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I was told by 2 dealers, if I changed the interior lights to LED it would invalidate the Warranty. I got the impression if I got the LED bulbs from Kia it may be ok.
 

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It is illegal to change the head lights from halogen to LED.
Source please! An authoritative one if possible.:)

It might be worth noting that factory LED headlights are designed as complete units, and replacing factory halogen headlight bulbs with LED bulb replacements will not necessarily give the same results.
 

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Source please! An authoritative one if possible.:)

It might be worth noting that factory LED headlights are designed as complete units, and replacing factory halogen headlight bulbs with LED bulb replacements will not necessarily give the same results.
This web document updated at 2018 discusses LED headlights about halfway down, with references to various official regulations -
 

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I had wrongfully assumed that provided the LED replacements for headlamps were designed to be road legal (many are specifically marked as NOT being road legal, even ones linked to on speakev forum!), then it would be legal to replace your headlamps with designed-to-be-legal lamps, but not so

https://blog.motoringassist.com/news/fit-led-lighting-car-legally/

"New cars are fitted with LED lamps, which have been tested and pass Whole Vehicle Type Approval. Under British Road Vehicle Lighting Regulations, LEDs are not mentioned, because they were not invented, when the legislation was penned in 1989, meaning that they are not permitted at all"
 

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I do not understand the obsession people have with LED lights. They are too bright sometimes, dangerous for oncoming drivers. How did people survive before LEDs with normal halogen headlights? Surely we should all be dead because they are too dim and dangerous
What I have not seen from any company selling upgrade bulbs is any explanation of the actual change of distance with more powerful lights, for seeing objects further away with the same brightness.
My understanding is that the inverse square law determines the amount of light intensity falling onto an object at a distance.
But the light reflected from this object back to the eye also undergoes the inverse square law.
Consequently if it is desired to see the same object at a greater distance, with the same amount of brightness at the eye as for the first distance, then the required light output from the headlight has to increase by a factor of the 4th power of the ratio of the two distances.

With real numbers: to increase the viewing distance from say 100 metres to 120 metres, for the same visible brightness of an object, the light power in that direction has to be increased by a factor of 1.2 to the power 4, or about 2 times.
This can be achieved by a bulb with higher light emission, or a more directional narrow beam. Either way it has twice the dazzling effect to the oncoming car driver, for only a small increase of apparent range (factor of 1.2) to the driver of the brighter headlight car.
Possibly some drivers might want an even higher range of distant viewing - so for example an increase from 100 metres to 150 metres would require an increase of headlight light output by 5 times, ie a dazzle effect increase of 5 times for just 1.5 times the viewing range increase.
 

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I note that VW say the top spec ID3 has "matrix LED headlights". Not sure exactly what those are. I also wonder what the lower spec versions get.

The lights on my Golf GTE are the best I have had. Look round corners too!
 

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I think your calculations are out. The loss over the distance is a proportion. So if you start at X lumens from the headlight and are down by A% at the target, and then down by B% as the light returns, but then you change the light to Y lumens, you're still down by A% and B%.
 

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I note that VW say the top spec ID3 has "matrix LED headlights". Not sure exactly what those are. I also wonder what the lower spec versions get.
some matrix LED lamps can be adaptive and will change the beam shape according to incoming lights, thus avoiding dazzling other drivers.
 

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I think your calculations are out. The loss over the distance is a proportion. So if you start at X lumens from the headlight and are down by A% at the target, and then down by B% as the light returns, but then you change the light to Y lumens, you're still down by A% and B%.
Well it seems I didn't get that explanation across at all well!
Here's a bit more :
The aim of increasing the headlight power for the greater distance case is to give the same reflected light from the object at the eye, as for the shorter distance with the lower power headlight.

The inverse square law applies for each direction.

An analogous arrangement using electromagnetic radiation is a radar system consisting of a transmitter emitting radiation, which is reflected from a distant target to subsequently be detected by receiving equipment.

For the car, the headlight is the transmitter and the receiving/detection function is performed by the human eye/brain.

Looking at the Wikipedia explanation of 'Radar', about 1/3rd down there is a short section with the title 'Radar range equation'. About 6 lines of text above the following section (Doppler effect) the equation given contains a term in the bottom line of the fourth power of R. This is the composite effect of the forward and return paths each subjected to the inverse square law.

As I explained previously, the fourth power of distance is the basis of the calculation of the required light outputs for the different distances.
 

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some matrix LED lamps can be adaptive and will change the beam shape according to incoming lights, thus avoiding dazzling other drivers.
My e-Kona equipped with halogen headlights has auto dipping when it detects the headlights of an oncoming vehicle. It seems to actuate faster than I can with manual dipping...
 

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I note that VW say the top spec ID3 has "matrix LED headlights". Not sure exactly what those are. I also wonder what the lower spec versions get.
They are absolute magic.

It's hard to explain, but if you imagine they project a grid of light in front of the car. If the car sees another car in one of the grid squares it dims the light there so as not to blind that driver.

That means you have have them on high beam all the time without blinding anyone.

This video explains it:

 

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Well it seems I didn't get that explanation across at all well!
...
As I explained previously, the fourth power of distance is the basis of the calculation of the required light outputs for the different distances.
Ah, I see, I was only thinking of the same distance but different brightness, you're talking the overall losses for combined distance.
 

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My pennyworth on this one.

LED bulbs, the better quality ones, now have a light source so concentrated from a precision location that combined with a projector housing, there is no optical difference with the projected dip beam pattern (other than colour temperature and light output both of which can be shown to be legal for good bulbs).

I compare this situation with the one for bicycles where in law, LED front and rear lights are technically illegal especially flashing but no sane law enforcement agency would press charges.
 

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For anyone seriously interested in the visibility issues associated with night driving, there are some informative web documents that might be worth looking at, discussing the Contrast Sensitivity of the eye which essentially is the important factor for night time vision :

https://www.aoa.org/Documents/optometric-staff/Articles/Contrast-Sensitivity.pdf
An interesting comment near the end is the apparent improvement of contrast sensitivity for people who indulge in a lot of video gaming with grey video content.

Another document, discussing night driving, with specific mention of age effects is this US study document :
 

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I compare this situation with the one for bicycles where in law, LED front and rear lights are technically illegal especially flashing but no sane law enforcement agency would press charges.
Especially as they don’t bother to press charges against the idiots (majority?) who seem to think it’s fine to ride without any lights at all.
 

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Worst place I've ever been for unlit cyclists was/is Paris where it seems to be a badge of honour for the students to be on a bicycle and invisible!
 
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