How many MV bulb manufacturers are left out there? 

How many desktop PC processor manufacturers are left out there ?

There's EYE, GE, Philips, and loads of Chinese ones.
Then there's Intel, AMD, and lots of smaller manufacturers.

Most (all ?) MV are rebranded from a few Chinese manufacturers. But probably more than one, cause the lamps do differ in construction

I brought the desktop processors in intentionally. There are actually none of the smaller manufacturers there anymore. They all moved to processors for portable devices, or moved away from CPU's altogether. There isnt anyone except Intel or AMD. And yet desktop PCs are here and here to stay, in any configuration and quantity you'd like to order, in the face of all the fanboiz that predicted 10 years ago that in 10 years the smartphones will kill off the desktop PC

Aren't the EYE ones made in Japan?

Lumens per watt is pretty meaningless. What counts is how many watts it takes for a light to acceptably illuminate the area. Lumens per watt might be useful when comparing metal halide to high pressure sodium, since they both emit light in all directions and require similar reflectors to direct the light, but the comparison isn't relevant for LED lighting

In my area 400 watt high pressure sodium lamps at 50,000 lumens, at 125 lumens/watt are being replaced by 164 watt LEDs, at 17,000 lumens meaning 103 lumens a watt. Everyone here seems to be saying "LEDs are less efficent". Which is the case for raw light output from the lamp. But what we care about tis foot-candles on the ground. Where it counts on the ground The 164 watt LEDs meet the exact same standards (minimum and average foot-candles and uniformity ratios) that the 400 watt high pressure sodium lamps do.

As far as the original question, there's not sense asking hypotheticals that have zero chance of actually happening. Even before the ban and even before LEDs the market had moved almost completely to metal halide and HPS. If it wasn't so easy to make a mercury ballast with existing tooling and was also compatible with metal halide, we would have seen the end of mercury ballasts (except for maybe cheap yardblasters) before the ban. No company is going to defy the government to start production to sell a few ballasts and fixtures to people here. Can anyone name a single application where mercury vapor is superior to other technologies?

As far as the original question, there's not sense asking hypotheticals that have zero chance of actually happening.

Wait, what was the original question again?

The laws of illumination are linear. That means, that if you make the conditions like Light distribution, Glare, light spectrum and so on equal between 2 use cases which youd like to compare, then you will be able to compare the cases by Lm/W, as everything else wil be linearly proportional to the Lm/W

Ideally we'd like to use optics (i.e. the luminaire) to adapt the output of whatever lamp to the needed use case. If we succeed, then we can compare Lm/W

When the HPS are being replaced to LED (the nights when half the work is done) it is the best time to see how the FC on the Earth surface are by far not equal

Assuming we are not dealing with 1950s crude optics, corrded reflectors or deteriorated Plastic diffusers on the HPS, HID reflector optics are pretty damn efficient. Most of the 50K Lm are getting where we want them, and distributed the way we want them on the Earth surface. There is no possible way in which 17K Lm or even 34K Lm (if 2 LEDs are used to replace 1 HPS) make the same FC as 50K Lm from a luminaire with similar distribution, installed in the same place



Same as we cant allways compare Lm/W, we cant allways compare FC. The rules for FC for each location specify a range, and even then they are only recommendation. It is the lighting designer, who proposes the lighting installation, who have the final say there

And here is, when the wanted FC levels may change along with other preferences. For example, wanting to suffice with lower FC when the light spectrum is easy on the eyes :

70W MH at 5500 Lm (plain old Quartz there, the CMH get some 8000 Lm) vs 100W LED at 9000 Lm for a park luminaire. The MH is dimmer in 1.6x while using only 1.3x less power. Our vision is logarithmic, and the pupil size of our eyes adapts to the light levels, balancing out the difference even more. Therefore, unless the LED and MH are lighting there side by side, we will percieve the real 1.6x Lm difference as much less difference than 1.6x

The comfortable light spectrum of the MH alone (if choosing well the MH), free from BLH and the preceeding eye strain, more than makes up for the difference : We see better when there is less light but light that is good on the eyes, vs. more light of a type that is a source of eye strain

In the end, the better (not necessarily brighter) lit place is the one that uses 80W per lamp vs. 105W per lamp in the other one (approximate power use with the ballast)



The Mercury have its quite specific light spectrum, that not only we lighting crowds like. The Japanese population and the Israeli lighting designers liked it for a reason, right up to recent times when greenies put their efforts to put bad name to it. Its light makes its own ambience in a place unlike any other HID source. Many big parks built well into the 2000s are lit with nothing but few widely spaced 125's and are exactly the sort of place you'd like to go out for a walk at night. Cant say the same about some more modern, brighter lit places

It is a light source where you choose the maintenance schedule, not the lamps. In a similar way to Induction lighting. The lamps dont fail, they only go dimmer. When you deicide you go and replace them all, once in a few years. Very appropriate when you use the services of contractor to come to your site, so you dont have to call him for spot replacements

It is the light source with the absolutely most reliable control gear, of all light sources that use non integrated gear. It is not easily destroyed by bad line voltages, temperature, moisture ingress and so on. It just keeps working while slowly rusting away even in a luminaire with defective sealing

And CMH can have very nice warm colors.

And CMH can have very nice warm colors.

I have experimented with CMH lamps and compared them to incandescents and there really is no noticeable difference unlike LED.

The CMH does render better things of Blue/Violet colors, although its CRI is not higher than the GLS...

The CMH does render better things of Blue/Violet colors, although its CRI is not higher than the GLS...

But CRI isn't the only way to measure color rendering.

The problem with LED is not the technology itself, that's all fine and dandy, but all of the marketing.

I'm sure if diesel trains were invented today there'd be people on message boards saying about how steam trainsare better and diesel trains really aren't more efficient and aren't "real trains" and are just a fad and it's just a marketing lie that they're cheaper and more efficient to run and all the engineers designing them and people buying them are wrong.

Except diesel is less efficient than gasoline for cars.