Car headlights all cool white?

mrsteel

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Is there a reason it seems every car used cool white LEDs along with the "projector" style optics, that in my opinion look cheap with a blue and blue outline around them? Is there a reason they couldn't use a standard/orange-peel reflector and neutral white/high CRI LED's?

Any info on this is greatly appreciated!
 

idleprocess

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Is there a reason it seems every car used cool white LEDs along with the "projector" style optics, that in my opinion look cheap with a blue and blue outline around them? Is there a reason they couldn't use a standard/orange-peel reflector and neutral white/high CRI LED's?

Any info on this is greatly appreciated!
Cooler tints due to availability and consumer perception.

Higher CCT LEDs are readily available with some of the best performance - in terms of lumens per watt - at low prices. Every OEM is engineering to a cost and wants continuous availability.

Some thirty years on from the introduction of HID to the market, there is still a demand for "whiter" headlights. This is not surprising since HID - and now LED - are quite distinct from ~2700K halogen at the ~4200K that HID largely settled on and the >5000K that LED generally exhibits. You see this in the aftermarket all the time.

Until there's significant movement on both fronts, I don't expect automotive LED headlights to adopt ≤ 4000K CCTs anytime soon. LED headlights are also often a premium - either by package or trim - so there's little incentive for the OEMs to de-excoticize them.

I gather that projectors are preferred for similar reasons. It's far easier to control light distribution with a projector system as well as offer high/low from a single fixture using a drop shield like HID has done for decades without the compromises of dual-filament bulbs. Projectors are also more sought after by the market than reflectors, possibly due to a façade of exoticism; even vehicles with halogen lights are often equipped with projectors.
 
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ampdude

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I'm surprised they're even allowed by the DOT other than corporate greed and by them being cheaper to make than 4200K HIDs. They look terrible, they blind everyone in front of you, and they don't work that good in rain or other conditions. There's a reason fog lamps are YELLOW.
 

idleprocess

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I'm surprised they're even allowed by the DOT
Love them or hate them, OEM LED headlights in the US fall within the parameters of FMVSS 108.

Aftermarket offerings - i.e. HID 'kits', 'PnP' LED bulbs, and using LED pods/lightbars as headlights - almost universally don't comply with regulations. Some can get close-ish - well-executed HID projector retrofits, high-quality LED bulbs that do their best to replicate halogen filament geometry - but these are a very small minority of the market.
cheaper to make than 4200K HIDs
HID is quite the expense with its high-voltage ballasts and bulbs that must withstand high temperatures and multiple atmospheres of pressure. LED is indeed cheaper by compare using commodity low-voltage DC components that run at more ordinary semiconductor temperatures.
They look terrible
Regardless of how you or I feel about it, the market seems to disagree.
they blind everyone in front of you
This has been a complaint since the dawn of HID projector headlights and has continued unabated with LED projectors. Sharp cutoff + color fringing can indeed be annoying. Correcting headlight aim can go a considerable ways towards correcting this issue; however it cannot address some problems such as the market's love for needlessly-tall 'lifestyle' trucks that effectively never need the ground clearance they ship from the factory with.
 

jtr1962

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I'm surprised they're even allowed by the DOT other than corporate greed and by them being cheaper to make than 4200K HIDs. They look terrible, they blind everyone in front of you, and they don't work that good in rain or other conditions. There's a reason fog lamps are YELLOW.
Whiter light (up to a point anyway) helps with contrast and also peripheral vision. Note I said "up to a point". That point is roughly 4500K to 5000K. Same line of thought applies to streetlighting. Probably 4500K is optimal. No need for anything "bluer" than that except for the fact some people think it looks "kewl".
 

ampdude

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Love them or hate them, OEM LED headlights in the US fall within the parameters of FMVSS 108.

Aftermarket offerings - i.e. HID 'kits', 'PnP' LED bulbs, and using LED pods/lightbars as headlights - almost universally don't comply with regulations. Some can get close-ish - well-executed HID projector retrofits, high-quality LED bulbs that do their best to replicate halogen filament geometry - but these are a very small minority of the market.

HID is quite the expense with its high-voltage ballasts and bulbs that must withstand high temperatures and multiple atmospheres of pressure. LED is indeed cheaper by compare using commodity low-voltage DC components that run at more ordinary semiconductor temperatures.

Regardless of how you or I feel about it, the market seems to disagree.

This has been a complaint since the dawn of HID projector headlights and has continued unabated with LED projectors. Sharp cutoff + color fringing can indeed be annoying. Correcting headlight aim can go a considerable ways towards correcting this issue; however it cannot address some problems such as the market's love for needlessly-tall 'lifestyle' trucks that effectively never need the ground clearance they ship from the factory with.

You haven't convinced me that my opinion is incorrect, but good points and observations! :)
 

ampdude

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Whiter light (up to a point anyway) helps with contrast and also peripheral vision. Note I said "up to a point". That point is roughly 4500K to 5000K. Same line of thought applies to streetlighting. Probably 4500K is optimal. No need for anything "bluer" than that except for the fact some people think it looks "kewl".

To me 3500K is about where it's at for LED's. Everything in a higher spectrum is just noise to me. Strangely I have found some 5000K LED's that I have liked the output of. Not sure why. To each their own.
 

jtr1962

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To me 3500K is about where it's at for LED's. Everything in a higher spectrum is just noise to me. Strangely I have found some 5000K LED's that I have liked the output of. Not sure why. To each their own.
Yes, but you seem to be talking more about aesthetic preference, as opposed to what enables your vision to function optimally. Plenty of people, for example, still prefer to light their homes with 2700K or 3000K, even those choices are awful for actually seeing well. By well I mean with good contrast. Even those people might opt for 5000K for task lighting where the ability to see is more important than aesthetics. Since headlights and streetlights are solely for task lighting, it makes sense to go with what produces optimal results, and that's pretty much in the 4000K to 5000K range.

The 5000K LEDs you liked the output of may well have been high CRI. Even when talking aesthetic preferences, CRI often matters. For example, I hear about people preferring lower CCT lights because they show reds and yellows better. But that's only true if you're comparing CRI 70 or 80 lights. CRI 95 LEDs, even 5000K ones, bring out warmer colors nicely, plus their overall color balance resembles sunlight. At this point I tend to stick solely with CRI 90 or better. No good reason not to given that they're readily available, and only a little less efficient than CRI 80.

Another weird factoid I've noticed is that you can make do with lower illumination levels in terms of lux, but have the same apparent brightness, with higher CRI LEDs. So that sort of compensates for their slightly lower efficiency.
 

ampdude

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I think it was only because the 5000K LED's I had on hand (I think it was a couple of SST's in Convoys) were brighter and threw better than the others I had to compare it against. I believe that my vision functions best with a 3500K 95+CRI LED or an incandescant light optimally. I think that 4000K LED's are a bit blue for me. I normally carry an incan as my first or main light. LED's are always my 2nd string backups on my keychain or alternate pocket.
 
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jtr1962

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I think it was only because the 5000K LED's I had on hand (I think it was a couple of SST's in Convoys) were brighter and threw better than the others I had to compare it against. I believe that my vision functions best with a 3500K 95+CRI LED or an incandescant light optimally. I think that 4000K LED's are a bit blue for me. I normally carry an incan as my first or main light. LED's are always my 2nd string backups on my keychain or alternate pocket.
For any color temp higher CRI is always better. There are variances in human vision. Probably the overall average for best vision is around 4500K but I don't doubt that can move perhaps 1000K in either direction for some individuals. Also, as you age your eye lens tend to yellow. That makes the optimal color temperature go up but how much depends upon the person. I never liked yellowish lighting even as a kid. I remember I preferred to do my homework under the fluorescent in the kitchen, as lousy as the CRI of those old school 1970s fluorescents was. When I learned more about lighting from being on CPF, I found 5000K seems to be my sweet spot. Hasn't changed since. I don't think my eye lenses have yellowed much with age or something like 6500K might now seem optimal. In reality, it seemed blue to me as a kid, as still does.
 

LEDphile

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It is worth noting that how "warm" or "cool" a particular CCT is perceived depends on the light level (https://en.wikipedia.org/wiki/Kruithof_curve). A common example here is to compare noon sunlight (about 5500K, several hundred lux) with a 5000K artificial source at much lower light levels. The sunlight usually is perceived as being "neutral" or even "warm", while the artificial source is typically perceived as being "cold" or "blue", even though the CCT is roughly the same.
 

alpg88

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sun light has full spectrum, leds do not, that is why people see difference between sun light, and led light that is about the same cct
 

ampdude

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A well driven tungsten filament seems to put out far better quality light than even a 95 CRI LED of any color temperature, but that's my opinion.

I'd never prefer an LED to a Surefire P60 lamp assembly.
 
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och

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I wish they sold warm white LEDs, I upgraded the headlights on my motorcycle to LEDs, and they are much brighter, but it would be nice if they were around 3000k for that classic cruiser look.
 
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