filter material to notch out that 460nm wavelength. I’ve been using low-energy bulbs for a long time, and once LEDs became available I’ve been changing to them instead. The recent LEDs (3W units) are rated as 3000K colour-temperature, which seems to be achieved by a yellowish top-filter on the SMD LEDs. Maybe these are notch-filters – I can’t find any spectral specs for the bulbs. I don’t find problems sleeping at night, but various significant others do, so it’s worth the experiment to find what difference a filter can make.

  9. philjourdan says:

    INteresting! I hate the CFLs, and fortunately can still get Incandescent. so have not moved to either the CFLs or LEDs yet. But I do like the LED light – which as you noted, appears more white than the CFL.

    I do not sleep through the night. I have not done so in over 10 years. So I am a lousy subject for testing. However, my wife does have problems. But before I do any experimenting on her, I will have her read your article and see if SHE wants to partake of it. If the Incandescent work better, I will be stocking up before the ban goes into effect nationwide.

  10. Charles Colenaty says:

    Excessive exposure to blue light (on a year after year basis, as with those who work out-of-doors) contributes to the development of macular degeneration. Special sunglasses are available that reduce the risk.

    Click to access draft%20update%20to%20blue%20light%20and%20AMD.pdf

    I was about to send the above off when my mind tugged at me question about LEDs and mouse research. It has been done and the results were scary for me. Two hours exposure per day for ONLY TWO WEEKS resulted in significant reduction in the photoreceptor layer of the eye! Let us hope that the mouse is much more sensitive to this stressor than humans. I didn’t have the time needed to track down a research citation, but I’m sure it is out there. This blog touches on highlights.—LED/show/1771077

  11. p.g.sharrow says:

    Time to ban all bans! ;-) pg

  12. adolfogiurfa says:

    @E.M. You are absolutely right. It is better a mix of several wavelengths, the closer to natural light the better, instead of LEDs which, by its nature, its emission is rather a very selected spectrum.
    This issue takes us to a wider subject: That of the undulatory nature of reality and the interactions between waves. Waves can be used to heal or to kill, so technicians cannot irresponsibly play with these without studying them beforehand. These laws, forgotten and anathematized by “consensus”, are well known by musicians. Haan: LOL!, trouble is that fungi and men breathe oxygen….so if it kills fungi it is very probable it kills us (if amount is enough- wattage-).
    Not a joke: This reveals the urgent necessity of replacing our current Physics paradigm to one based on the UNIFIED nature of reality, which btw has existed everywhere except in academia.

    @P.G. Specially those having a Kool-Aid taste…

  13. Power Grab says:

    FWIW, I want to mention that I sleep through the night when I take my dose of cod liver oil right before going to bed.

    I have minimal exposure to LEDs.

    I shun the CFLs at work and at home. When they installed the latest-and-greatest money-saving fluorescents at work, and I began having headaches and also discovered that the majority of our front-office staff had begun suffering stress-related symptoms, I switched them off in my office and brought in table lamps and incandescents. It’s not as bright in my office, but everyone who comes in comments on how restful and homey it is.

  14. jim2 says:

    Color TV’s can have a lot of blue also. Computer running lights are frequently blue these daze, blue is trendy. It’s all over the place! Anyway, when my SO can’t sleep, she hits the couch with the TV on, so I’m not sure WUWT.

  15. E.M.Smith says:


    Oddly, I was buying compact fluorescents before they had that name too… The old PL style with a socket adapter for lamps and an outboard magnetic ballast that you put in the power cord. Got them from Real Goods ( who mostly sold them to off the grid types and regular hippies… which gives an indication about my leanings ;-)

    By the time the political push for them had come along, I had most things that could take one already running high efficiency lighting. ( I was “Director of Facilities” in addition to Director of I.T. for a valley company for a couple of years. Developed an interest in all things lighting and even some sense of aesthetics… Was astounded one day to hear myself saying to our furniture vendor “I like the Jacquard Weave but do you have it in more of a periwinkle?”… )

    At any rate, I learned all the good points and the bad points of the various kinds of lighting long ago, and realized that incandescents had some places where they were just “worth it”. Politicians and Political Activists are emotion driven and lack any sense of depth in problem solving, so inevitably make bad decisions (as they are shallow decisions…)

    FWIW my solution to the same emergency lighting situation was to buy LED Maglight Flashlights. About the same cost as your LED bulb (at bulk discounters like Lowes and HomeDepot) and nicely portable. Make a nice club, too ;-) ( I particularly like the 4 cell “C” type as they are lighter and move faster.)

    @Eric Fithian:

    If you can find one, it would be a nice addition… but since the area under that chunk of the curve is a significant part of the total energy, your efficiency is going to have issues.

    IMHO the better solution is the UV LED and a cleaner phosphor mix OR use 3 LEDs in RBG with the blue a bit on the lower power side. (Though that gives three color spikes instead of a phosphor range, so some color rendering will be a bit off… while the eye will see the light as ‘white’ individual colors will reflect the three peaks a bit differently than a smooth spectrum, so some colors shift and the CRI Color Rendering Index goes a bit lower).


    I’m one of those folks who can see flicker in lights at a little faster rate than most folks. In the old TV’s I could see some of the ‘squirm’ and from even 60 Hz tube (magnetic ballast) bulbs I notice the flicker. 50 Hz would drive me nuts… The Electronic Ballast with 10 kHz type ranges make the CFL useful in a lot of places where I just could not stand them before. Phosphor persistence matters… one of the minor problems with the LED RBG approach. No phosphor means no phosphor persistence means you flicker at the rate of the power supply to the LED. Don’t know what that will do at higher frequencies. BTW, different species have different max flicker rate perceptions, so what is OK to you may be a strobe light to your pets…

    Had an old wooden cabinet radio with a giant speaker in it (tube driven…) that I just loved. Digital never could come close. Why? The cabinet was designed by folks who made musical instruments. Not a faithful reproduction of the signal, but with rich wood tones… Seemed to make everything sound better. Plastic never could come close.


    Might be faster just to put a CFL or IC bulb in the bedroom and other ‘just prior to bed’ area and see what happens.

    @R. de Haan:

    Oh Dear! Keep it away from the bread making and brewing areas!!

    But it looks like maybe I can put them in the refrigerator to good effect!


    Last time I was at a Home Depot they had Philips Incandescent bulbs in dozen packs for something like 19 cents / bulb ( Florida). It was abit under $3 IIRC. ( I have several in my stash…) It might be cheapest and easiest to just go buy a box and try them. Worst case, you have some “trade goods” for after the ban… ( I expect them to go for about $2 to $4 each to desperate folks who really want them…)

    @P.G.: I agree!


    Oddly, recent advances in biology have indicated a closer relationship of fungi to animals than to plants… so you might be on to something there…


    Part of why my lighting plan has an incandescent in almost every room with a CFL. Choice.

    Exceptions are the kitchen (only one bulb – but an IC ‘night light’ plugged in), the Garage (temporary occupancy…), and the kids room (who wants to listen to Dad drone on about light bulbs…).

    In the living room, the table lamps are ‘mixed’ and the pole lamp is too. So you can set the mood as comfortable OR make it ‘cleaning time bright’… Bedroom has 2 (IC on dimmers for longer life and more mood choices, HIgh Efficiency lighting for those cleaning and working moments… or as ‘nobody home’ fill lighting.

    I can just FEEL when an fluorescent bulb is on. But the high frequency electronic ballasts have helped. Using them in mixed sets makes it “OK”, but not great. That was why I was converting to LEDs in selected fixtures. To deprecate the CFLs and replace some IC on dimmers (where I didn’t want the reddening of the light at low settings). Now that’s all out the window for a while as I do a bit of a re-think…

    The Garage recently got new bulbs ( I had some old Circline 8 or 9 inch screw in ballast that had been left ’empty’ where their bulbs died a decade or so back – since the ‘new’ curly bulbs on subsidy where cheaper than the replacement bulbs. That have a nice plastic cover on them too. I decided to put them back in service in the garage just a month ago or so.) Looks nicer than the naked curly bulbs… ) so not a lot of need in the Garage…

    Not sure what I’m going to do now in the ‘remix’…


    New meaning to “blue screen blues”? ;-)


    Spouse reports today was not as deep a sleep as the first night, but still better than prior times. I’m not all that surprise as a first ‘deep sleep’ after being sleep deprived is usually followed by a less deep one on the rebound.

    That “2 in a row” have been significantly (nearly dramatically) better is the start of a trend…

    I think this issue “has legs”.

  16. Jason Calley says:

    @ Power Grab “I sleep through the night when I take my dose of cod liver oil right before going to bed.”

    Cod liver oil is the traditional source of D3. I have for the last few months been doing some home experiments with vitamin D3. I find that if I take about 8,000 or 10,000 units before going to bed, my dreams are more lucid, more coherent and more memorable. Note that there are mixed ideas on how high a dosage is toxic. Some sources say toxicity occurs with prolonged intake of 4,000 units a day, others say as much as 40,000 units or more. Anyway, point is, vitamin D3 seems, (at least to me) to influence sleep and dreaming. Experiment if you wish, but be aware that prolonged high dosages may be a problem.

  17. Petrossa says:

    On lights. I stick with halogen and triacs. I leave the damper coil out now that all modern equipment isn’t bothered by the feedback, so no audible noise.
    You can adjust the color by taking 50 to 100 w lamps and turning them way down. Goes from a warm sunset glow all the way to bright white. I can’t think of a lightsource that is that versatile at that low cost at that long a lifetime. I had my first burnout only recently after 9 years of faithful service.

    CFL makes my head spin, the new cfl’s run at 120 hz and give me nausea. And the awful colors, yuck. Makes everyone look like the living dead.

    Good LED’s cost a fortune and aren’t half that long lasting as they claim. Affordable ones for sale here come from that famous place China, known for it’s barely substandard quality. They consume as much energy on as off.

  18. @Jason Calley,
    I don’t know how cod liver oil got into this thread but since you raise the subject here goes.

    My mum (British for “mom”) used to dispense “Scott’s Cod Liver Oil” daily by the teaspoon. Of course I hated it and vowed never to touch that vile stuff once I broke free of her maternal influence.

    Twenty years ago arthritis struck. I would have been forced to give up playing golf but for fish oil. Since then I have consumed a minimum of 4 grams per day. One benefit is that I can drive the ball 280 yards off the tee at age 75, much to the consternation of the old farts I play with. Unfortunately my short game sucks so my handicap is 21.

  19. Llanfar says:

    The Ott lamp comes awful close to the identified spectra – 435.8nm (ref. .) And my wife knits under one evenings…nights…into morning frequently. I don’t know if that is in the grey zone, but it’s worth experimenting on her.

  20. Petrossa says:

    Even further OT, i was given codliver oil in capsules which i always bit because i liked the taste so much.

  21. Pascvaks says:

    Is anyone else getting the impression that the folks at UL aren’t doing as many tests, or taking all the time, as they should on all the new gizmo? This sounds like a job for our Super Heros: EPA Man, HHS Girl, CDC Woman, and DOE Boy! (Oh well, it might sell a few more comic books;-)

    PS: Think, maybe, the suicide rate isn’t all self-inflicted and there’s more murder than we realized in the National Stats?

  22. adolfogiurfa says:

    So…..Blue light vs.codliver oil, why not Melatonin?

  23. E.M.Smith says:

    @GallopingCamel & Petrossa:

    Well… we have a pattern / trend… MY English Mum fed Cod Liver Oil to me when I was ill and gave me cod liver pills as a vitamin ( and I liked the flavor of the pills rather a lot and bit them too ;–)


    The UL just tests that things don’t start fires or electrocute you. (That is, the UNDERWRITERS of insurance policies are not taking too much risk…) So the UNDERWRITERS Lab tests for what insurance underwriters insure. They don’t insure quality of sleep…


    The spouse took melatonin. Sometimes helped a bit, often not. The problem is that the body makes its own, and if you down regulate the normal level then add a bit, you still end up below desired levels. So you are in a race condition between the added in pills and the lowered by blue light. Better just to leave the race…

  24. adolfogiurfa says:

    The main Sun´s wavelength is that which corresponds to the wavelength of Calcium (found in Sun´s chromosphere) so that cod liver oil (Vit D3) lacks its complement Calcium.
    BTW, as our Sun is having troubles:
    In WUWT article we find M.Vukcevic´s opinion:
    Making reference to:
    Many people is having troubles with orientation, equilibrium (dizziness). In special women. Why? because women have less hemoglobin, less iron than men (due to menstruation) and have no presence of magnetite in face bones.
    …..interesting times, indeed!

  25. E.M.Smith says:


    Interesting link on that light. I love “kitchen science” and that looks like something you could do at home ;-)

    @Charles Colenaty:

    Oh Dear! From that link, pretty strong stuff:

    Over the past two years there have been a number of studies investigating the mechanisms
    involved in the development of Age-related Macular Degeneration (AMD). The results of these
    studies have consistently supported the premise that blue light exposure raises the level of
    oxidative stress in retinal cells and promotes the development of AMD. The European Eye Study
    (EUREYE) has now confirmed that blue light exposure combined with low levels of serum
    antioxidants is associated with the formation of AMD.(1a)
    The results of this new research on the pathogenesis of AMD provides compelling evidence that
    increased exposure to blue light over a lifetime will advance the onset of AMD, and increase the
    likelihood of blindness later in life. This has lead some prominent researchers on the
    mechanisms involved in the development of AMD to now assert that “It is photo-oxidative
    stress, or the cumulative exposure to free radicals from blue light over a lifetime that causes

    That mouse study also would point toward avoiding blue CFL ( “Daylight” or 5000 K type) bulbs as well.


    I have a DVD recorder in the bedroom that has a modestly bright BLUE running LED. I have to keep it powered off if I’m trying to sleep. Had always just thought it was too bright; but now I’m thinking maybe there’s more to it…

    I’ve changed my background wallpaper on the laptop to black, but it still has a couple of ‘blue/white’ status LEDs on the edges. (Disk activity, power on, network connected, and battery charged). Enough to be an annoyance in a dark room while someone else is trying to sleep.

    I’m going to be shopping for more things with red and green LEDs for status lights and less blue…

  26. jim says:

    Another interesting characteristic of blue light is that it has a high enough energy to knock electrons right out of your retina’s ball park. It can contribute to macular degeneration. It can cause some materials to fluoresce in the (lower) visible wavelengths.

  27. philjourdan says:

    @gallopingcamel says: 24 July 2012 at 3:55 am

    Old farts? WHo do you play with? Centigenarians?

  28. Larry Geiger says:

    My clock has a blue light. LED I suppose. It’s VERY bright. Like a bright night light. However, I can read it at night. I can’t read a red clock. My eye doctor says it has to do with the wavelengths that my old eyes can see well. My wife sleeps right next to this clock. Hmmmmmmmmmmm. She is developing macular degeneration (thought probably age related), but still I think that we might look around for a new alarm clock. Maybe amber?

  29. w.w.wygart says:


    You can try using color filters on your existing LED lamps if you can tolerarte losing a fair amount of brightness. The old gaffer/lighting tech side of my brain informs me that Lee Filters now produces a line of filters especially for LEDs that might be helpful.

    I haven’t used LED’s in that capcity since I am a bit of a neanderthal and am most familiar with tungsten, HDMI, and fluorescents, but you can give the folks at Lee a tootle, or call your nearest theatrical supply or rental house for more info.


  30. w.w.wygart says:

    Ah. even better, looking a little further down the page I see that Lee has a series of four LED conversion filters.
    622 – converts white LED of 7000K to 3200K [tungsten]
    624 – converts white LED of 6200K to 3200K [tungsten]
    626 – converts white LED of 5550K to 3200K [tungsten]
    628 – converts white LED of 5000K to 3200K [tungsten]


  31. Pascvaks says:

    EM – “UNDERWRITERS Lab tests for what insurance underwriters insure. They don’t insure quality of sleep…”

    Hummmmmm… bet the boys at UL will soon be worrying about the quality of sleep and retinas soon, something tells me a few thousand lawyers are taking depositions and drawing up formal complaints as we speak. Wonder how they found out?;-)

  32. Petrossa says:

    Nowadays its fashion to put blue leds in just about everything. The first thing i always do is screw them open and replace the blue with another colour. For some reason blue leds really shine intens eand are very irritating. You just always see them. The other i bought an eight channel HDMI switcher. All blue indicators. Pity about the garantuee but that is just insufferable.

  33. Judy F. says:

    I am not a doctor, nor do I play one on TV… It is very possible that your spouse is reacting to some lighting issues. I have no way of knowing. But you indicated on a posting several months ago, IIRC, that you had children and friends of children in and out of your house. Then the other day, you said that your son had moved out of state to build a church. This comment is just from personal experience, but there might be some “empty nest” issues going on as well. I did the dance of joy when my daughter left for college several years ago, thinking that I was finally going to get some peace and quiet. It got too peaceful and too quiet in a big fat hurry. I found myself watching TV late into the night and not sleeping well when I finally did get to bed. It wasn’t what I would call depression, it was just a new stage in my life that took some getting used to.

    I don’t know your wife’s situation, but it could be that there are several things going on at the same time that are making sleep difficult. Just a view from the feminine side.

  34. adolfogiurfa says:

    @Judy F It is interesting a female´s point of view. Guess you are right.

  35. E.M.Smith says:

    @Judy F.:

    The Son that went off to build a church did so from Los Angeles. He has been ‘out of the nest’ for 4 years of college and a couple of years of a job post college.

    The “kids” coming and going are my Daughter who is “20 something” and her friend. Been going on for a few years now about the same.

    Reasonable things to highlight given the data you had available, but not things that have changed in the last few years (added data) so not likely issues. We’ve also gone through ‘end of school year’ and ‘summer off’ for a dozen years now without this happening.

    That things improved a lot on changing the lights back gives a pretty good confirmation. (We need to do a swap to LED again trial to confirm, but right now SWIMBO is not interested in my experiments ;-)


    Also a good idea… but a filter and housing is likely to cost more than the bulb ( $10 ). I’m happy just to put in a different bulb from my inventory (as I have a lot right now) and hopefully over time the LED makers will realize this is an issue and “fix” it. ( i.e. maybe I can toss $15 – $20 / bulb at new LED bulbs that are not ‘blue rich’… while these bulbs either stay in inventory or go to “blue OK” uses. Yard lights after the bunnies are gone ( not planning to raise bunnies for the next 20 years too ;-) or garage lights or porch light or…

    Yes, I have a decade scale time granularity to my lighting inventory ;-) (Forced into it by the Bulb Ban, but “It is what it is. -Paul The Czech / Swiss Mechanic”.)

    @Larry Geiger:

    I’m happy with a white faced unlit clock and a bedside light… but what do I know ;-)

    I think there are also GREEN glowing clocks out there too. Typically green-yellow is the color more readily seen by folks.

    BTW, on the Macular Degeneration: Found several pages saying UV and Blue light cause and / or aggravate it. One recommends glasses with a specific filtering in them. IIRC it was a specific cut off at 400 nm. It does look like cutting out blue light makes a difference in prognosis.

    Researchers have identified melanin as the substance in the skin, hair and eyes that absorbs harmful UV and blue light. It is the body’s natural sunscreen protection. Higher amounts of melanin afford greater protection against damaging light rays, but melanin is lost as we age. By age 65, about half of the protection is gone so that we are more susceptible to eye disease such as macular degeneration. The Schepens Eye Institute reports that “the blue rays of the spectrum seem to accelerate AMD more than other rays of the spectrum.” Very bright lights such as sunlight or its reflection in the ocean or desert may worsen macular degeneration. The Institute recommends that sunglasses protect against both blue/violet and UV light.
    Misleading claims about certain glasses providing UV protection can be easily confusing to consumers. A pair of glasses might be labeled UV-absorbent, for example, but the label might not indicate exactly how much UVA and UVB rays are blocked. Sunglasses should be labeled UV 400. It is recommended that you protect yourself from UV radiation up to 400 nanometers, which extends into part of the visible spectrum to ensure complete blockage of ultraviolet light. This is what distinguishes “cheap” sunglasses from more expensive ones.(1.)

    So looks to me like folks with Macular Degeneration need to be looking at the world through rose colored glasses ;-)

    These folks are a bit more ambiguous (but also fail to mention sun sensitizing drugs like tetracycline as potential enhancers of sun damage to eyes):

    In many primate studies, blue light has been shown to cause a photochemical reaction that produces free radicals in the RPE and the rods and cones. Researchers believe that these free radicals interact with the high oxygen and lipid content in human rod and cone tips to produce abnormal chunks of metabolized waste that cannot be properly processed by the RPE, clogging up the macula’s maintenance system and producing dry macular degeneration.

    Melanin, the substance that gives eyes their color, protects the macula by trapping light rays so they don’t reach the macula and cause damage. People with fair skin and blue or light-colored eyes may be particularly susceptible to macular damage by blue light because they have less melanin in their irises. Their blue eyes transmit up to one hundred times as much light to the back of the eye as dark colored eyes do. Additionally, when the light reaches the choroid and RPE of people with fair skin and blue eyes, there is less melanin there to absorb the radiant energy, leaving these tissues more vulnerable to light damage. Can blue light rays cause macular degeneration? Can you reduce your risk by protecting your eyes from blue light? The answer is maybe.

    Although the laboratory studies on animals seem nearly unanimous, the real world studies on people have produced conflicting results. Some studies positively link macular degeneration with any kind of light exposure, other studies have found a weak correlation between macular degeneration and blue light exposure, and yet a third group of studies has found no correlation at all between macular degeneration and sunlight. One Australian study concluded that the problem is not total sun exposure, but exactly how sensitive you are to the sun. It hypothesized that people who have plenty of melanin and don’t tend to burn easily are at less risk for macular degeneration than people who burn easily or are bothered by by sun glare. This study also concluded that people with blue irises are at increased risk for ARMD. These results, which have not been replicated or confirmed, do not allow me to state absolutely that blue light contributes to the development of macular degeneration, but it is certainly plausible. Based on the possible benefit, I recommend wearing blue blockers, especially if you have fair skin and blue or light-colored eyes, if you have any other risk factors, or if you spend lots of time in bright sunlight, or on water, sand, or snow, which reflects sunlight. Alternatively, wear a sun visor when you are outside.
    Blue Light and Blue Blockers

    Unlike UV light, blue light is visible to us. Blue light waves are what makes the sky, or any object, appear blue. Blue light waves are also very short and scatter easily, so a great deal of the glare we experience from sunlight also comes from blue light. Since we can’t see UV light, we also can’t see the lens filter used to protect us from UV rays. Conversely, since we can see blue light, we can also see blue blockers, the lens filters that block blue rays. Blue blockers do not act like regular sunglasses. They appear tinted, but they do not reduce overall light or make the world look darker. They alter the appearance of blue and green colors and reduce glare, but they don’t affect the way other colors appear. In fact, they may even improve color contrast. Because of these characteristics, blue blockers were very popular a few years ago as sports glasses. Many people with macular degeneration find them particularly helpful regardless of their health benefits, because they reduce glare indoors and outdoors while keeping the world bright and visible.

    At any rate, as I already hide from the sun a lot of the time I’m not too worried about my blue eyes or redhead gene impact on the eyes… but I might start wearing cool shades anyway ;-)

    More here:

    This link explores “light therapy” for S.A.D. using a similar blue peak ‘light box’ instead of a full on UV lamp and finds it effective; but then also explores the issue of light and other problems as well. It may be that we just need to use the LED bulbs in the first half of the day (so the biological clock stays right and the S.A.D. gets a treatment…) while swapping to yellower later in the day. (Which would be nice and would let us dump the UV 20 minute morning treatments…)

    Golly, that light stuff is complicated… Maybe I’ll just put in some large sky lights and be done with it ;-)


    After the DVD writer experience, I now look at anything going into the house and if it has bright blue LED status lights on it, don’t buy it. Sadly, my Mercedes has a bright blue High Beam notification light (which seems really dumb to me… just when you need to see in the dark the most, dump a color of light at your eyes that cuts down on night vision…) but I just put black tape over it for long drives (and don’t use high beams most of the time…)

  36. adolfogiurfa says:

    @E.M. What about your savings in old fashion light bulbs you recommended us time ago? I thought you had bought some…

  37. EM – as a result of this post I’ve set the blue of my monitor way down. I’ve been using the computer a lot recently and was noticing some eye-tiredness. The new settings do seem to help, and I’m not noticing major problems with colour-rendering – just a bit more like reading an older slightly yellowed paperback book.

    It’s no way a scientific test, but on a personal level it’s worth trying.

  38. E.M.Smith says:


    Um, I’ve said a few times that I have “a lifetime supply” of incandescent bulbs. No problem there. I’m just trying to get the optimal solution of that light quality (or close enough) with the minimum consumption of electricity (and my incandescent bulb stash…)

    So I could easily make the whole house incandescent bulbs now (and for about 20 years) but where’s the fun in that? ;-)

    Just converted the hall entry way to a dimmable CFL. We’ll see how well it works or it’s going to an incandescent bulb…

  39. Judy F. says:


    Glad to hear that it is most likely a light issue with your spouse. It is so much easier to change a lightbulb than work through the other issues. :)

  40. Petrossa says:

    The leds that i couldn’t replace due to wife getting anxious about warranty i made black using an alcohol based felt tip marker. The blue just shines through enough to see something is there. Maybe an idea for your Merc.

  41. philjourdan says:

    @Simon Derricutt says: 26 July 2012 at 10:34 pm

    I am not sure if you are being sarcastic or serious. However, I have a nice big 27″ monitor that doubles as a Video Codec. It was free (so no one to complain to), but it has always been reddish in tint (and I have fiddled with the controls to no avail). However, while my video conference participants look ruddy, and my blues are more purple, it has not really been a problem to use. So perhaps K-Mart was wrong. Blue light is not special.

  42. Phil – definitely serious. I assume that monitor is a CRT, and if so try a demagnetiser on the visible surface. It helps if you use a real tape demagnetiser and gradually move it further away from the screen whilst waving it around. Colour-bias on a CRT is often the shadow-mask becoming slightly magnetised, and degaussing it puts things right again. The other reason for the blue being low is a gun/driver problem, and you’d need the schematics/workshop manual to fix that.

    The new colour tint on the monitor is a lot easier on the eyes. It’s almost certain this one is lit by CCF tubes rather than LEDs but those still have a blue/UV component.

  43. philjourdan says:

    Simon – nope, it is an LCD. I found out about degauzing CRTs back in the 90s (when a company installing computers at a school trucked them by a transformer).

    Like I said, it is an inconvenience, but hey! I GOT A 27″ Monitor! And it was free (the company was trying to sell us a bunch of them – they did), so I cannot complain.

  44. E.M.Smith says:

    Today the CFL went a bit “squirmy”. At middle and even nearly full power it had occasional surge / flicker. Took it down to low power and it was “OK” but not completely smooth. So about 24 hours of operation and it’s “dodgy”. OK, took it out. It was “way hot” to the touch in the ballast and smelled of cooking phenolic electronic parts. It was working when removed, but after cooling an hour, it would no longer work.

    The hallway light is now a 52 W incandescent that is normally run at about 25 W … but at full power is about right for sunny days (entry from bright light to dark house) and cleaning the area…

    I’ll be trying another of that particular kind of CFL on a different dimmer and someday will perhaps buy one of the $15 ‘dimmable’ CFLs from another maker. Some time after the bulb has “rested” and I do some more “experiments” on it, I’ll post the details of the bulb, dimmer, and all. For now I have a “No Go” on CFLs in the only LED/CFL approved-advertized-offered wall mount dimmer at the local hardware stores…

    And folks wonder why I’m not fond of a ‘Bulb Ban’… How about “Because they don’t work in about 1/2 of the total applications I have.” (I’m fond of dimmers and variable lighting intensity…)

    So for now, all my dimmers are back to Incandescent only and I’m back in the “search for a reliable dimmable CFL” and / or “search for a non-blue LED” bulb realm.

    One bit of good news out of all this: Now I’m feeling pretty good about those 32 (2 boxes) of 57 Watt bulbs I bought on an impulse ;-) (They were something like $2.90 / 16 pack so it wasn’t a cost thing, but I have to store them…) I’d been kind of regretting not making them 100 Watt bulbs and just use more dimming; but a 100 W run at 25 W is way red… while the 50 ish run at 25 W is nice. So it’s a ‘feature’ more now ;-) Besides, I already had a few boxes of 100 Watters…

    Ah well, I’m sure that the economy had no better use for me than coping with the side effects of stupid decision by the central planning aristocracy… /sarcoff>;

  45. Chiefio said:
    “So for now, all my dimmers are back to Incandescent only and I’m back in the “search for a reliable dimmable CFL” and / or “search for a non-blue LED” bulb realm.”

    I have an array of 6 lamps on a dimmer so the total load is 360W max. I replaced one of these lamps with a EVERLIGHT Series SL-60B made in Taiwan. This lamp produces light that is slightly whiter than my incandescents at full power. Depending which spec you read the maximum consuption is 8W or 12W.

    This LED produces a pleasant white light, dims very nicely although it does not match its incandescent colleagues which change color dramatically as they dim. The dimmer works happily with no strange smells and this is what you would expect as the load diminishes each time a LED replaces an incandescent.

    I had some concern that the dimmer might fail with really low loads. With a single 60W incandescent it works just as it does with a 360W load. With a single LED the dimming still works but the control setting is more sensitive. I expect that with 6 LEDs the dimmer will perform normally.

  46. p.g.sharrow says:

    One nice thing about being a central planning aristocrat is you can not be held responsible for the outcome of your actions. Em, sounds like the legal definition of mental incompetence.. pg

  47. Petrossa says:

    Due to the simplicity of constructing a incandescent dimmer, the ridiculously low cost of the parts (2 condensators, a diac, a triac and a potentiometer), the low cost of halogen/incandescent, the energy saved when dimming an incandescent, the lifetime extension, the perfect colour range one can obtain it beats any solution out there.

    I have also a couple of voltage driven dimmers connected to an USB port so my computer regulates the light intensity according to surrounding light.

    Personally i see no reason

  48. Petrossa says:

    to change for another system

  49. jim says:

    Hey Gall. Camel @ 28 July 2012 at 4:28 am
    Probably the best way to hook up LEDs to an AC dimmer is to configure them as as parallel, but opposite polarity; or as a full wave bridge. This will move the frequency of on/off from 60 to 120 cycles – should be easier on the eyes if you detect that 60 cycle flicker. I haven’t looked into the commercial configurations – some or all may already be doing this.

  50. For those with sensitivity to flicker, there are various chips made for car lighting that take a 12V nominal (i.e. up to 16V with transients to 40V) input and will drive a string of LEDs in constant-current mode. There’s going to be a slight ripple, but at quite a high frequency. Since the drive current is normally set by a resistor, this will also act as a dimmer. This sort of circuit is a bit more expensive than the simple diac+triac+cap+resistor setup, but the chip costs are going down as the quantities manufactured go up. It’s also looking like OLEDs may be getting close to being available to normal people and with reasonable cost and longevity (>2000 hours). If people want to do this sort of thing I’ll go hunt the sources and check costings.

  51. G. Combs says:

    Thank you for this post. As a female with sleep problems who loves to read in bed, we will try going back to incandescents too.

  52. jim says: 28 July 2012 at 2:40 pm

    “Probably the best way to hook up LEDs to an AC dimmer is to configure them as as parallel, but opposite polarity; or as a full wave bridge.”

    That makes sense so I tried to find out whether the the SL-60 is full wave or half wave. I could not find anything on the Internet so I tried to test my SL-60 with a DC source. The highest DC voltage available was 36 Volts which failed to light the lamp in either polarity.

    I connected the lamp to my trusty Kill A Watt and here are the readings:
    Volts = 122, Amps = 0.05, Power = 6W

    From my understanding of how the Kill A Watt works I believe this shows that the SL-60B is operating full wave. I was a little surprised to find the power consumption was lower than the specified 8W.

    When I retired there was a drastic downsizing. My 70 year old, 12′ x 6′, 2,600 pound, snooker table was sold along with my lab equipment (‘scopes, power supplies, components etc). Even so it won’t take much ingenuity to settle the question you raise. I plan to buy another SL-60 to find out what happens if one runs them in series.

  53. Gallopingcamel – I couldn’t find specs for the SL-60B, but the SL-60A has a voltage input 100-240VAC. It thus probably has a switch-mode power supply inside it, and almost certainly full-wave rectification before the rest of the circuitry. Running the lamps in series (thus at half-voltage 55VAC) may just cause the driver FETs to blow through taking too much current, but they may have been clever and put an undervoltage lock-out in so they just won’t light, instead.
    Correction, just found some data on SL-60B at and it should be 11W, still 110/220VAC.

    A lot of SMPS AC designs will happily work on DC of sufficient voltage. Raise the voltage to around 100VDC and the bulb ought to work correctly – just a bit nasty if you touch the wrong bit.

  54. Petrossa says:

    Why go through all that trouble? I have a couple of 800w computer PSU’s with its own wiring through the house. Drives everything, including any LED’s, 12v no longer cordless drills due to conked out batteries, my toothbrush, various electronic devices, my bathroom 300w car stereo, my folding stairs hoist etc.

  55. E.M.Smith says:


    I started a 12 VDC power system in the house back during the rolling blackout of the Governor Gray (out) Davis years. I got part of the garage wired, then the whole thing went on hold when we got reliable power back (after swapping out the PC Democrat for a non-PC RHINO who we thought could stand up to the opposition but instead folded his cards and retired on the job at the first resistance… but after fixing the power issues.)

    At any rate, I’ve got some old car headlights in the garage wired and switched and even had a 12 VDC power source via a battery charger / old-battery. The battery later expired ( it was already marginal then) and the system is deprecated, but still in place. As we’re headed for $1/4 / k-Whr power now, and $1/2 k-Whr “soon”, it’s likely time to finish the build out. (New battery in the battery box, put the charger back on it. Re-check everything.) Wire in the inverter to make 110 VAC ( a 2 kW job on the shelf) and add some charger cables to clip onto the car ( and / or use the Honda generator) and I’m pretty much “good to go”.

    The old car headlights were an ‘expedient re-use’ of bulbs that had the ‘dim’ filament burned out. Not very efficient, but cheap light over a rarely used workbench and with good color rendition (important when reloading and wanting to know color codes are correct… or that all colors of ink are visible in the notes and directions…) Now I’d likely replace them with a HID headlight from a wrecker if I was starting over or “white” LEDs from cars if available. ( Backup lights? )

    Then again, it is likely the case that white LEDs are a lot more available now as parts… so maybe building my own… ( Wonder if the RV outlets have 12 VDC LED bulbs…)

    First thing to pop up on a search says “yes”:

    Hmmm… Maybe that 12 VDC system would be a nice winter project…

    Probably won’t wire the whole house though. Easier to just swap some of it over to the inverter… Yard and garage first anyway.

    The old PC power supplies as 12 VDC is an interesting idea… Lots of those around, fairly efficient and clean power output.

    @G. Combs:

    Let us know if it helps. For the spouse, it’s been about a 50% improvement. ( About 2 x as many ‘normal sleep’ nights and even when getting to sleep late, sleeps better.) We’re still tracking down other influences ( like keeping curtains pulled as the morning sun comes in the large window instead of letting it reset the biological clock to ‘morning’ in the morning…)


    Sounds about right ;-)


    I suspect I may end up in the “build your own LED bulb” business if I want a clean low-blue white color mix. Probably try some more of the commercial bits first, though. Would be nice to find someone with a commercial product that didn’t hit the “blue sensor” in the eyes. If none are out there, it is an opportunity… Perhaps using UV LEDs, a better phosphor mix, and a UV filter… I know I’d pay extra for it. So that usually means I’d be willing to make my own if I can’t buy it.


    Due to the peculiar way LEDs have resistance change with voltage, they pretty much need some kind of current control on them anyway. Might as well just make it an adjustable “constant current” source and run them on DC. ( Full wave bridge rectifier costing nearly nothing these days). Doing a direct feed of AC into LEDs is just asking for trouble. (See the link above at gizmology). Yeah, you can do it, but…


    Generally, so far, the Incandescent swap back has worked fairly well. We’ve started a slow reversion toward more efficient lights in some places to see what happens. A bluish LED in the living room that’s mostly for morning / mid-day use. A CFL with a decent 2700 K color temp into the reading lamp. (Sorting out if it is Incandescent vs ANY or just incandescent vs LED. So far it looks like only the LEDs. But the testing has to be controlled to know for sure.)

    (There is a small risk that some CFLs could have an excess blue spike that isn’t obvious, so it could vary by individual bulb. I need to look up the mercury emission lines and try to find color spectra on the brands of bulbs and… So it will be a slow project. One bulb at a time. As needed. For now, it’s just the IKEA 11 W bulb in the reading lamp… )

    The bottom line is pretty simple, really. It matters to manage your “biological clock” reset times via blue light awareness. Something we didn’t need to do in the era of Incandescent bulbs and old glass tube TVs, but something we need to do in a world full of HID bulbs, LED bulbs, LED TVs, LED computer screens, etc.

  56. Petrossa says:

    My fantastic wiring with PSU to drive the bathroom accessories

  57. Chiefio said:
    “As we’re headed for $1/4 / k-Whr power now, and $1/2 k-Whr “soon”………

    This is why I love California!

    You try every dumb idea that will push up the cost of electric power so the rest of us won’t have to. Thank you California!

  58. P.G. Sharrow says:

    This is a electronics supplier that has quite a web connection for information on LEDs:
    I would think that the ChiefIO would know of them as they are local to him. pg

  59. adolfogiurfa says:

    @gallopingcamel: Don´t you think it is a kind of disguised “evacuation” procedure? The more people leaves Kaly-pornia the more will be saved from the Big-One.

  60. jim2 says:

    EM – You could get some diffraction grating and look at the bulbs through it and a slit.

    755227 Diffraction Grating Film $16.95

    In Stock

    Could probably find it cheaper yet.

  61. E.M.Smith says:


    My wife would shoot me ;-)

    ( I have coax going through exterior walls in 1/2 inch PVC pipe conduits already for a minor antenna farm I have used for SWL from time to time ;-) Yes, I could likely add exterior 12 VDC wiring to it, but the distance would cause the IR losses to be more than just doing the inverter to 110 AC …Though I have thought of making a 400 Hz inverter to make the inductors smaller and then turning it back to DC at the other end of the link ;-)


    You are most welcome. I’m glad to know our blood letting will not be in vain …


    Nope, didn’t know them. It’s been a long time since I bought lots of new parts. Mostly now I’m just reusing old ones ;-)


    Not enough are leaving… We’ve had some significant wealth flight, but enough Mexicans have come in to stay at just a minor net population loss. Then again, many of them do not show up on the official statistics… ( When I was a kid, my best friend always had a few ‘cousins’ around. One day a “cousin” came in talking about “La Trucke Verde!” and everyone headed out the back… As I went to join them I was admonished by Mama Celerina that I didn’t have any reason to worry about the INS. It was the first time I felt “different” in Miguel’s home… But at any rate, I’ve been comfortable with illegal aliens for about 1/2 century now… so my pointing out that they exist isn’t a pejorative. Just more “cousins” hanging around…)

    So no, not a population strategy. Just plain old garden variety greed, graft, rent-seeking, and stupidity in government.

  62. E.M.Smith says:

    Oh, and we’ve gone to using some of the bluer lights early in the day ( so morning through about 2 pm) as a way of directly telling the biological clock “It IS daytime NOW!” and the insomnia is even less. (Near none now).

    Looks like “managing the clock” on both ends is helpful. Both NOT resetting it late at night and deliberately using blue to reset it early in the day (if not going outside to just let the sun do it ;-)

    So we’ve got one of the LEDs back ‘in pay’ in the living room / morning activities area. Converting the bedroom reading light back to CFL did not cause any issues either.

    So looks like CFL / Incandescents in night areas or for night use; and the LEDs only for “daytime ambiance adjustment”…

  63. Jim2 – I’d use an unrecorded CD or DVD as a pretty reasonable diffraction grating. There’s a problem with the concentricity, but it is something we all tend to have at hand.

    pg – I use Future Electronics. They used to supply us at Xerox, and were definitely one of the best then. They even supply things in units of 1 for a lot of things, at not too much of a cost increase, and have a lot of data available about the stuff they supply. They stock around 200K items, of which around half seem to be in-stock at any time, but industrial lead-times apply if it’s out of stock. Delivery (when in stock) is quick and not expensive. It could be worth your while looking and comparing costs.

  64. jim2 says:

    Simon – I use Mouser Electronics. They are happy to sell in small lots. I’ll check out Future Electronics. We also have a Fry’s here.

  65. Petrossa says:

    My wife did shoot me, verbally. Just after it caught fire. Hooked up a 32 amp device through 16 amp cable. But seriously. I have PSU’s all over the place that way i have hardly any loss. Everytime i saw an old pc next to the garbage i took the PSU out. Must have dozens lying about.
    The longest distance from PSU to device i have is about 10 yards. But then again french provencale houses are tiny.

    I have everything and the kitchensink hooked up to my pc, which with a couple of 16 channel USB adapters drives my wife berserk. She hates it when she turns up the light and the computer turns it down again to ambient 30 seconds later.

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