THIS LAMP SOXs! "Yellow" tech of bright metal vapor lamp. Beats modern LEDs in brightness per watt?

[@nilz23]

That single spectral line must be what those city light filters for astronomy were meant to take care of, and why they don't work anymore now that most street lights are white LED.

[@Warp2090]

It's a shame most streetlights are LED's. They hurt eyes at night so much, and are ugly

[@brainiac75]

Yep, need to make a video about that. The 589 nm line is easily filtered out by glass doped with neodymium 3+ ions. I have some of that glass but haven't tried it yet. Should work really well. Thanks for the early comment and watch!

[@TheCORC964]

Love sox lamps, I miss when the streetlights were all sox the light was so much warmer and more cosy especially in the winter. Not to mention they lasted longer than the LEDs they’ve been replaced by 🤦🏻‍♂️

[@Muonium1]

The filters were made of didymium glass and work for the exact same reason glassblowers still use them as lenses in their safety glasses - their remarkable ability to selectively notch out the bright D line radiation while transmitting most of the rest of the visible spectrum.

[@DigBipper188]

That's precisely it. due to the highly monochromatic light output from these lamps you could just filter out any wavelengths between 588 and 590nm and be good to go. With white LED since they are polychromatic that same filtering is next to impossible to do because you're also filtering out wavelengths of interest. For that reason, monochromatic variants of standard LED fixtures are also being trialed to replace SOX as the supply of fresh lamps dwindles and old fixtures start failing. we already have fixtures that output only one single wavelength in the red spectrum and I think there are also some designed to only emit 589nm to replace SOX near observatories as well. Sad to see SOX technology fade into obscurity though. I'm a Brit, and with special thanks to the energy crisis in the 1970s, SOX became ultra commonplace in our road lighting schemas up until the 2010s when they started to be phased out for high pressure sodium and ceramic metal halide and now LED alternatives.

[@truckerallikatuk]

Those sodium lamps were only ever designed for object avoidance on roads and footpaths. For this, they're perfect. And in fact, in some ways better than white light, for example, astronomers could filter the sodium discharge out.

[@MattyEngland]

Yeah I preferred the look of the old sodium. A lot less harsh on the eyes.

[@seth094978]

I find my night driving vision with sodium vapor to be significantly better than with LED. I feel like I can see into the shadows better, the light fall off feels less harsh.

[@brainiac75]

Yes, not designed for indoor use for sure :) Need to make a video about why astronomers miss these lamps... I think the sodium lamps also have less impact on our adapted night vision. The white LEDs just wash out our night vision so our eyes need to adapt to the darkness when driving out of a city... Thanks for the early comment and watch!

[@Peter_S_]

LOX lamps were used until somewhat recently on the Golden Gate Bridge in San Francisco. The yellow light is burned into my memories.

[@MadScientist267]

Yeah involving CRI is only an after thought when identification of things like car colors and what not became a thing. They certainly weren't for the view. It was a practical consideration. There's a reason they have so much reach and that a wider spectrum lamp can't perform anywhere close to them... the energy is spread out. You can't have it both ways.

[@pheasantplucker]

So 589nm is the colour of my childhood? That explains a lot!

[@4bSix86f61]

The color of limital spaces and the backrooms

[@TushhsuT]

589nm is not a color - it is a wavelength. So - 589nm is the wavelength of your childhood :)

[@pheasantplucker]

@@TushhsuT It looked a hell of a lot like a colour from where I was standing (in my childhood).

[@luminousfractal420]

​@@pheasantplucker😂 👌

[@alexturnbackthearmy1907]

@@christopherneufelt8971 They were quite literally everywhere, on every street corner. I still miss that cozy yellow light.

[@JeffBilkins]

I strongly associate this glow from when I was a kid watching the strings of highway lights during late-night car travels.

[@hinz1]

Being a kid in the 1960-1990s certainly was better, wonder what nostalgia kids from nowadays have. The days before skynet/AI took over the world, maybe??

[@gravyboat2370]

Happy memories

[@lajya01]

I was so sad when the DOT replaced the old catenary sox lamps with high mast LEDs on a stretch of highway I used to drive with my parents.

[@blaircox1589]

These new LED lights are horrible. Yeah, sure new lights render colour - but FAIL at detecting objects at distance around the streetlight. I read somewhere that our eyes at night can see better with a warm glow similar to candlelight. But these new straight Blue LEDs only create isolating pockets of light where it's a sharply defined edge between seeing a person standing and stepping back a few feet and disappearing. Plus now we're bombarded with blue light at night affecting sleep.

[@mernokimuvek]

@@hinz1 I was born in 2001 and I miss seeing high pressure mercury vapor and metal halide lamp fixtures. The beauty of the old times was the various light sources. Now it's a boring place with mostly L*Ds.

[@gblargg]

Those sodium vapor lights are interesting at night. Many a night I played under them. You adjust to it quickly. And it's the right color for night, to stimulate sleep.

[@balsalmalberto8086]

Importantly no blue.

[@luminousfractal420]

​@OnyxtheFolf just wait for the 150ft led billboards on the roads. when someone advertises something with a white background you can see all the way to neptune. really bad.

[@willchalloner706]

As a child in the late 80s and early 90s i was fond of watching the lights on the motorway or the street at night flick on with that pinkish glow. Sometimes you would see one that was stuck in that pink phase, that was a real winner.

[@AB-Prince]

when I used to work for a telescope factory, they used SOX lamps for their exceptional monochrome spectrum. spesifically they used it for the newtons rings . in that instance they were using it to check the flatness of the angle mirrors.

[@Graham_Rule]

I miss the yellow of the Sodum D lines. They were great for adding light to nighttime streets and paths without being too much like daylight. After all, a path lit by only moonlight doesn't have any colour either. We seem to have gone all out to make every road, path, or park as close to daytime and I miss the dark.

[@RUS38]

Parasites are doing everything in their power to irritate us and put stress as much as possible on all levels.

[@belken117]

Sodium vapor lamps are among the key ingredients to what made Disney's film Marry Poppins animated characters and painted background! ^^

[@brainiac75]

Huh? Never realized this. Thanks for the tip! Yellow-screen was the early green-screen :D

[@frogz]

greensc.....yellowscreen!

[@BrokeInfinity3309]

@@brainiac75 Try watching the corridor crew video about this!

[@LtKernelPanic]

Yep. I recently saw a really cool video how someone recreated it using two cameras and modern filters instead of the special one that used two film strips and a beam splitter with special coatings. The difference between it and the current green/blue screen process was amazing.

[@MadScientist267]

Yep it is much cleaner

[@mfbfreak]

The higher powered SOX lamps can be much more effiicent. For instance, a 1980s 135w SOX does a whopping 160 lm/w, and a 2000s era 91w SOX-E even makes it to 192lm/w. The little 18w one is the worst of the bunch efficiency wise, but back in the day absolutely the very best way to efficiently light small outdoor areas. I have two of them, there's video on my channel about starting them on a 15w fluorescent lamp ballast with a glowbottle starter. The lamps themselves are still in production in the far east and available at (among other places) DBL Verlichting. One important thing anyone who wants to play around with them should know is that they are absolutely not allowed to be run with the base down. AFAIK all of them can run horizontally, the small ones also vertically base up, but check the datasheet of the lamp for specific information about the required running position. When run in the wrong position, the sodium will condense onto the wrong surfaces (like onto the electrodes when run base down) and either destroy the electrodes, or be unable to be vaporized anymore.

[@DigBipper188]

Anything below 55w SOX / 36w SOX-E can be run vertical base UP or horizontal +/- 110 degrees. Running them base down allows the sodium to pool around the cathodes and will result in the area near the cathodes cracking from differential heating and cooling of the sodium. it can also result in the cathodes being coated with the sodium which can prevent the thermionic coating (which is responsible for reducing the voltage needed to strike and maintain continuous discharge) from evaporating off, resulting in the lamp being hard to start if it starts at all. For larger lamps over 55w they need to be run horizontal +/- 110 degrees and shouldn't be operated base up. This is because the vapor pressure inside the lamp is sufficiently low that all the sodium vapor will pool at the lower end of the lamp and result in an unequal vapor distribution, reducing the lamp's efficacy.

[@LRK-GT]

I'm curious. How did these SOX lamps handle vibrations? A dream of mine is to somehow mount a high-output SOX array to a vehicle. But, I'm expecting off/on-road vibrations make the concept a non-starter.

[@DigBipper188]

@@LRK-GT I'd advise against it for offroading. You might get away with it if the lamps you use are framed with metal but modern SOX lamps especially use mica spacers to mount the discharge tubes. These would easily start to disintegrate with constant harsh vibrations. same goes for high wattage lamps but also with the additional problem of the fragility of the discharge tubes. it wouldn't be hard to shatter one of these lamps with one solid bump.

[@mfbfreak]

@@LRK-GT Unadviseable. They're not particularly sturdy things, with a long glass tube within another glass tube. SON (high pressure sodium) lamps have a smaller, more lightweight internal construction and will be able to handle vibrations better, but they still are designed for stationary use. You can try it, SON lamps are dirt cheap by now. Because SON also has *some* green rendering, it will also make it easier to differentiate between the track and the foliage next to it. But i still recommend against it - go for metal halide or led instead, the warmest white you can get to avoid wrecking your night vision.

[@mernokimuvek]

The same is true for fluorescent lamps. Lower power, shorter fluorescent lamps are less efficient because the electrodes losses(cathode fall) is nearly the same, so a lamp with a higher arc voltage is more efficient. This is even more significant in cold cathode lamps which operate at several kV.

[@jensschroder8214]

These yellow lamps have one advantage. They glow monochrome in a light that insects cannot see. No irritated insects fly around these lamps. For the human eye it corresponds to seeing in black and yellow.

[@Techno-Universal]

Disney also took full advantage of that for a new revolutionary green screen technique that even allowed for perfect transparency! :)

[@herzglass]

That I can not confirm. I lived in a street with sodium lights as kid and they were surrounded by clouds of insects. The new white LED street lights around me today, do not, which is why now, when I open a window with lights on, I get way more insects into my room, than as a kid. Insects do care for yellow a lot, and modern LED street lights, filter out narrow bands that nocturnal insects care for.

[@Techno-Universal]

@@herzglass That’s also because they think it’s sunlight and are trying to point their backs at it for navigation! :)

[@BruderRaziel]

This is false, the opposite is true: One of the color detecting pigments bichromatic insects have actually peaks in the 550nm-590nm range.

[@LRK-GT]

I have a nearly unhealthy fascination with these Low Pressure Sodium lamps. I'm not even into photography, and feel like a whole swath of lighting technology was taken from us. IIRC, these lamps' output were much less 'harmful' to night adapted vision. While they 'nuked' your color vision, you could make out details in the light well, and drive/walk into/out of darkness w/o the irritation of transitioning to/from high LED-illumination. NtM, SOX did not 'mess with' people's circadian rhythms like HPS, Mercury Lamps, and LED. Especially, knowing that well-developed SOX lamps well-exceed to nearly-match LEDs' efficiency (past-now), I feel like their removal from the market had nothing to do with energy efficiency.

[@Aim54Delta]

Most western nations have the facilities to make incandescent and metal vapor lamps. Virtually all of the investment into LED manufacture has been foreign/abroad and their stock holders have a disproportionate representation in legislative branches of government. It's mostly about the money and political/economic control. At first, it may appear to be a "get rich" scheme in politics, but it's more about isolating and controlling economic supply lines within ideological lines. If only a few factories manufacture the legal form of lighting, then the lighting around the world is controlled by those who own those factories or networks thereof - they can decide what they want and everyone else has to follow, unless they want to be criminal scum or something.

[@eriottomakurashi]

⁠​⁠​⁠@@Aim54DeltaI understand from where you are coming from. It would be fair with something like food to reach that conclusion, yet, lights are not as… locally dependent. You don’t need a good soil, climate, region to produce lightbulbs; this means that competition can rise from anywhere where the investment is. I am not familiarized into bulbs or lasers manufacturing so I may be assuming too much, it is just that political string pulling seems unrealistic for light bulbs. Might be that there were reasons to believe that a more competitive lightbulb could be made, cheaper prices for production for example, but then again, I am just eyeballing this without any real insight into the long history of the bulbs

[@Aim54Delta]

@@acmhfmggru You would be somewhat correct were it not for the fact that people with the legal right to murder you will show up if you manufacture, sell, or use these lights in many parts of the world. In factories, for example, LEDs are generally garbage when replacing high-bay lights. On paper, they are better, but in practice, the elevated temperatures cut their lifetime by 90% or so. In the case of street lights, the advantages of LEDs are questionable. As for manufacture - if it was really that much more simple to manufacture LEDs, then why are there no LED manufacturers in the U.S. for example? These are extremely sophisticated pieces of machinery used to manufacture modern LEDs and which require an array of supporting industries. Compared to glasswork and sodium metal, they are orders of magnitude more complex to manufacture, that is partly why it took us an additional 50 years to develop the ability to do so. People are correct to arrive at the conclusion that useful things are being taken away from them in an unnatural manner. Why did they ban asbestos? Because it worked. What did they replace it with? Stuff that didn't work as well and causes the same problems if you grind it into dust and inhale it. Lead paint and gas ... Okay, you get a pass on those, but the effort to ban oil based lubricants and paints for water based ones runs into the same thing - the old stuff worked, so we have to replace it with something that doesn't ... That we own stock in ... And then find it is just as bad if not worse in terms of health/environment.

[@KhooTengKwang]

@@Aim54Delta Dude, Asbestos causes mesothelioma(a form of cancer). No one's just gonna ban stuff that works well for no reason. There are products that could cause harm like the materials used in the production of Teflon. Some things that work well can end up causing harm to others in the end or have some sort of flaw that necessitates finding an alternative. Besides, if powerful people find something that works well but causes problems to people or the environment, odds are, they would resort to underhanded tricks to KEEP it's CONTINUED USE, even at the detriment of others. Why waste an opportunity to profit when it works SO WELL?. So it ain't a problem of powerful people trying to do something funny. There are just people who just recognize that certain products, no matter how good, that cause problems for people like health problems or other things and decide to do something about it by finding an alternative. The unfortunate thing is, it's hard to find a better alternative to the thing you're trying to replace.

[@Aim54Delta]

@@acmhfmggru Motivation is the master of reason. It's not a shadowy cabal, they openly stand up and proclaim themselves as humanity's savior and campaign on a crusade against the past. For those who pride themselves on being informed and intelligent, they do not want to see their world as being run by corrupt fools. They like the narrative and the irony of a holy crusade against religion or any perceived lack of allegiance to "science" or some similar touchstone idea. Consider, rather than arguing the point about whether or not LEDs are truly as "better" as they look on paper, you sideline away from the obvious fact that it is outright illegal to sell older styles of lights in many parts of the world while asking me where the shadowy cabal is. Obviously, they wrote the law. It's your own motivation which blinds you to its existence. If these technologies were so much more simple and economical, then why would a law be necessary for them to gain widespread adoption? If the argument is that the government must "steer the market and coerce adoption/innovation" - then you don't see the shadowy cabal at all, because they are the ordained ministers of righteousness in your mind. The problem is, as I would suspect, you are vaguely aware that the majority of the public would not see such as righteous - likely because you think they are simply ill informed or clinging to religious pretenses best left in the past to be destroyed. Hence your motivation to effectively try to gaslight people on the subject. Evil doesn't come in cackling serpentine forms. It comes in the purest white and the most intoxicating of bliss.

[@paranoiia8]

Its not that horrible.... its nice, warm. Remind me of warm summer nights back in 90 and all good memories of it :D

[@GenosseRot]

With such a powerful sodium lamp you could try to create "black fire" that also creates a shadow. Try it out! Take an ethanol based burning paste (for heating the food on a buffet), give into a bowl and sparkle a lot of sodium chloride over it. In a dark room it will burn with a bright yellow light (same colour as your light bulb) but in room with only your sodium light bulb the fire should be appear to be black and also to throw a shadow. This happens because excited sodium ion don't only give off yellow lights but sodium ion in ground state can actually absorb exactly this yellow light. And even in a fire a vast majority of sodium ions are in the ground state. So absorption will overcome the emission. This is so fascinating to see.

[@Funnyboy2402]

This light was installed in many public toilets in the 80 and 90 to avoid narcotic use there. It makes it almost impossible to see the blodvessels in the arm.

[@dancoulson6579]

Do you remember when they also used the blue colored fluorescent tubes for the same reason? I think they switched to blue, because blue gives the impression os cleanliness too... If you see some kind of blue liquid you're not grossed out by it, because it's not a color you see much of in nature. Where as if you see a bile green, or booger yellow, or poop brown colored liquid in the same context you're much more likely to consider it dirty.

[@mduckernz]

… of course, it doesn’t actually prevent that use, it just makes it really destructive when it does occur.

[@MartinBalle7]

I was about to write that. The first time I was in bathroom where they used this kind of lamp, I got a headache from my eyes trying to adjust to it

[@abrunosON]

The opposite of those lights are used in prisons to be able to see bruises.

[@monad_tcp]

@@mduckernz and then everyone can look at the person doing that to themselves and ostracize and shame them very easily, objective successful (more like successfully failed)

[@videolabguy]

Great video! Thanks! When I was 8 years old, I went to a friends house down the street. I parked my bright red bicycle against the lamp post and we played indoors until well after dark. When I was called home, I came out and there was a purple bicycle parked where my bike was left! I cried all the way home, thinking my bike was stolen. My dad and I walked back down there and he started laughing. We had written my name on the back of the saddle. There it was! We took the bike home under the normal lights and it was red again. If dad were still alive, he would still be laughing at me for this. Yep! I grew up to be a video engineer. I work with all colors now and don't get fooled any more. As much or as often. 😁

[@karlkarlson3502]

Lol 😆

[@cosmic_cupcake]

I kinda miss these. I feel like they were much better for nigh vision than the modern LEDs. They were also leagues better for good night sleep when you have a street lamp near your window.

[@bertiesworld]

We have LED street lights but they go out at midnight and if it is still dark, come back on at 6am. No good for me though, I go out at 5am ... in the dark.

[@galaxys8-ml]

@@bertiesworld If LED were so cheap and efficient as the claim they wouldn't do that.

[@kostyakozko1]

Couple years before COVID I was at exhibition called "Monochromatic room" (or smth like that), where my skin looked grey in monochromatic yellow light. Now I understand how it worked, thank you.

[@jonnyreverb]

It would be interesting to see it mixed with a monochromatic blue source (like a 440nm laser light) to make white that doesn't show most colors.

[@ABaumstumpf]

Another benefit of Sodium light is that the near monochromatic nature of it makes it easier to perceive motion, and it is better for night-vision in general (they are still used on some ships where people need to go outside into the pitch black night as to not hinder their nightvision so much). As for the lamps i am using: an oooold halogen desk-lamp (nearing 30 years of daily use), some (bad) GU10 LEDs with just barely 60lm/W, and ... a 180lm/W 9.5W lamp for when i need some light for crafting :)

[@luminousfractal420]

you should be alright now. the new style cob leds. ive got one glass bulb with those in thats got a really nice streetlighty tone to it. i think were passed the dark ages of leds 😂

[@newpivot1]

The sparkle of fresh snow under these look majestic.

[@lakloplak]

I remember having to work in the Fujifilm factory and all they had was Yellow lights. Such a vibe.

[@viktorakhmedov3442]

My childhood supermarket had these in the parking lot in really sleek 4-way pole-mounted fixtures. It was built in 1974 and was an ultra-modern, state-of-the-art hypermarket store and the lights really added to the mood. They built several stores in those few years and all the others had high (100') mast lighting poles like they have on freeways with conventional metal halide or HPS fixtures.

[@tylerkinley268]

All my nocturnal memories of the 90s are filtered through that light. How many late nights spent wandering beneath those lamps? Nostalgia for a lightbulb.

[@photonik-luminescence]

I'm happy to see the low pressure sodium light as it's one of the coolest light bulbs. As an light bulb collector and science interested, this video was absolutely great, especially outlining the monochromatic light. Also, if anyone wants to do this without purchasing the light bulb and fixture, you can use baking soda or a solution of salt in napkin over a candle to emit some of the sodium light.

[@MadScientist267]

An interesting experiment involves doing that *in* the LPS light. The so called "black flame" experiment.

[@mernokimuvek]

If you underpower a HPS (SON) lamp the sodium vapor pressure will be lower and the light output will be similar to a SOX lamp. At even lower power it emits a bluish white light from the xenon-mercury discharge and the aluminium oxide arc tube phosphoresces in deep blue for several seonds after turing it off. But you need a few 10 mA of current like a neon sign transformer for that.

[@photonik-luminescence]

@@mernokimuvek I potentially know how to conduct this experiment. I wil preheat it and then power it with a tesla coil. It works as i tested it, but i forgot to do the black flame experiment while at it 😂

[@mernokimuvek]

@@photonik-luminescence You can do a black lamp experiment if you have 2 SOX lamps. Turn one off and the arc tube will look black if you try to look at the still on SOX lamp through it.

[@mernokimuvek]

@@photonik-luminescence SON and SOX lamps have an evacuated outer bulb and can produce X-rays with a Tesla coil. Be careful with that. Some metal halide lamps and lower power (50 W) high pressure mercury vapor lamps also have an evacuated outer bulb.

[@MrDubje]

Hehe. I have the same fixture and brand-new lightbulb in it. If you use it for a longer time as the only (powerful) light source, it messes with your vision. As soon as you return to "normal" light, everything looks green. For anyone wondering, the fixture is called a Philips XGC001 Mini Sox Kombi (I think the Kombi means that it is a fixture with a light-source sold as a set originally).

[@DigBipper188]

I ran up a 200w SLI/H for a few minutes... that sucker had me seeing green for at least half an hour lol

[@MrDubje]

@@DigBipper188 hehe. Yeah, don't run it too long as a single light source. xD

[@mernokimuvek]

Unfortunately Philips stopped making SOX lamps in 2019.

[@MAGGOT_VOMIT]

Those frosted glass rods in those older multi-vapor lamps (lighting warehouses) make great knife sharpeners.

[@DigBipper188]

Alumina ceramic can make a damn good fine abrasive :)

[@mernokimuvek]

Do you mean aluminium oxide arc tube from HPS or CHM lamps? Absolutely no reason to destroy even a worn lamps, they are great for Tesla coil experiments.

[@sigmanation6957]

​@@mernokimuvek Looking at these two comments made me think of a New Vegas skill check. Like OP had a high Melee Weapons skill and you spec'd into Science.

[@centurybug]

Sodum lights are such interesting technology. I learned from Technology Connections that the monochromatic light makes them very useful for photographic darkrooms, but I'm not sure what other use they would've had back in the day.

[@DigBipper188]

General street lighting, reprographic and scientific are the 3 main fields sodium vapor lamps have been known to be used in. for general street lighting - The UK implemented a program in the 1970s which saw mass replacement of incandescent and mercury vapor sources with low pressure sodium due to an ongoing energy crisis. Areas around telescopes and observatories favored SOX as well since they can filter the single wavelength of light they produce with ease. In reprographic - You can run low pressure sodium with an IR Filter as a safe light, since film isn't as sensitive to the 589nm wavelength as it is most other wavelengths of light, it means you can work under it without an enhanced risk of spoiling your film as it's developed. and in scientific applications, sodium vapor lamps are used a lot for displaying the photon emissions of elements. There are plenty of spectral lamps for noble gases like Neon, Argon, Krypton, Xenon etc but you can also get spectral lamps for sodium, mercury, potassium and Cesium if you want to see how adding certain elements affects the spectra of a gas discharge.

[@5oclock_Charlie]

Beat the notification, not that KZbin sends them to me on time anyways.. hours or days later.. Always loved the look of the light sodium vapor lamps make.

[@alexdrockhound9497]

But you didnt beat the bots :(

[@5oclock_Charlie]

​@@alexdrockhound9497 nope they are much faster than a sluggish human without their morning coffee lol

[@brainiac75]

Thanks for the very early watch and comment! Yes, while they are not good as work or dinner lights, the way they just illuminate the night (and aren't too hard on our night vision), they are wonderful lights. Beautiful sunset-ish color too!

[@Tybold63]

Fascinating study, I remember well in my youth those yellow traffic lights and how "fun" it was to watch things in the monochromatic way :)

[@otherunicorn]

I remember when the highway was lit by these. All other lamps in the area were dual 20W flouros.

[@mernokimuvek]

In Hungary we had 3x40W and 3x65W fluorescent lamp fixtures. Each tube was powered from a separate phase from the 3 phase supply to eliminate 100 Hz flicker. I think other European countries did this too because unlike in the UK and North America, 3 phase is common in Europe even for small houses.

[@Wenlocktvdx]

Brings back memories of them in London in the 60s and 70s. They were less diffused by fog, cars had sodium yellow foglamps. There were issues too, fire brigade were not happy, as the yellow reflecting on aging window glass could look like flames. Police too as witnesses could not say what colour a car was. And watching the yellow bars when riding in the car with mum and dad.

[@scythelord]

I like sodium lamps. We haven't completely stopped using them. They're still mandated around observatories that I'm aware of.

[@Tassadar4Ever]

What an interesting video! I'm an electrical engineer but the way the information is presented, it kept me rather transfixed and via concepts I had been taught in undergrad classes, so didn't have me wanting to change the video.

[@R.Daneel]

These are the street lights of my childhood. They were everywhere. Even as kids we thought it was cool how dramatically they could change the perceived colour of all your clothes. Apparently a frustration for police, too. A report of a criminal in a black jacket could actually wearing a vibrantly-patterned coat.

[@balsalmalberto8086]

Hmm.. that's a good argument for the use of white leds.. stupid people always ruining it for everyone.

[@andymouse]

Blimey ! I used to like the occasional 'trip' out in the middle of the night. After maybe 50 mushrooms this light is a big deal and evokes huge numbers of awesome memories from my trippy teenage, might have to one of these bulbs !.....cheers.

[@ericlotze7724]

I didn’t realize they were made this small! *I NEED One!* Maybe another project for that person making brand new nixie tubes and such!

[@ericlotze7724]

@daliborfarny Did *the ping* work? Granted plenty busy as is! I need to binge watch your recent videos too :)

[@DigBipper188]

Thorn experimented with making them even smaller than 18w. There exists a few prototype 10w SOX lamps, but getting a hold of them is challenging. They're even rarer than linear SLI/H sodium lamps are

[@mfbfreak]

Better buy them from existing production. DBL Verlichting sells new ones for very reasonable prices (around 30 euro). Sometimes that store also has ballasts and ignitors in stock. You can make do with an 18w fluorescent ballast and starter if you can't find the proper ones.

[@G5Hohn]

I remember seeing these lights in Europe in parking lots and such when I was there in 2004, pre LED. I don’t recall ever seeing them in USA though, our are more orange-looking and you could make out some ranges of color.

[@broshmosh]

Nice to know I am definitely not going insane thinking LED streetlights are dimmer than the old yellow street lights.

[@canadiannomad_once_again]

We used these in our photography dark room, loved the effect. I could imagine an. LED variant could be quite useful in various situations.

[@cajampa]

I miss those street lamps so much. All these new white LED street lamps, have destroyed the night in my city. I used to love watching the stars, now I can't see them at all anymore. And those white LED have been killing an enormous amount of bugs. Every year since they changed them there is less insects in our local nature. They ate attracted and get stuck in the blue spectrum those white LED's have. They even installed them in the lighted up forest trails. It is horrible how much of nature they are damaging. Those amber lights also don't mess with your circadian rhythm. I use red and amber night LED lights, if I need to go up and do something like go to the toilet in the middle of the night.

[@JPK66]

These low sodium lamps are ideal for use near beaches as they do not attract sea turtles. We had to buy specialty single spectrum LED lamps for use on government installations near the beach as a replacement for these lights.

[@alexanderstone9463]

I’m pretty sure there are some Chinese companies that actually still sell these lamps. One company in particular that I know of, Qianshun Lighting, still lists them on their website. Though I don’t suppose their energy efficiency would match the single spectrum LED lamps that you bought.

[@Hannes.Richter]

I love sodium lamps, this yellow hue at night just feels like a dream, like something else

[@SolarCookingGermany]

As teenagers we used to kick out lamp posts for fun, the vibration disrupted the lamps and it took a while before they restarted again 😄

[@DynamicSeq]

Damn.. I remember this..

[@psirvent8]

@@DynamicSeq Same, although it only works on some old low height spherical ones.

[@stevefreshair9366]

I always liked these Sodium-Vapor-Lamps. It was a science experience in every day life. Thank you for this informative Video 👍🏻

[@eliaschnl]

I had no idea LED lamps have improved so much in efficiency in just the last few years! Now I kind of want to buy some...

[@AzrethK9]

Me too, most of my LEDs are like 10 years old, got them when I moved in. With the degradation, it should be easy to get some that are four times efficient. Sadly it doesn't really matter on the energy bill. it will take thousands of hours to break even. I keep replacing them when they die. Still have some old bulbs for rarely used or hot spaces like the attic.

[@MadScientist267]

There's something of an illusion to it tho. The key factor in both brightness and efficiency is how hard they are driven. To get them *bright* means really pushing them, which generates heat, which is a result of the associated loss in efficiency. Hence the grade on the back of the boxes. I'd have to see one of these super efficient units torn down to decide if it is being run optimally. Heat is also one of the big factors in lifespan.

[@eliaschnl]

​@@MadScientist267I have a cheap LED bulb I modified to run on less power. Big Clive did a series of videos where he removes one of the resistors that set the current. The mod significantly reduces the heat produced while keeping the light output reasonable. It works better with brighter bulbs that have more diodes. My cheap IKEA bulb has a value of 96 lm/W while the Philips has 210. So for less power you get more light. I wonder how cool the bulb would stay if you were to reduce the power by 50% to 2 watts.

[@MadScientist267]

@@eliaschnl I drive (my own) lighting LEDs with a buck converter generally and use CVCC to set their current. This allows full dimming control with an absolute current limit to set "full brightness" power. If you want to get fancy, toss a thermistor in with a couple other passives and have it back off when things are heating up. Still a relatively simple driver (compared to PWM) with a much "cleaner" light and it doesn't thermally stress the dies with all the rapid cycling. But the world likes cheap(est possible). 🤷‍♂️ My way? They virtually last forever and run lukewarm at the sweet spot. Yes they can still crank. Do I run them there? No. Use more of them instead.

[@eliaschnl]

@@MadScientist267 That happens to be very similar to the plant light I made my mom. Harvested LED strips from a TV and a buck boost converter. Though mine only adjusts voltage (naughty way to drive LED's!). Still, I run them way below rating so practically no heat.

[@0000Sierra117]

I lived near an observatory as a child and remember these lights fondly. I have a 90w example I scored off ebay a while back, the light output is crazy

[@wrathisme4693]

Film technology buffs and fans of the corridor crew channel will know that this is the exact technology that allowed for perfect 'green screening' in very old movies, shown in the Mary Poppins movie! Green screens have a lot of issues with color spill and transparent materials, but all you need to do is get a transparent material that filters just this very specific spectrum of light and suddenly you have a near 100% flawless cut out to put on anything! This was considered somewhat lost technology previously because the specific crystal device that Disney used for the process was lost, but a film researcher recently recreated it! I don't know if you have the ability to showcase this feature as an experiment, but it's a very cool practical use nonetheless

[@worldtraveler930]

I have seen several videos showing that the low pressure sodium lamps are about to become the Next Greater level of blue screen/green screen in the FX world!!! 🤠👍

[@TheKnaeckebrot]

as a little kid I called those sodium-vapor streetlamps "butterlamps", bc. of their yellow shine and rectangular form (like a block of butter) :D

[@74HC138]

I always thought of them as orange ice lollies (the block shaped ones at least).

[@metern]

The life we lived in before was in a warm lighting. Every lamp and candel light and the furniture colors made life feel warm. Now it's all feels cold, like in a hospital. And i think humans sight isade for that warm yellowish colored light, and not for the bright white light we live in now.

[@metern]

Im my cabin in the mountains. it's light by candle and a fireplace light when the sun goes down. Ans for some reason that makes me feel more relaxed.

[@Ender06]

IIRC Nilered has a short where he lights a fire that's doped with sodium and shines this light on it. The effect is quite neat!

[@MadScientist267]

That's the "black flame" and is due to the idea that something's emission spectrum is the inverse of its absorption spectrum. So rather than appearing to only emit the orange light, it also completely absorbs it. The sodium in the flame is overpowered by the LPS lamp and so appears to be black. Likewise, a shadow is created by the flame if the light is shining through it.

[@sebastiansullivan4770]

​@@MadScientist267 I'm trying to understand this... May sound like a silly question, but why does the lamp not absorb it's own light? If you were to shine a brighter sodium lamp at a less bright sodium lamp, would you get the same absorbing effect?

[@MadScientist267]

@@sebastiansullivan4770 It indeed does. This is one of the principles lasers use to operate. What you see when you look at the discharge of such a lamp is the light that manages to "leak past" the sodium ions and escape. Don't forget that the gas is mostly "nothing", even in the plasma state. The reason the flame appears black in the famous experiment is because the sodium is absorbing more light than it is emitting when the much brighter LPS lamp is present. Normally you just see the other colors that are not absorbed by the flame. This is why if you shine a really bright flashlight at a flame, it seems to disappear. But in the case of the "black flame", the only wavelength present is absorbed by the sodium in the flame itself, and because your eyes have adjusted to the brighter light, the little bit of light the flame produces at that same wavelength is completely swamped by it. If the experiment is done with something like a "heavier" (more carbon) fuel, such as isopropyl alcohol, one can still see the glowing carbon at the top of the flame because it isn't interacting with the LPS light and is still able to outshine it. In methanol/sodium chloride, the flame is completely black.

[@MadScientist267]

@@sebastiansullivan4770 Basically, it does, but more of it escapes. This is one of the principles lasers need to operate.

[@sebastiansullivan4770]

@@MadScientist267 thanks for the answer. I am also wondering would solid sodium also absorb the yellow light and look dark?

[@Xaerorazor0]

Have 4 of these in my workshop. They were so great for the astronomy performed on photography plates and early CCD cameras, still easy to filter sky brightness in the G or v filters where these lamps still show up as a terrestrial source. With the modern switch to LED is causing issues for some observatories closer to cities. More light getting through. If anything, point your lights down to the ground. That’ll help the most.

[@entropyachieved750]

There are some still around, but you can't buy them anymore. They used them a lot in industrys and as an electrician I can tell you it's hard to know what colour wire you have under it. It's also used around observatories because they can filter that light out when making observations.

[@aftbit]

I really like that yellow light. It's so pretty. Maybe it's because it reminds me of dozing during long car trips with my parents.

[@Ancientreapers]

1:27 1977 right after that is when all the street lamps were converted to those Sodium lamps. They've now been converted back to white LED. Which has astronomers rather miffed. It was easier to filter out the sodium light when doing long exposer imaging or time lapse. "Sodium vapor lights emit on a relatively narrow wavelength." Not as easy to filter out the full wavelength of LED white light.

[@brainiac75]

Yep, if you filter out the white LED light, you also filter out the visible light from stars, galaxies etc. I have some glass doped with Nd3+ that should filter out the light from sodium lamps. Will make a video about it at some point.

[@ryanpenrod1859]

These used to be what lit the freeway tunnels around the Seattle area, and as a kid it always made me feel like we were in a launch tunnel preparing to take off into space--like you said, otherworldly.

[@SkepticalCaveman]

That light is great for circadian rhythm at night. White light keeps one awake causing sleep problems.

[@chrisapphillips]

When I was younger most areas used these sodium vapour lamps but there were other areas using mecury vapour lamps with a bluish colour.

[@davidduffy9806]

As an incompetent and try too hard astronomer, these lamps were perfect…. They could be filtered, blocked by a Sodium filter, magic… dark sky!

[@DaveWithMS]

I was at the 1993 Boy Scout National jamboree. They had yellow bug lights everywhere, which were actually sodium vapor lamps and I remember everything at night looked like it was in black and white because of those lamps. It was certainly fun.

[@Unmixable404]

I miss these colors honestly.

[@Sitarow]

The surreal environment that you mentioned in your video on how the light affects your perception of brightness I have felt that as well when I'm doing red light therapy 660 wavelength and 850. When you look at the flame of a candle it looks green.

[@mediocreman6323]

Those sodium-vapor-lamps had only advantage that made them trump absolutely everything else: _Their light penetrated fog_ like nothing else! When you had those above your head (or, rather, your car), it did not matter how foggy it was, you could always see everything. And this is why I miss them.

[@Hobby_Electric]

I have a SOX lamp with 200 Lm/W Few years ago we had one SOX lamp left on the Road. The Light was good for driving and less insects are distracted.

[@thelovertunisia]

In terms of efficiency nothing can beat it even LED. I loved these streetlights. In England they were everywhere. In lifespan they also beat LED.

[@LarsLarsen77]

No, they don't. Nothing beats the lifespan of LED. Induction bulbs come the closest, but these sodium bulbs have metal electrodes that degrade quickly.

[@thelovertunisia]

@@LarsLarsen77 so you say it is only a question of quality? The only type of LED that I Have seen last long are led tubes for replacing CFL but bulbs and especially spots don't last long.

[@carloseriguinha]

​@@LarsLarsen77 Sorry, but this not true. I remember on 90`s those mercury bulbs run for more than a decade better than any Led now in my City. Even compact fluorescent beat by far Led lifespam and lumens maintenance. I remember those first ones made by philips working 24h and any Led didnt 1/4 of that. No one told that to me, I seem that.

[@somebodyelse3004]

I love these lamps for street lights. I looks unreal but also very beautiful and it’s calming.

[@mayotang5543]

for a second i thought it was a new photonic induction episode

[@dancoulson6579]

I was thinking that too. The large 131w SOX lamp briefly shown at the end is what he uses to illuminate his street, in a video.

[@marcfruchtman9473]

I had been tracking Lumens per watt for years but stopped when LEDs hit mass market. It is great to see the efficiency has improved. There was a microwave sulfur technology that seems pretty interesting for a while, but I don't see it around.

[@frigglebiscuit7484]

i swear sodium lamps cut through the dark better. the old one on my street could shine all into my yard. they replaced it with a lead head. it sucks. i cant see anything without getting my eyes blown out by the glare of the led.

[@muhammadeggy2129]

So the humming sound that i heard from street lamps are from these type of lamps, good gracious that's one thing that stuck in my head has been scratched out.

[@kjjosker]

One benefit of these lights and something that I miss is that they provided better visibility in snowstorms.

[@AhanafRusho]

Oh man what did you just bring out!! Haven't seen sodium in decades, also the red light because of low voltage, ahh takes me back! 😌😌😌

[@maxnova9763]

Fun fact: That’s how Disney was able to do green screen effects for Mary Poppins way before the advent of computers. They flooded the set with sodium vapor lights and a one of a kind hand made prism in the camera was splitting exactly that wavelength creating a real time matte on a second roll of film blocking out the actors from the background.

[@Not_SatoruGojo]

True. This way of keying transparency is much more superior rather then green screen. You don't need to tweak any settings and adjustments as you usually do with green screen to make it look better. It instantly gives you perfect transparency, you even can film fluffy hair, glass and bottles of water, and they will look perfectly natural.

[@lhoffmann6537]

Back in the 80s and early 90s, our town square was illuminated by these sodium vapor lamps. Everything was an intense yellow/orange color. When the city changed to new wjite lights, the difference was amazing.

[@aarongreenfield9038]

The difference is those LEDs don't last nowhere near as long, I've noticed the street lamps in my city going bad in as little as a few months some mere weeks, They start to change color or flicker, and about a third of them have gone completely out. Some are strobing like a strobe, some in intervals of about 5 to 10 flashes a second, some around 1 every 2 seconds, and some have turned bright purple. Some where even the bright purple when they first installed them. And on top of all that, a lot of them just stay on 24 hours a day. It's a mess.

[@LRK-GT]

While I'm not at all a fan of LED street/lot lighting... Those issues are mostly* from cost-optimized driving/control circuitry, not the LEDs themselves or even the technology. The old SOX lamps had some 'fun' failure modes too, but nothing like these LED monstrosities. *Beyond poor EMC design causing and receiving interferance... There's also some 'spooky' implementations in some of the LED street lighting: Superfluous-for-function computerization/electronics on-board that complicate reliability and (sometimes) make you want to dawn They Live shades and a Tin Foil hat. 😅

[@aarongreenfield9038]

@@LRK-GT Oh I know the computerization turns the reliability/ functionality to shit, every time theres a Lightning strike or power surge, they go completely crazy and start flickering, going on and off, and changing colors. By that I mean like a rapid 3K to 5K temperature switch back-and-forth, in a seizure inducing manner. And it gets even better, the one across the street from my house While it's doing that, makes an extremely high pitch shrieking sound for about 20 seconds.

[@Mike-de7wv]

NIce video :) I believe these were typically used a lot for street lighting. I guess most are now LEDs for a greater / more rounded colour temperate range. I have fond, if vague memories of being at my nan's council house as a kid (35+ yrs ago), with the yellow sodium street lights illuminating the passageway on the side of the house through the textured glass in the door.. :)

[@Janokins]

I miss the reddish glow of those lights warming up, but I don't miss trying to figure out what colour the bins were when I was taking out the recycling

[@corwinhyatt519]

A couple of cons that I noticed with the newer LED street lamps when they were being installed where I was working and living back a decade ago was how painfully bright the lamps themselves were when in direct view and how little they actually "illuminated" outside of the emitter's direct illumination cone (anything directly within would reflect and be visable for a good distance, anything outside of the illunination cone turned pitch). With the Yellow amber there seems to have been a bit of a bleed (might have been just how wide an angle the lamps were designed to illuminate) that caught more of the surrounding area. I worked night security when the town I was living in did their transition. Night illumination went from a dull yellow glow with a few dark patches in the area to patches of illumination right under the lamps surrounded by huge dark patches. Ya, the yellow glow was worse for color quality, but the better color quality lamps were worse for actually seeing if something was there. The light actually hurting to try and see in didn't help.

[@Marcos-ee7nt]

That's just a property of a brighter light being outside, it has a more apparent contrast as it has nowhere else to bounce but to go straight to the atmosphere.

[@SurnaturalM]

Where I live, they used a giant version of these lamp on the highway. It was weird to see these lamp when they were cold and lighten up with the pinkish hue, and slowly turn to orange when at full brightness.

[@kanalnamn]

I miss driving at highways thru cities lighted with lamps like these. The light were kinda cozy. Yellow and cozy. :)

[@isaaclove1144]

I forget where I saw it but somebody had a demonstration with one of these lamps and a sodium doped flame. The flame appeared to be black because it was absorbing the same wavelength that the light bulb was emitting.

[@cbfrider]

What I liked about the old sodium lights was that the street, though lit like an old sepia photograph, was completely lit and securely lit. What I hate about (most) LED-street lights is that they seem to mainly focus right underneath the lamp, leaving (sometimes really) dark stripes in between. It seems as if there were figures that looked good for the LEDs on paper and the cities bought it, but to my eyes I'd like to have the old street lights back, to have a more spread illumination - even though monochromatic. Because the light was there to safely get from one place to another, not to read a book or work there...

[@luminousfractal420]

your exactly right. that is what happened. jobsworths

[@C4_Corvette_man]

You earned my sub you somehow made light bulbs interesting

[@Cire605]

In Saskatchewan SaskPower used high pressure sodium either 100w 150w 250w or 400w bulbs. Also in sentinel style light fixtures they used mercury vapor. We now use LEDs with a warm white light.

[@jansenart0]

Sodium Lighting is effectively black and orange. 6:00 I remember this phenomenon back when I was a kid playing under the sodium street lamps, noticing that everything seemed to turn black and white.

[@mrpicky1868]

i was in a room with this light as an art installation. everything looked B&W truly unique experience

[@WalterBurton]

Just wanted to say, great sound design, as usual. 👍👍👍

[@vidarkristiansen8989]

I have a sister that is 2,5 years younger than me. I remember when we were small kids back in the seventies, she actually got physically ill (with motion sickness like symptoms) when seeing those orange lights, lighting up places like streets and train stations.

[@CatsMeowPaw]

I remember these lights being used everywhere. I kind of miss the weird light output of sodium lamps, and didn't really notice the change to LEDs as the transition took decades to achieve.

[@hentype]

This light is as warm as nostalgic. It made me remember a particular night drive that might have been buried deep in my memory for years to a corner store with my grandparents and they bought me a popsicle with 3 colors in shape of a rocket.

[@punkdigerati]

You can use the very tight spectral output of these to do really clean keying for videos, they used to do it way back before computer graphics.

[@snik2pl]

In my city, two years ago, there were low-pressure sodium lamps on one street. compared to high-pressure lamps, the light was actually monochromatic. the lamps were in the form of long tubes like fluorescent lamps

[@Spyd77]

When I visited the Guggenheim museum in Bilbao, Spain, they had a room where in the center was another triangular-shaped room hung from the ceiling, no floor, no doors, no windows, but high enough from the floor to crawl into. Inside, the only light source was a sodium vapor lamp, and the contrast from the regular light from outside the triangle-shaped room to the monochromatic light inside was very shocking. I guess we are used to that kind of light when driving on a highway at night, but inside a room is jarring. Cool exhibit.

[@jhsevs]

I really wish I had fog lights on my van made from bulbs like this!

[@Platypus_Warrior]

In Lisbon Portugal, street lights are similar, not sure if it's the same tech but honestly I love it. It really brings a special atmosphere and it doesn't seem dangerous to drive in it.

[@gplustree]

Most (but not all) orange colored lights are high pressure sodium, which emits a bit more different colors of light and has somewhat better color rendering as a result. The HPS lights are still orange, but not that striking deep "pure" orange that can only be produced by low pressure sodium. The HPS lights look a little bit closer to white while still being very orange.

[@mernokimuvek]

@@gplustree CCT is 1700 K for LPS and 2100 K for HPS.

[@granttaylor3697]

I use to install these SOX lamps in large outdoor areas, as they were everywhere back in the 1990's, still like them today, but technology has moves on.

[@kaspervendler1726]

The way that you take into account the light sensitivity of the human eye, when making an analysis on light efficiency is truely remarkeble! High CRI bulbs should have a different energy efficieny scale/label to compensate for this! :D

[@robd1365]

There is something charming about a street still lit with older sodium lighting, our road has historic street lamps so hopefully they will never modify them to the clinical LED fittings used on main routes. They have a high failure rate compared to the older lamps. Living in austerity Britain, the streetlights on side streets go off at midnight because of cost, we are used to it now after 15 years of cost cutting, but the old orange glow of sodium meant safety, and not twisting an ankle on broken pavements

[@BleughBleugh]

Great video, thanks. Loved playing ‘what colour is that car’ back in the 80’s at night :-p