More retail businesses using CMH than LED

I have begun to notice ceramic metal halide (CMH) spotlight fixtures appearing more and more in numerous different stores.
(Just to be sure it is CMH, I hold up a compact disc to the light to see the characteristic spectral lines)

There was a clothing store, mostly lit by fluorescents but had a few 3000K CMH spotlights, some shining on merchandise, others over the display counter. There an upscale supermarket. Most of the aisles were lit by fluorescents, but there were CMH built into the ceiling over all the interesting stuff, and surrounding the perimeter aisles with all the fresh things. I think these must have been 3500K. The market also had a much smaller number of little LED spotlamps (high CRI), obviously replacement for halogen, shining over a bread display and at the meat counter. Lastly I saw a floral gift shop and picture frame store had lighting tracks with CMH, but there were a few high CRI LED floods mixed in on these tracks. The CMH and LED were both screwed into fixtures, and were difficult physically to tell apart. I found this interesting because CMH requires much higher voltage power supply than retrofit LED. Perhaps the CMH bulbs were self-ballasted, not sure, not sure how they did it. But the two looked like the same type of lighting.

I have also seen CMH as the main lighting for a jewelry store and fine suit store.

Now, with commercially available LED technology making so many advances, I am wondering why these stores are using CMH. Ceramic metal halide really only became commercially available in the 1990's, a relative late-comer, though available earlier than LED lighting. CMH is not cheap. The bulbs themselves are fairly expensive, but the real expense is the high voltage power supply. Though they use the same size base, one cannot just screw in CMH into a regular socket, it will not work. Retrofit LED floods are now available cheaper than a CMH flood, though of course we are not talking high CRI here.

As for CRI, ceramic metal halide tends to have higher CRI at higher correlated color temperatures. To get the warmer color temperatures, they add sodium salts into the mix, giving a characteristic yellow-orange line prominent in the spectrum. This takes away from CRI a little. 4000K is available with 95CRI, but if one gets 3000K the CRI goes down to 85. Ceramic metal halide is basically a high pressure version of metal halide, a similar comparison can be made between sodium vapor lamps and high pressure sodium lamps. They are more expensive because the inner bulb must be made of fused alumina to withstand the more intense heat. The spectrum from CMH does contain violet light that activates optical brighteners in white clothing. This might be one possible reason stores could prefer CMH over LED (though I doubt it). Philips has developed "CrispWhite" LED technology which basically just adds a 430nm emitter to address this issue for retail.

Now there are unique differences in the spectrum between high CRI LED and CMH, it is not the same quality of light, regardless of given CRI values (CMH generally has better coverage in the cyan and blue part of the spectrum than LED, though normal high CRI LED has better coverage in the warm colors). In terms of exact color rendering and subjective feeling of the light, there are subtle differences, pros and cons to each. But I doubt most businesses buying lighting are taking any of these finer details into consideration.
The traditional wisdom in the lighting world was that LED was too expensive if one needed large amounts of light from each fixture, but today this is no longer true. High power LED lighting fixtures are available and the price has greatly fallen. Perhaps for sporting illumination where huge amounts of light are required, but I cannot see any indoor application where reasonably priced LEDs could not provide enough light. It is possible CMH could also be used in place of halogen, where high quality of light is desired, but where there is an attempt at energy savings. However, this is not what I have observed. None of these businesses which have recently installed CMH had halogen in those places before.

So back to why stores are choosing CMH. I have seen a few stores convert to mostly LED. But not many. There are more stores that have converted a substantial amount of their lighting to CMH than stores that have converted a substantial amount over to LED. I have to think that higher power high CRI LED products have just not become as prevalent in the market place, and that is why CMH is more popular, because it has had more time to establish itself in the market place.


I know most of the responders to this thread are going to claim how much superior LED is over CMH, but could there possibly be some potential advantages of CMH that current LED lighting products in the market place are not providing? CMH is definitely not cheap. If anything, it is more expensive than LED. So why are all these businesses converting to CMH instead of LED ?

What are your opinions about this? Why are businesses going with CMH ?

I've noticed that the places that have converted to full LED have had to add more fixtures in general to equal the previous lighting system, incl cmh.
Also, some stores had complaints from customers that LED tends to be harsher the eyes than cmh, as well as some pwm issues.
I personally prefer the light quality of cmh over LED. Colors seem more natural. I especially notice this in various produce sections of stores.

Anders Hoveland said:

Why are businesses going with CMH ?

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I think your premise is flawed. Or at least without basis.

I've seen plenty of retail stores in the USA (major chains like Meijer and Kohls) switch from CMH to LED in the past few years. CMH's 10k-15k hour life has got to be a major issue relative to properly designed LED fixtures...

In the USA, we have Target department stores. It was shocking to go a newly remodeled store, cosmetic section. In addition to some narrow long tube fluorescents mounted at the top, above MANY multiple subsections were one LED after another aimed downward on product. It was the whitest, brightest display I have ever seen in a store, making other areas seem dim by comparison. Jewelry stores use halogens to brighten things up, but because there was so much white surface surrounding the cosmetics, it was a sight to see (at least for the lumen aware, like us)

FRITZHID said:

Also, some stores had complaints from customers that LED tends to be harsher the eyes than cmh...
I personally prefer the light quality of cmh over LED. Colors seem more natural. I especially notice this in various produce sections of stores.

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I find this to be true also. Which is ironic, because CMH has all that violet/UV light and LED does not (at least standard LED). I think it must be the wider blue coverage that is easier on the eyes, or the presence of longer wavelength blue.

It's a bit of an unusual situation with me. LED seems harsher on my eyes, but I also have a skin/eye sensitivity to lighting sources that emit violet/UV. So actually being in a place with fluorescent or metal halide for too long makes my eyes permanently ache, like snow blindness. I do not have this problem with LED. But if I just walk into a room, LED definitely seems harsher on my eyes for the first 10 minutes. If the room is lit completely by LED, I find myself with a reflex to want to continually blink, a bit hard to visually focus. So it is really a different type of harshness. CMH gives off beautiful light, but because of my rare sensitivity, if I had to be in a room all day, I would have to prefer to choose LED instead.

I can only share my personal observations and experience. I cannot be sure exactly how everyone else perceives these things. Most of the population probably is not aware enough to consciously notice, but I wonder what other lighting enthusiasts think on this subject.

FRITZHID said:

Colors seem more natural. I especially notice this in various produce sections of stores.

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Actually, I have noticed more supermarkets using LED over the fruit section than using CMH. This would seem to make sense, because the important rendering colors for fruit tend to be reds, oranges, and greens, and >92CRI LED can cover these colors better than CMH at lower color temperature. It is also probably because the LEDs are just being used to supplement the light from the fluorescents, not provide the main source of light. If they needed more intense lighting, perhaps they would have used CMH.

When supermarkets do use LED, it usually seems to be the moderately high CRI type (92-95 CRI). Perhaps this is because they are mostly using the LEDs as localized spotlights, so the color quality is a little more important than for the general overhead lighting. And they want the lighting in the fruit section to have enhanced red color rendering.

So there are many stores using some LED fixtures now, but virtually no stores using mostly LED.
I just meant to say that when it comes to generating 30+% of the general lighting in the entire store with something other than fluorescent, more businesses are using CMH.
So if we counted it all up by the wattage or lumens, the thesis of my thread is basically that the average store uses CMH more than LED.

And yet still nobody believed me when I said barely visible UV is part of CRI.

dc38 said:

And yet still nobody believed me when I said barely visible UV is part of CRI.

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I don't believe you either but I could be wrong. :shrug:

I have wondered though whether really deep blue wavelengths add to CRI to any significant degree. I mean is there an observable color rendering difference if the light has 430nm in addition to just a spike at 450nm ?

I happen to be of the opinion that longer blue wavelengths are more pleasant on the eyes, and that the light source only needs some additional 460nm (as the shorter blue wavelength) for saturated blue color rendering. But I might be wrong. (for example, maybe 450nm is better than 460nm)

One thing that I do know through observation is that sunlight contains trace amounts of UV, (duh) and that many colors, no matter how dull, have a certain vibrance when viewed under sunlight. This leads me to believe that many colors have a sort of photophosphoresence under UVish lighting. I do not yet have a good method to test my presumption...but it seems to make sense to me.

dc38 said:

This leads me to believe that many colors have a sort of photophosphoresence under UVish lighting.

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I think it only makes a small difference when optical brighteners are used, or fluorescent dyes.

found this:

One claim occasionally cited as a benefit of fluorescent light sources emulating the UV content of daylight is the enhanced brightness of paper and clothing treated with whitening agents. Fluorescent whitening agents are used to counteract the otherwise yellow appearance of paper and cloth, making them appear whiter and brighter. To assess this claim, NLPIP compared the relative luminance of white paper and of white cloth illuminated alternately by two fluorescent lamps of identical correlated color temperature (CCT), one claiming to emulate the relative UV content of daylight and one without the UV phosphor. By causing the whitening in the cloth or paper to fluoresce, the UV radiation from these lamps should produce higher luminance for the same given illuminance. Indeed, the measured luminance of a white paper sample and of a white cloth sample were 1.7% and 2.3% higher, respectively, when illuminated by the full-spectrum fluorescent lamp with more UV radiation. These effects were also perceptible when alternatively viewed, but any assumed benefits of these relatively small brightness-enhancing effects have never been documented.

(source: http://www.lrc.rpi.edu/programs/nlpip/lightinganswers/fullspectrum/production.asp )


The sensitivity for blue receptors in the human eye is around 420nm. But I think probably the reason why the receptors are so much more sensitive at these short wavelengths is because natural light usually contains much more of the longer blue wavelengths than the shorter ones, it's a natural compensation design. And the rod receptors in the eye (which are the main receptor type that sees black and white, contrast and shape) barely picks up 420nm at all. So I do not think this should be taken to imply that a lot of 420nm is good.
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Anders Hoveland said:

So if we counted it all up by the wattage or lumens, the thesis of my thread is basically that the average store uses CMH more than LED.

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This is a very historical view and almost meaningless. Even using the term CMH is overdoing it. CMH is somewhat new at least in terms of penetration, but like induction fluorescent, its pretty meaningless as it is just a bit of time before its poor efficiency, high cost, and short life get it steamrolled by LED.

CMH penetration in retail is really not that high. It tends towards the high end in clothing, jewelry, etc. that could justify the cost.

MH is used for food displays, meat, produce, etc. but it is not high CRI, but purpose shaped spectrums (think saturated colors) that make the produce look better than it will at home under more neutral lighting.

The most popular CMH is 39 Watts, about 2000-2200 lumens. That is well in the realm of LED with much lower power, much longer life, and now obtaining similar beam angles.


This is all history though. It would be like discussing the success of vinyl in 1987 or DVDs in 2012. No matter how popular at the time, the writing was on the wall and you can be part of the future or watch the past.

Ditto with CMH.



Semiman

SemiMan said:

it is just a bit of time before its poor efficiency, high cost, and short life get it steamrolled by LED.

CMH penetration in retail is really not that high. It tends towards the high end in clothing, jewelry, etc. that could justify the cost.

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The price of CMH bulbs has been falling, as alternative forms of lighting have been gaining popularity (scale of production). The price of LED has been falling at a faster rate, however.

As for lumen/power efficiency, I did some research into this. Fluorescents have a similar range of efficiency to metal halide lamps. In general, fluorescents might have just a little higher efficiency, but other factors make a much bigger difference, as there is a wide variance in efficiencies for both different types of fluorescent lamps, and different types of metal halide lamps. So basically, the type of lamp you buy will determine the efficiency, not whether you choose fluorescent versus metal halide.

Perhaps CMH has better light quality than 85cri or 92cri LED, but what about at 95cri ? Then it really starts to get subjective which one has a better quality of light.
However, the 95cri LEDs have somewhat lower efficiency, only 54 l/w, compared to 66 l/w for CMH (discussing lower wattage bulbs here).

And with the advent of 97cri violet-based LEDs, one really wonders whether CMH will be rendered completely obsolete (at least for the smaller spotlights).

Anders Hoveland said:

The price of CMH bulbs has been falling, as alternative forms of lighting have been gaining popularity (scale of production). The price of LED has been falling at a faster rate, however.

As for lumen/power efficiency, I did some research into this. Fluorescents have a similar range of efficiency to metal halide lamps. In general, fluorescents might have just a little higher efficiency, but other factors make a much bigger difference, as there is a wide variance in efficiencies for both different types of fluorescent lamps, and different types of metal halide lamps. So basically, the type of lamp you buy will determine the efficiency, not whether you choose fluorescent versus metal halide.

Perhaps CMH has better light quality than 85cri or 92cri LED, but what about at 95cri ? Then it really starts to get subjective which one has a better quality of light.
However, the 95cri LEDs have somewhat lower efficiency, only 54 l/w, compared to 66 l/w for CMH (discussing lower wattage bulbs here).

And with the advent of 97cri violet-based LEDs, one really wonders whether CMH will be rendered completely obsolete (at least for the smaller spotlights).

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You are picking one data point for 54 lumens/watt. It is certainly possible to get higher system level efficiencies for LED, not to mention a wider range of CCTs.

Semiman

The 95 CRI LEDs available in the market tend to be a little inherently less efficient, because they utilize red phosphors.
Obviously the type of LED product you buy is likely to make a greater difference in efficiency than whether it is 85cri or 95cri, as there are plenty of other factors affecting efficiency.
The "data point" I was using is the Sylvania Ultra HD at 9.5w. If we increased the wattage some more, the efficiency would rise, but so would the efficiency of a CMH bulb.
I do not know, there might be some 95cri >10w LED products out there with higher efficiency. They might cost more too.

If we are comparing the quality of light from a 3000K 95cri LED and a 3000K CMH, they are both nice, but the quality of light is somewhat different. It is difficult to describe.
For a connoisseur of subtle light differences, they are both good in their own ways. I think the LED does better rendering for saturated reds and lime yellows, but the CMH does better with azure blues and cyan. And in terms of "harshness", they both seem harsh in a little bit of a different way, again hard to describe. The LED light, just a little irritating to focus on, the CMH just a little sore on the eyes after a while. Difficult to say which one has "better" light. If I was absolutely pressed, I would have to say the 95cri LED has just a little bit "better" light at 3000K, but at 4000K, the CMH has better light. But it's not really "better", just a little different— not that 90% of average people would notice a difference anyway.

I just painted a cathedral living room, lighting up each high wall with one $250 1000watt electronic ballast (growlight) 110 lumen (200k candela with reflector) light on a light weight photographer stand (still lighter and more portable than my HomeDepot 1500 halogen). On a standard house hold circuit, I could have easily pulled a second $150 600 watt 80k lumen light on same cord. (600watt bulbs are rare, unsafe with no o rating, and expensive to replace) ... I love my 1000 watt light, but have luke warm like feelings about my 42k lumen 400 watt- it just isn't a 1000 watt light, but is cooler to run and cheaper. I am not sure if I would like the lumen drop if I replaced the $18 o-rated 400watt MH bulb with a $60 320 watt ceramic. I will likely someday invest in the experiment-hoping price and competition increases for ceramic MH bulbs.

My point is: Currently, led really cannot compete with MH. For a bit over $200, I get single point, reflectored 110k lumens (110 lpw 4000 kelvin, 200k candela) light source. Last I checked, $400 for a 300 watt led light at a weak lpw with maybe 30k lumens. I don't see it changing, as most single led are only targeting 4k to 8k lumen output, not 20-40k lumens per emitter as they should. ... Yes, in 2008, leds couldn't really compete with MH in high current headlamps or flashlights; this has dramatically changed. The question, anyone's guess, is when led will overtake fixed CMH. And, will CMH price come down to the the stupid cheap level of regular 400watt bulbs before led over takes MH entirely.

Probably, my true point: While my 400 watt MH lights stirred only intellectual interest in me (after owning HIR 25k lumen 650 watt halogen Tota), I am really still stupidly, irrationally excited (for last 6 months) over my 1000watt MH. I wish they made a 1500 watt one with same form factor.

I also deal with many head maintenance guys. Interestingly, I find talking to them they know nearly zero about lighting. They know what MH, led, etc. is, but know nothing about the specs. I wonder who is choosing their lighting. Is it rep. driven?

Degarb we are mainly talking about 39w high cri MH in this thread.

WRT LED versus MH ... MH is being replaced en mass in the 250 and 400 watt range. Real life out of fixture efficiency is much better. For high use the rapid light loss of MH is a killer.

320w does not need to be ceramic, it could just be electronic ballasted with pulse start.

Main benefit is not initial lumens but mean lumens .

From what I see, CMH is gradually being replaced by LED, mostly the low wattage tubular types used in track lighting. The PARs are still very common though. Perhaps a few years down the road, LED will start replacing them by the masses.

SemiMan said:

Degarb we are mainly talking about 39w high cri MH in this thread.

For high use the rapid light loss of MH is a killer.

320w does not need to be ceramic, it could just be electronic ballasted ulse start.

Main benefit is not initial lumens but mean lumens .

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I am not sure what you mean 320 need not be ceramic. I refer to the 320 philips chm allstart, which is lower lumen than the 400 watt it supposed to replace. There is a remarkable range of initial lumen for a 400 watt, from 33k to 42k. I think 320 cmh allstart. Is in the 24 or 27 k lumen range. This is downward lumen creep, to my thinking.

For me, I won't ever see significant mh. Lumen drop. A few score or hundred hours here or there. If they get chm price down to $20 a bulb, would they be sensible for retail where changing is simple?

http://www.hoveyelectric.com/hovey-...king-Truth-In-The-Life-Of-A-Metal-Halide-Bulb

Also, mh bulbs get way more efficient at and above the 600 watt point. I think it unforetunate that 400 seems that standard mass produced wattage for big box stores, streets, warehouse, lots.


Also, venture lighting, here near solon, ohio has some mh bulb that is not ceramic mh, but supposed to render colors well. But their bulb pricing ain't cheap... I didn't check of these bulbs are domestically made. I thnk there are cfl factories near me...

also, I see venture claiming %80 lumen maintenance. http://www.venturelighting.com/techcenter/lightoutput.html. I haven't reasearched lumen maintenance of my electronic ballast v. Magnetic v. My probe-- how much of the horror l50 graphs are of probe start lamps? Are not electronic ballast something commercially new? Mine claims to be brighter than magnetic, but I wonder if that claim is only because of a better lumen maintenance. Also, my second hand probe metal Halide suffers from usage drop. However, the 400 watt old probe metal halide is quite a bit more impressive than any 500 watt halogen I ever owned, by an order of 3-4.

degarb said:

My point is: Currently, led really cannot compete with MH.

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This used to be true, even just a few years ago, but the price of commercial LED fixtures has greatly fallen since then. For anything under ~50 watts, the price of LED is very comparable to MH, when one includes the cost of the ballast.

SemiMan said:

MH is being replaced en mass in the 250 and 400 watt range.

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Not sure about the "250 and 400 watt range", but definitely true for 70 watt MH fixtures. I am seeing more and more street lights being converted. But not all of them. In fact, at one park they just put in some new light poles with metal halide. The type of LED being most used is lower CRI, has worse color rendering than the new MH lamps being used elsewhere, ironically.

I bought two 150 watt metal halide lamps, hoping that they would be able to paint bathrooms without any heat, but have yet to use them more than once.the reflectors do a very poor job at evenly directing the light, & I am unimpressed with the efficiency in that wattage class. I paid $20 each, but they sell at Grainger's for $700 each. The lux/candela/lumens is less than a $15 halogen worklight. They take up space in storage area along side other worklights I bought and hate: 300/250 watt halogen bulb lights, low end led, florescent work lights, any steel stand work lights.

The bluish LED replacement is a byproduct of dishonest retail and ignorant buyers. Though, arguments are constantly made for scotopic lumens, which semiman repudiates. One may also assume markup on crappy leds is huge.