100,000 Lumen chandelier is like having the sun a few feet above your head

[Michail] doesn’t mess around when it comes to lighting. He built this 100,000 Lumen chandelier to make sure his office is bright during the dreary months. The thought is that it will provide the health benefits of long sunny day. It has been hanging for about a year now, and he slowly came to the realization that it’s several times too bright for indoor use.

We know where he’s coming from though. When it’s dark at 5 pm we want it to be plenty bright inside. He started with an incandescent bulb, then moved through compact fluorescent and halogen bulbs before deciding to undertake the build. What you see above are 150W Metal Halide lamps.  There is some danger to using these without an enclosure. They do emit some UV light and they can explode. So whenever you buy a fixture that uses them there’s a sheet of filtering safety glass sealing up the enclosed sockets. [Michail] decided not to bother with this safety feature, instead depending on the benefits of an electronic ballast. He says these reduce the chances of an explosion sending scorching hot glass shrapnel your way.

As we mentioned earlier, his conclusion is that just one of these bulbs is enough to illuminate his small office.

38 thoughts on “100,000 Lumen chandelier is like having the sun a few feet above your head

    1. There are very different metal halide lamps. These specific lamps are tuned to match sun light as perfect as possible.

      And the light is perfectly white, without any blue or red tint.

    2. The color temperature of a clear sky in daylight is about 15,000K. Daylight is really blue.

      Point being that because of the Purkinje effect, the perception of color changes as the amount of light changes. More light makes it look redder, so the color temperature must go up as well to make it pleasing.

      1. Daylight light sources (Daylight Standard Illuminant or D65) have a correlated color temperature of precisely 6504K. This is quite far from 15000K!

        While there is no “absolute white light”, D65 is usually considered as pure white.

        Among other reasons this is why D65 is used as the white point of the sRGB color space, HDTV, etc.

        Your remark about the Purkinje effect is interesting but is not correct in this context.

        This effect describes the change of sensitivity to blue light between photopic, mesopic and scotopic vision (bright light, dusk and night vision).

        There is no blue light sensitivity variation between two bright lights with different intensity levels.

        1. I think Dax was probably thinking of the Kruithof curve. It’s true that the color temperature which appears most “white” to a human depends very much on its intensity.

          It’s probably got something to do with our evolution to deal with both dim campfires and bright sunlight. The brighter the light is, the higher the color temperature we want it to be. Try turning on an incandescent light (or ~3000K CFL) in a sun-filled room during the day, and it looks terribly yellow. Yet that same light looks very pleasant and comfortable once the sun goes down.

      2. Ben,

        I believe that you are mixing two concepts: Kruithof curve and color adaptation (also called color constancy).

        The incandescent light in your example look yellow during the day because of color adaptation.

        Color adaptation is fascinating. The brain automatically adapts to the dominant light temperature (a bit like the auto white balance on your camera). After a few minutes, a sheet of paper will always look white under any illuminant (tungsten, CFL, sun, shadow, etc).

        You can try that at home:
        – sit in front of your PC monitor or TV a night
        – turn off all light sources in the room
        – decrease the color temperature of your monitor
        – the image will look yellow
        – work or watch TV during 20 minutes
        – the image will look normal
        – restore monitor temperature to 6500K
        – the original image now looks blue!

        This is why one cannot define an absolute white. Because of human vision color adaption, white is always relative to the main illuminant.

        This is also why color spaces are always defined relative to a white point.

        The Kruithof curve defines what is the human preference in terms of color temperature relative to light intensity. This is a different concept. The Kruithof curve is actually closely related to the Purkinje effect.

  1. Lumen is not a noun so you can say ” 100 000 lumens”
    He shouldn’t mess with the bulb without an UV screen. I did had light sunburns on my face before while tweaking my DIY video projector (granted it was a 400W HID) and it’s really bad for your eyes.

    1. In general metal halide lamps should not be used without UV screen. But these specific lamps have integrated UV filter.

    2. If Lumen is not a noun, how exactly are you expected to use it? You’re saying that every lightbulb sold with the new mandatory FTC labeling is using the word incorrectly?

      No, I think it’s much more likely that you have a loud opinion but no idea what a lumen actually is.

      1. Ok, my english was wrong for the ” noun”… I should have said ” not a Name ” but, actualy, the plural applies to Watt to so I guess plural applies all the time.

        Anyway, lumen has a plural and it should be seen in the title.

        1. No, “a 100,000 lumen lamp” is absolutely correct. “The lamp has 100,000 lumens” is also correct.

          I am not a linguist, so I can’t explain it well, but I am 100% confident in my claim about it.

          It’s the same sort of situation as “a 4 airplane formation” vs “that formation has 4 airplanes.” Just because there are more than one of something does not necessarily mean you add an “S;” some other requirements must also be met.

      1. These lamps have spectra starting at 350nm, which is soft UVA. Lamps without integrated UV filter might indeed have some UVB.

  2. I once built a LumenLab projector using a 400watt metal halide bulb. It’s such an intensely bright light that since ditching the projector I haven’t yet found another use for the bulb+ballast.

      1. I always wanted to build one, but by the time I had the time and resources, Lumen Labs had ceased to produce them / sell parts /etc… Never did figure out why they ditched what seemed to be such a successful pursuit.

      2. Wait, are we talking about the same LumenLab that swindled people out of large chunks of money for CNC mills that they never actually delivered, then tried to run a scam Kickstarter project for a hexcopter using random images off the net? Because if so, that’s probably why they shut down.

    1. Hehe, 1000W Xenon is probably emitting same amount of light (as they are also very efficient), but I believe my implementation is safer for indoor use :-)

  3. Am I the only person who thought “GROW ROOM” when I saw the picture in this post?

    750W of light… just make sure you don’t leave it on for 12 hours, then off for 12, then on… otherwise you might have a sheriff at your door.

    SERIOUSLY SIR ITS FOR MY DEPRESSION ;-)

  4. Wow, I use smaller lamps, 35W CDM-T. They are really bright, 35W (say, 40W incl. electronic ballast) is equivalent of 180W halogen lamp, which is bright enough for me.
    I use 4200K lamp in my workshop, and 3000K lamp in the hall. Actually 3000K is indistinguishable from 180W halogen.

    Metal-halide FTW!

  5. AHH, MY EYES!!!! Anyway he says on his page that he had to put up some aluminium foil (see picture) to avoid looking directly at the lights, since he has a white celling he should just put a reflector under and around the light and just use the light from the reflection the celling, unless of course his “plants” need more direct light.

  6. For pot or people the light-lights should be spread out, not in a cluster. Corners and around would be better for office, not center.
    I want an led light to be dimmable in the following way. At lowest level it is a warm glow, up and it flattens out at highest level it to goes daylight. As perfect as it could get! Romantic, normal, vitalizing.

    1. I want that, too: All the advantages of dimmed halogens, plus higher-temperature daylight, with one simple knob and a lot less heat.

      It seems to me that it is within the realm of a very cheap microcontroller to do this. But meh, the market would never support such a contraption.

  7. Can you also maintain your tan over the winter with this setup?

    And yes like most everyone else I thought “mini pot farm” too. smokin it does keep the depression away, medicinal use only of course!

  8. I have a 70w metal halide a meter and half over my head, as it turns on the first 2 minutes it produces a beautifull slightly greenish light wich when totally on turns into an ordinary white little yellow, friend of mine told me you can change the spectrum by changing a bit the voltage into the ballast, the thing is the light is a little “hard” and gives hard shades, I should wrap it on some white glass.

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