LED headlights - how much better?

[ghibbett]

Cyder said:

Interesting thread, I've spent the past 2 years working on a new model with both Halogen and LED head lamps so can hopefully answer or clarify a few of the points raised on here.

Lamps freezing
- It's true the LED modules don't give off any (much) heat and therefore lenses don't defrost like they do on halogen lamps. It's a downside for certain with LED's. It is of course possible to direct warmer air around the inside of the lens but that costs money.

Lamps misting
- All LED headlamps that I know of (and have worked on) have a coating applied to the inside of the lens to stop misting. The results of our testing is that the performance is as good as halogen lamps. (It should be for the amount of money the anti-mist coat costs)

Heat management
- As already said, LED's have heat management issues and are sensitive. As a result although the output temperature is low the LED needs big heatsinks (or air cooling) to call the chip

Light output/performance
- LED light is closer to natural light colour than Xenon, as a result the human eye perceives the light to be easier to see with and you can have a lower lumen output for the same visual result (to the human eye) in my experience of long night testing back to back my eyes felt more comfortable following long periods driving LED lamps over Xenon's.
Also LED lamps are normally a bit lighter than xenons because of the huge ballast pack on a xenon lamp so the CO2 boys like the reduction in mass.

Is there much difference in the performance to the average road user? No not really, xenon to LED is much more subtle change in my experience than halogen to Xenon.

ETA

Why do OEM's still offer halogens when they have fancy LED's or xenon available? Simply because it allows them to sell the base spec car cheaper and make more profit while giving the opportunity to upsell the fancy kit for a few extra grand. Substantial differentiation of low to high grades is a big thing in the OEM world.

Edited by Cyder on Friday 12th September 11:33

Good info there. From one Automotive Engineer to another, thanks for sharing

[Cyder]

No problem, it's one of the few things I actually knowa bit about in this industry!

[Carmo99]

5to1 said:

Jon1967x said:

5to1 - with respect, winter tyre performance in terms of grip doesn't deteriorate above 7 deg by any significant amount, the wear however does. A summer tyre on a frozen road is a million times more of a problem than a winter tyre on a summers day. Its just we rarely get frozen roads in towns - as much as anything because steady traffic over a road warms it up.

Edited by Jon1967x on Sunday 14th September 18:50

You're right it was probably misleading the way I wrote it. Its certainly not as bad being on a winter over 7 as it is hooning around on a summer on icy roads. But my understanding is the warmer it gets the more heat is generated in Winter tyres resulting in reduced performance as well as higher wear. Is that not right with the latest gen winter compounds?

As both a qualified engineer and the fact I live in a climate that demands winter tyres , I can state that in low temperatures the performance of winter tyres saves lives. The grip, confidence, braking etc is a factor different. The benefit of summer tyres is less striking. Unless you are pushing it, 95% of the population would be ok on winter tyres all year, they're.noisier, wear faster and have less grip but not dangerous. 2 years ago in Swiitzerland, the snow / cold temps came early. Having changed my tyres early I was drving circles round everything. By contrast my friend in a nice RX8 keeps his winter tyres on all year (he's lazy) and actually enjoys "power sliding" in the hot summer days. The compunds of winter tyres, high silica content and tread allow more flexibility and less vulcanisity in low temps but in higher or summer temps are only 10% or so lower in performance.

[Buzz Lightyear]

Carmo99 said:

As both a qualified engineer and the fact I live in a climate that demands winter tyres , I can state that in low temperatures the performance of winter tyres saves lives. The grip, confidence, braking etc is a factor different. The benefit of summer tyres is less striking. Unless you are pushing it, 95% of the population would be ok on winter tyres all year, they're.noisier, wear faster and have less grip but not dangerous. 2 years ago in Swiitzerland, the snow / cold temps came early. Having changed my tyres early I was drving circles round everything. By contrast my friend in a nice RX8 keeps his winter tyres on all year (he's lazy) and actually enjoys "power sliding" in the hot summer days. The compunds of winter tyres, high silica content and tread allow more flexibility and less vulcanisity in low temps but in higher or summer temps are only 10% or so lower in performance.

Carmo, you ever tried all season tyres?

I bought some winters and put them on. Mainly as I had to go over to Poland in December so needed them for Germany. I since sold the car, and the winter tyres I had for it.

My tyres need doing shortly, and unsure if all season will be enough if it snows and just use them all year round rather than getting a set of summers and a set of winters.

[Carmo99]

Buzz Lightyear said:

Carmo, you ever tried all season tyres?

I bought some winters and put them on. Mainly as I had to go over to Poland in December so needed them for Germany. I since sold the car, and the winter tyres I had for it.

My tyres need doing shortly, and unsure if all season will be enough if it snows and just use them all year round rather than getting a set of summers and a set of winters.

Not personally and here no one uses them. I'm not even sure they're available. Maybe that tells you something.

[moffat]

Just ordered a new 640d and would have loved to have specced LED's as they really do enhance the 6er's Xenons which are looking a little dated now (to be updated mid to late next year).

But.... £1,600 is a joke, and even on a PCP are just divided by the term so BMW do not expect them to provide a higher residual to the car.

The 640d should come standard with LED's

[jack789]

What is worth the small cost is changing the front "parking" lights to LED ones. As easy as changing a bulb, and they look so much better.

Jack

[breadvan]

Just picked up an X3 LCI with LEDs and I must say they are fantastic.

Now, I'm used to LEDs (MB CLS for 18 months) but its the 'active function' rather than the the light output that really makes the latest LEDs so much better than xenons (and imho worth the premium).

If you're not famililar, you-tube 'BMW Active LEDs' and see what I mean, they're great.

[HoHoHo]

breadvan said:

Just picked up an X3 LCI with LEDs and I must say they are fantastic.

Now, I'm used to LEDs (MB CLS for 18 months) but its the 'active function' rather than the the light output that really makes the latest LEDs so much better than xenons (and imho worth the premium).

If you're not famililar, you-tube 'BMW Active LEDs' and see what I mean, they're great.

The active function isn't only LED's. My F10 M5 has Zenon with active lights (as standard) and I agree it's brilliant.

[breadvan]

Bear with me if I'm wrong, but I thought Active (rather than Adaptive) is only possible with LEDs?

It's like permanent highbeam but blanking out approching cars.

Wierd but very clever.

[Cyder]

I believe it is possible on Xenon units, I'm sure I remember a supplier showing us the setup which was like a set of vertical piano keys or fingers between the projector and the bulb which automatically flicked up or down blocking the light in certain areas.

It's not as dainty as an LED system with multiple modules but technically possible and I think used on some vehicles.

[HoHoHo]

The active lights and functionality on my M5 are exactly the same as LED but are using Zenon.

Holes, moving around, slightly dipped, splitting the lights around other vehicles etc.

It was a feature that became standard on the 2014 M5 (and probably M6)

See here [url]Active lights|url[/http://www.youtube.com/watch?v=-dvPZ3H1Vm4]

Quote "First introduced on the new BMW 7 Series (July 2012) as part of the optional Adaptive LED Headlights, this functionality is now also supported with Xenon headlights on all new BMW 3 Series Saloon and Touring models specified with a Visibility package"

And presumably on the 5 series as mine has it.

Edited by HoHoHo on Tuesday 28th October 14:04

[HoHoHo]

Cyder said:

I believe it is possible on Xenon units, I'm sure I remember a supplier showing us the setup which was like a set of vertical piano keys or fingers between the projector and the bulb which automatically flicked up or down blocking the light in certain areas.

It's not as dainty as an LED system with multiple modules but technically possible and I think used on some vehicles.

If that's how it works, the way the lights move around the road, a black hole following the car in front is pretty amazing.

[Cyder]

I don't know if every system works in the same way, I dare say there's a few different ways to make it work but the last time I saw the system that was the way. As you say it's quite incredible and on a test bench I never believed it could possibly work in the real world.

[HoHoHo]

Cyder said:

I don't know if every system works in the same way, I dare say there's a few different ways to make it work but the last time I saw the system that was the way. As you say it's quite incredible and on a test bench I never believed it could possibly work in the real world.

It sure does and it's interesting to see passengers reaction when they see if for the first time!

[Snollygoster]

Just to clear up the difference in headlights for everyone.

There are 3 types of headlights, Halogen, Xenon, and these new LED Headlights (the ones on the i8 are slightly different but won't go there as not had a technical debriefing on them).

Then within those headlights, there are different packages. These are High Beam Assist, Adaptive Headlights, and Selective Beam. Selective Beam isn't actually a tickable option so to speak, but comes with Adaptive Headlights on certain models across the range.

So High Beam Assist is older technology, which can be fitted with either Halogen or Xenon headlights. This simply changed the headlights between high beam and dipped beam. If I'm honest, this isn't the best and a little slow to react.

Adaptive Headlights are the ones which follow the car around the corner, and point where the tyres are facing.

And then there is Selective Beam. As mentioned above, this is added on automatically with Adaptive Headlights (which add HBA as a no cost option anyway). Now this isn't available for some models in the range such as the 1 Series and X1 (think it might be just those two but don't quote me on that). You can get this with either Xenon's or LED's. This is much more advanced than the HBA, and as others have stated this is where the headlights will split when coming up behind a car creating a black box so to speak, and dim one side of the headlights and not the others.

And finally, LED headlights feature adaptive headlights and selective beam as standard. Most of the video's on the stuff are showing the LED lights, but technology is transferable to xenon's.

Hope that helps clear it up. Sadly there are different people who call it different things which makes it a bit unclear. Here's the youtube video of selective beam. It on the LED lights, but the same technology is on most of the xenon models: https://www.youtube.com/watch?v=-dvPZ3H1Vm4



And in regards to the initial question. I've not had a car with LED headlights which I've used day in day and only taken them home on occasions. There is much less of a jump like the one from Halogen to Xenon, but you can defiantly notice they are whiter and brighter. I'm sure if I used it every day, and jumped back into a car with Xenon's it would be a huge step down.

[RichardM5]

Just to air a gripe, the M6 has LED Adaptive headlights but does not have Selective Beam.

[Cyder]

Snollygoster, are you referring solely to BMW lighting alone or LED/Xenon/Halogen in general?

Some of your points may well be correct if referring to BMW lighting but are not correct if we're talking about other vehicle lighting.

For example, High Beam Assist is likely to become mandatory on new vehicles (if they don't have adaptive lighting of course) in the next couple of years.

Also LED doesn't have to be equipped with adaptive lighting. It can function in exactly the same way as Xenon from a projector unit, or even in a halogen style reflector in some cases.

Oh and iirc, the i8 has frickin' laser beams! (I have no idea about how laser headlamps work yet but I'm trying to wangle a visit to find out soon!)

Edited by Cyder on Tuesday 28th October 16:20

[Fox-]

converted lurker said:

Nobody. In the world. Cares about how trick your car headlights look. Its so teenage its tragic.

We get it, you have the halogens and think they are good. Lots of us do care about trick headlights, though.

[Snollygoster]

Cyder said:

Snollygoster, are you referring solely to BMW lighting alone or LED/Xenon/Halogen in general?

Some of your points may well be correct if referring to BMW lighting but are not correct if we're talking about other vehicle lighting.

For example, High Beam Assist is likely to become mandatory on new vehicles (if they don't have adaptive lighting of course) in the next couple of years.

Also LED doesn't have to be equipped with adaptive lighting. It can function in exactly the same way as Xenon from a projector unit, or even in a halogen style reflector in some cases.

Oh and iirc, the i8 has frickin' laser beams! (I have no idea about how laser headlamps work yet but I'm trying to wangle a visit to find out soon!)

Edited by Cyder on Tuesday 28th October 16:20

Referring to BMW only as that's what I'm most clued up on. And I hope to the love of god High Beam Assist doesn't become standard. Coming from a Volkswagen background prior to BMW (and there bad on the 1 Series), but High Beam Assist isn't very good on a lot of cars. It leaves the other blinded for a good few seconds before changing. My mums Golf Cabriolet HBA is shocking. If they are all to a good standard, yes make them mandatory . At the moment though, please don't.

Clearly I don't know my 6 series models too well though. Could have sworn it was on all BMW LED lights.

RichardM5 said:

Just to air a gripe, the M6 has LED Adaptive headlights but does not have Selective Beam.