This week, I&#;ve attached two more lightbulbs to my network, because&#; apparently this is what you do with lights now. I&#;ve hooked up a pair of Philips WiFi bulbs, and run their output into my spectrometer to see how they behave and what&#;s going on with their emissions.
BMT supply professional and honest service.
I grabbed two different bulbs - one that&#;s simply a color temperature shifting white bulb, and one with the full RGB emitters (in addition to the color shifting white emitter) and proceeded to poke/prod/analyze them.
I&#;m not quite sure what Philips is doing with bulbs, because they sure seem eager to sunset old bulbs (the Hue series comes to mind, as does the Warm Glow stuff I&#;ve used). But these are, as of early , what they sell as &#;smart bulbs.&#; They&#;re 2.4GHz only WiFi bulbs, have the required App(TM), and do things. On the left, a full RGBW bulb with color temperature shifting, and on the right, just the color temperature shifting version. They look like almost all the other LED bulbs.
They&#;re rated 800 lumens at 8.8W, which&#; sure, I don&#;t have the equipment to test either one exactly, but it&#;s probably close enough. I&#;ve got my questions about how 100mA at 120V works out to 8.8W (seems like 12W to me), but there may be some rounding regulations on amp ratings to avoid claiming something pulls 74mA. It&#;s also worth pointing out that an older style 60W incandescent will put out about 860 lumens - so comparing lumenous efficiency, it&#;s a factor of ~6.35x improvement. One can reasonably expect around there - 1/6th the energy per lumen for a LED bulb vs an incandescent, but if someone starts going on about how LEDs use orders of magnitude less energy, call them on it. One can safely assume 1/5th the power and be largely right, some are better, but I&#;ve yet to see a production bulb using 1/10th the energy of an incandescent.
The other side includes some standard enough LED warnings that you might consider pondering. &#;Do not use with dimmers!&#; is normal enough (though I&#;ll explain what that actually means later), but &#;Not for use in totally enclosed or recessed luminaires!&#; is related to why a lot of people observe LEDs failing early in actual practice - most homes don&#;t have bare bulbs, they have recessed or enclosed fixtures. A lot of LEDs aren&#;t rated for these fixtures - and will overheat in operation. Unlike an incandescent, the power electronics in the LED bulbs really do care about running temperature, and a lot of them are &#;rather poor&#; at getting rid of heat. Crank your electronics up a couple dozen degrees above design temperature, your service life will end up being very poor - as many people are learning. Some LEDs are rated for enclosed fixtures, and you should probably buy those.
The boxes will usually tell you as well. If it says this, don&#;t buy it. K?
This may, at first glance, seem a weird set of posts for me. Why do I suddenly care about smart light bulbs, or LED color spectrums? The long form answer to this can be found in a previous post of mine, How Your LED Lights and Screens are Killing You. Our modern white LEDs emit quite a bit of blue, squarely in the regions of spectrum that the human eye uses to determine if it&#;s daytime (about 440-490nm). At their core, they&#;re a blue LED with a phosphor coating, and some of that blue leaks past. Some lights emit more, some emit less, and since I now have a spectrometer, I&#;ve been pointing it at a range of bulbs to better understand how much blue they leak in various modes.
If you&#;re struggling with sleep at night, my advice is to be very careful of the blue light after dark. I&#;ve gone back to incandescent light sources on dimmers in areas I use at night, with some very real improvements in how quickly I go to sleep and how well I sleep. At a minimum, you should ensure all your LEDs are &#;as warm as possible&#; in light after sundown, but even from there, they tend to still leak a lot of blue compared to an incandescent light source.
I&#;m starting here with the white bulb, which has two controls: Dimming and color temperature. This bulb is capable of ranging from K to K, and it dims, though not particularly well as far as I&#;m concerned. I like a dimmer to be able to run a bulb all the way down to zero, and there&#;s no good reason a bulb that&#;s always powered can&#;t do it - but this one doesn&#;t, just like any others. You can control the light color shift and dimming in the app, and it works fine.
Starting with the K setting, it looks like an LED. Blue bulge starting in the 450nm range, with the bulk of the emissions coming off the phosphor coating that&#;s being driven by the LEDs. The major surprise here are those spikes over in the reds, up past 600nm. There are three spikes over there, on top of the normal curve. It looks a bit like my iPhone SE&#;s behavior in the reds, but it&#;s certainly not something you pick up with your eyes. Both of the Philips bulbs do this when their white emitter is running.
As the color temperature goes up, there&#;s obviously going to be more blue - but the biggest surprise to me was just how much of a difference going from K to K made. Just that tiny 300K tweak in color temperature added a ton more blue squarely in the regions that matter.
There&#;s no surprise - as the color temperature gets warmer, the amount of blue just keeps increasing. This K setting is the typical &#;daylight&#; setting for a bulb.
And finally, up at the maximum color temperature, K is what you&#;d expect to see. Lots more blue, lots less &#;everything else.&#; Even the red spikes have started to drop very noticeably compared to the blue and greens up here. This is a great mode to help wake you up in the morning, and an absolutely awful mode to be using at night. There&#;s no real harm in blue during the day, and if anything, we need more blue light during the day to compensate for the lack of sun most of us get. But you absolutely don&#;t want to be using settings anywhere near this at night, because they will keep you awake through suppressing melatonin production, with all the nasty consequences of that.
Overall, the &#;color temperature changing&#; white bulb does what one would expect it to do. It&#;s probably fine during the day, but even in the K setting, there&#;s a lot of blue leaking at night - so, at a minimum, keep it dimmed.
Far more interesting is the behavior of the RGBW bulb. In addition the white emitter, this bulb can do the whole &#;Show any color you want&#; trick that&#;s popular in smart lights. Plus, it claims an increased color temperature range - it can be adjusted from K to K (vs only down to K on the other bulb).
The app allows you to set colors either as hex values, or with a color wheel. Towards the center of the wheel, colors are mostly white, with some tinges of other colors, but as you get out to the edge the saturation increases. Usefully, this app will show you the hex value (RGB) it&#;s trying to emit.
There are a lot of other things the app can do, and I simply don&#;t care. You can find a review of the app somewhere else. I use it to drive the bulb into the states I want to measure, and that&#;s it.
Starting out, I set the bulb to K in the &#;white bulb&#; mode, expecting to see the same thing I saw with the previous bulb, and in fact, they appear to have the same emitter. As expected, so far. The red spikes, the blue bulge squarely in the human blue light sensitivity region&#;
What happens when you set the bulb down to K? It looks a lot redder&#; but as the spectrum shows, nothing has changed except that it&#;s added a ton of red. The blue emitter, the phosphor curve, they&#;re all exactly the same as at K, but the red LED comes on to add more red. Color temperature is nothing but an average of the spectrum as it appears to the human eye, and it can&#;t tell you anything about the actual distribution of energy throughout the spectrum. You might think that setting the bulb down to K would reduce the blue, but it&#;s done nothing of the sort. It just adds more red energy. Again, visually, this works, but if you&#;re looking at the actual blue that screws with sleep, it&#;s changed nothing. You might be able to dim the bulb a hair and reduce the blue, but fundamentally, it&#;s just adding some red LED into the existing mix.
Up at the upper end, nothing else changes either. It appears to be the exact same white LED emitters in both bulbs - the curves are almost identical. This shouldn&#;t be a surprise, they&#;re the same company, and the same general category of bulb. Nothing too interesting there.
Moving onto the RGB modes, the first major surprise is that in the &#;white&#; center of the spectrum wheel, this bulb is using the white emitter. The Feit I reviewed would either run the white emitter or the RGB emitters, but not both. The philips blends in the white emitter as needed to produce the desired light color. Here, it&#;s more or less centered in the color wheel, and looks a lot like the K spectrum - which, visually, is about where things are.
Where this gets interesting is that as you shift the colors around (in this case, out towards the orange), the bulb starts by simply starting to color shift the white spectrum - this is a pale orange, and you can see the rise in the reds, while the rest of the spectrum is still clearly the white emitter purring away at the center.
As you move further out, towards a more saturated orange, all of a sudden the light shifts modes. There isn&#;t any clear visual indication that it&#;s done this, but now, despite the light still being a pale orange, the white emitter has dropped off and it&#;s now in pure RGB mode (you see the three spikes, and the blue peak has shifted up noticeably). Look at the spike in blue compared to the above - despite being a more saturated orange, there&#;s a radical increase in the blue coming out of the bulb. In this case, the whiter light actually has a lot less blue in it.
Keep going out, and eventually you hit a fully saturated point, in which there&#;s no blue left - but the transition from the white emitter to the RGB emitters really spiked the blue hard. There&#;s no guarantee about what it&#;s putting out, without actually having a spectrometer to see what the bulb is doing.
Though I will say that when the RGB value has &#;00&#; in the blue field (the last two digits), it seems that the bulb really is blue-free. It doesn&#;t mean you can make nice colors out of it without blue, but it also seems to very much obey the hex values in terms of the light intensity in each of the colors.
Looking at each of the colors separately, blue seems to peak somewhere right around 468nm. Squarely in the middle of the &#;bioactive blue regions that suppress melatonin,&#; and, in fact, this is almost a perfect overlap with some of the observed sensitivity curves. Great to wake you up during the day, not so good in the evenings.
Green peaks right about 524nm - not a bad place for green to be.
And red seems to peak, at least given my meter&#;s sensitivity (which is dropping off by the reds), right around 621nm. If you want to play Hunt for Red October, the red off this light will work perfectly well for that!
But, you can see in these graphs very clearly that the bulb obeys the hex values - it does, once you&#;re out in the saturated rim, do what you told it to do. And that&#;s nice to see!
Do not dim? Why not? I attached these bulbs to my little dimmer adapter, and proceeded to dim them.
The &#;color shifting white&#; bulb actually obeys dimming reasonably. As you dim it down, it gets dimmer - but it also is prone to a rather noticeable flicker when dimmed below about 50%. If you&#;ve dimmed it in software, it&#;ll still dim more on the dimmer, but it hunts around a good bit - it&#;s not a consistent behavior.
The full color bulb does about the same thing when in the &#;white LED&#; mode, but if you&#;ve got it in the RGB color mode, it is utterly undimmable - as you dim it slightly, it just glitches out and reboots.
So, I agree! Do not dim. It seems the white emitters share at least some of the electronics with their dimmable bulbs, but not enough to be able to reasonably dim them. Full power, only!
One of the obvious questions people ask with my research into lights is, &#;Well, how are the smart bulbs? You can just color shift all the blue away, right?&#; - and while you can make some major differences, the nuances of shifting away from the white emitter and onto the RGB emitters have some serious reversions, and unless you just want your house somewhere in the &#;green, yellow, orange, red&#; shade of things, I don&#;t think these bulbs are managing to do anything special. They&#;re a standard color shifting white emitter with some RGB bits that kick in, but I&#;m still not exactly sure what problem they&#;re trying to solve beyond &#;Add more apps to people&#;s devices that require location data,&#; and &#;Keep 2.4GHz WiFi Working.&#;
If you really have some desire for smart bulbs, I guess you could find something useful to do with them, but you&#;ll be making your house colors best suited to a college party, not any reasonable living space. I still find these things a solution desperately hoping someone will believe they&#;ve got a compatible problem.
I bought 25 of the best-selling soft white LED 60-watt equivalent light bulbs on Amazon and if you&#;re only interested in my conclusion, the Philips Ultra HD 60-watt equivalent is the best lightbulb on the market, and it&#;s not even close.
I&#;ve got a link to that bulb below but stick around if you&#;re interested to see why it&#;s the best as I compare all 25 LED bulbs to a 60-watt incandescent bulb, a 60-watt equivalent compact fluorescent bulb and this ultra-high end LED bulb that I paid $22 for. As always there are no sponsored reviews on this website, I bought all these bulbs with my own money, and all the values that I report are the results of my own testing rather than relying on manufacturer claims.
In the first test we&#;ll measure their efficiency by comparing their advertised power draw and brightness to their actual values.
If you are looking for more details, kindly visit philips automotive led bulbs.
After that we&#;ll look at their color rendering index and light emission spectrum.
Then we&#;ll see which light bulbs have the least amount of perceptible flicker.
For dimmable bulbs we&#;ll test the uniformity of their dimming curve.
And last, we&#;ll take each bulb apart and examine the circuitry to estimate how long each bulb should last before a component failure.
The main reason to use LED light bulbs over incandescent bulbs is energy efficiency, or the amount of light that they generate per watt of power. Based on their packaging and Amazon listings, the bulbs claim to generate between 76 and 100 lumens of light per watt.
Using a power monitor and lux meter combined with my highly sophisticated LED testing enclosure, I found in most cases the bulb&#;s measured efficiencies were close to their stated efficiency, and most of the bulbs produced between 90 and 100 lumens per watt, with the GE bulbs performing especially well with efficiencies around 115 lumens per watt, which is about 20% more than the average.
However, compared to other types of lighting all the LED bulbs were ultra efficient, performing % better than the incandescent bulb I measured which had an efficiency of 7.2 lumens per watt, and 230% better than the compact fluorescent bulb I tested which output 41.6 lumens per watt.
I also specifically purchased bulbs that were labeled as soft white, but it appears that terminology isn&#;t completely standardized since some soft white bulbs were labeled as Kelvin while others were a slightly cooler white color at Kelvin. After testing I found there was a significant variation in color with the Phillips Ultra Definition bulb coming in with the warmest color temperature at Kelvin, which was the most similar to the soft white incandescent bulb I tested.
The most accurate color temperatures were from the Energetic Non-Dimmable bulb and the Regal bulb which were within 5 Kelvin of their stated K temperature.
However, not all K light sources are equal, and one of the main complaints about LED lighting is that they have a large blue spike in their emission spectrum which can negatively affect sleep patterns. The blue spike is due to the fact that the LEDs themselves actually give off blue light, and then use a phosphor coating to create the rest of the spectrum.
For reference, here&#;s the emission spectrum of an incandescent light bulb where you can see how much energy is wasted emitting light in the invisible infrared spectrum. Here is the ridiculously spikey and uneven spectrum from a compact fluorescent bulb, and this is the emission spectrum of a typical LED light bulb with a relatively low red output and significant blue spike.
I tested the emission spectrum of every bulb and found that the Linkind, Sylvania, and DiCuno bulbs had notably low blue spikes, but the lowest blue spike was from the Philips Ultra Definition bulb. These numbers are also closely correlated to color temperature, though the GE Relax bulb was able to generate very close to K color temperature without a large blue spectrum spike, which is what that bulb is designed to do.
Blue light effecting sleep patterns isn&#;t the only problem with uneven and spikey color spectrums, because in real life different objects may reflect or absorb only a specific wavelength of red, green or blue, and if that frequency isn&#;t emitted by your lightbulb, then the color of those objects won&#;t look right when lit up by those bulbs. The term for this concept is the bulb&#;s Color Rendering Index or CRI and it represents how accurately a light will illuminate the full spectrum of colors.
Most of the LED bulbs claimed to have a CRI above 80, while the Philips Ultra Definition bulbs and the super high end WaveForm LED bulb claimed to have a CRI of 95, and some bulbs like the one from GE didn&#;t make any CRI claims at all.
In this case the $22 WaveForm LED bulb had an impressive CRI of 96.5, which is actually slightly better than the incandescent bulb, but the $3.50 Philips Ultra Definition bulb was only 0.4 behind that at 96.1.
Both the WaveForm and Philips Ultra Definition bulbs specifically struggled with the R9 color, which is a pure red color that tends to be difficult for LEDs to correctly render due to their lower emission in the red spectrum.
For reference here&#;s the CRI report for the incandescent bulb, which as you can see does a much better job with reds due to its heavily red shifted emission spectrum.
The DiCuno bulb also performed very well with an average CRI of 91.4 which is impressive for a lower cost bulb, and you can see it struggled in the same R9 test, but also had lower values for R10 and R12 which are in the yellow and blue spectrum, but 91.4 is still an excellent score for a $2 bulb.
Another critical argument made against LED bulbs is that they can flicker, which is caused by the fact that our electrical grids use alternating current or AC. In the US, our grid runs at 120V 60Hz AC which means it actually oscillates between +170 and -170V, passing through zero volts 120 times per second. Whenever it crosses that zero line it means no voltage is present and no power is delivered to the bulb which means even an incandescent lightbulb turns off 120 times per second.
However, the important aspects for our perception of flicker are the difference in the brightest and dimmest value which is represented by % flicker, and the difference in total light output at the average brightness compared to the light output above the average brightness which is called the flicker index.
An incandescent bulb&#;s flickering is almost imperceptible since it&#;s light is the result of the superheated tungsten filament, and when the voltage drops to zero for a split second that filament stays pretty hot, meaning the depth of the flicker is minimal. Using a specialized flicker meter I measured the incandescent bulb at a 9.5% flicker percentage, but only a 0.03 flicker index which is very low.
Lots of the bulbs were advertised as &#;flicker free,&#; but the $22 WaveForm bulb was the only one to actually live up to that claim. You can see the difference between the brightest and dimmest point was less than 1% and the flicker percentage was also under 1% leading to a flicker index of 0.00, so low that the flicker meter occasionally stopped detecting any flicker at all.
The only other bulb that outperformed the incandescent was the Philips Ultra Definition bulb which had a 6 times lower flicker percent at just 1.5%, and also a 3 times lower flicker index of just 0.01, which isn&#;t as good as the WaveForm, but still extremely impressive and it does all that while still being a dimmable bulb, which the WaveForm is not.
Speaking of dimming, modern dimmable LED bulbs work well with modern dimmers, but I&#;ve heard the complaints that the dimming curve is uneven, that they don&#;t get dim enough, or what I&#;ve personally experienced is that at the dimmest level there is a noticeable brightness fluctuation, different than flicker, but definitely noticeable. To test this, I set up a Shelly dimmer and measured each bulb&#;s brightness at 5% and 10%, and then 10% increments all the way up to 100% and mapped their dimming curve. I also visually inspected each bulb at 5 and 10% brightness for any noticeable brightness fluctuation.
The only two bulbs to resist brightness fluctuations at 5% and 10% were the incandescent bulb which had a minimum lux value of 22.6 at 10% but didn&#;t turn on at 5%, and the Phillips Ultra Definition bulb which turned on at 5% with an extremely low lux value of 4, and at 10% it output 225 lux, again with no brightness fluctuations.
Only the Philips, GE Relax, and Linkind bulbs were able to turn on below 10%, and of those, the Philips was the only one that had a stable dimming curve that didn&#;t plateau after 70%.
So, recapping all the tests so far, out of the affordable brands the Philips Ultra Definition bulb performed the best in every category except efficiency, where it still surpassed the average and was within 1% of its advertised lumens per watt.
But as I was explaining the extreme superiority of the Philips bulb to my wife she said &#;that&#;s great, but the one that is the best to me is the one that lasts the longest&#;, and that&#;s a hard thing to test since unlike the hours of life expectancy for an incandescent bulb, LED bulbs are supposed to last 20 to 30 thousand hours, but if we know how these bulbs typically fail we can make a good guess at how long they should last based on their internal components. Mostly.
I took apart every bulb that I tested and the majority of them look like this with a ring of LEDs, a bridge rectifier, a smoothing capacitor and a current regulating chip. Each LED in the ring is actually 1, 2 or 3 smaller LEDs in a package that then gets covered with that yellow looking phosphor to create white light.
On these circuits you can generally predict their reliability based on the number of LED chips since more LEDs means that each one has to drop less voltage and will ultimately generate less heat, which is the killer of LEDs. In this regard I was most impressed by the Great Eagle 800 Lumen bulbs that uses 24 LED packages per bulb but still only cost $1.33 each.
However, things get complicated with the Philips Ultra Definition, GE Classic, and GE Relax bulbs which have the same current regulating circuitry but use filament style LED packages in a glass enclosure instead of having the chips soldered to a circuit board.
However, knowing that heat is the killer of LEDs I tested the Great Eagle 24 LED bulb vs the Philips Ultra Definition by running each bulb inside the testing enclosure and recording the temperature after an hour. You can see the Great Eagle 24 LED bulb is about 112 degrees Fahrenheit on the plastic shell but was over 200 degrees at the base which is where it dissipates its heat. However, after an hour the Philips Ultra Definition glass bulb was just 109 degrees at the top of the bulb and 117 degrees at its hottest point, meaning even after an hour it was fine to handle with my bare hands. This means that the Philips bulb either overall generates significantly less heat or does a better job dissipating that heat through the glass shell and metal base. Either way the lower overall temperature of the Philips bulb suggests that the filament style glass bulb will last longer than a traditional aluminum circuit board LED bulb design.
I also ran the same hour-long test with the $22 WaveForm LED bulb and found that although it had the same heating pattern as the Great Eagle, the base never got over 185 degrees before the current regulating chip lowered the power to the LEDS from 9.5 watts down to 8.9 which prevents overheating.
So, as I said at the beginning of the video, the Philips Ultra Definition bulb is by far the best lightbulb I tested, and it&#;s not even close. Just to be sure of their quality I also tested an additional package of the soft white 60-watt bulbs which performed equally well, and I ran a set of their K color temperature bulbs through the whole set of tests and they also had extremely low flicker, great CRI and a nice linear dimming curve. At $3.50 per bulb, the Philips Ultra HD bulbs are getting close to a premium price tag but are well worth it in my opinion.
On the other side of the spectrum the WaveForm lightbulbs did undeniably well, with their zero flicker, great CRI, and 25% more light output than the Philips Bulb, but they did consume 35% more power than the Philips, they aren&#;t dimmable, and also cost over 600% more per bulb which doesn&#;t seem worth it for such a small increase in performance.
For something on the cheaper side, the DiCuno bulbs maximize CRI and limit the blue spike for $2.00 each, but had a high amount of flicker. If you don&#;t care about CRI and just want low flicker the Partphoner bulbs had a relatively low flicker index for just $1.33 each, and if you&#;re looking for a cheap bulb that will last a long time and you don&#;t care very much about the quality of light then the Great Eagle 800 Lumen bulbs put the smallest load on each LED for just $1.33 each.
Links to all the bulbs from this video are below and as always I appreciate if you use those links since as an Amazon affiliate I do earn a small commission on the sale at no cost to you.
If you want to learn more, please visit our website philips automotive lighting.