Is it time to ban LED Headlights

area51 said:
Reason why can't see with LED lights is to do with how our eyes work as our sight works in warmer specturm sub 5k while many led are in the plus 6k
Led lights cut the 3 dimensional vision so loose depth so when looking at things they often look more flatter so struggle to see detail
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This is why my mountain bike LED lights are green, white makes everything look flat.
 
area51 said:
Reason why can't see with LED lights is to do with how our eyes work as our sight works in warmer specturm sub 5k while many led are in the plus 6k
Led lights cut the 3 dimensional vision so loose depth so when looking at things they often look more flatter so struggle to see detail
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Just, what? Do you know ANYTHING about light and how our eyes work? I doubt it from reading this drivel!

Our eyes have evolved to work best in daylight - correlated colour temperature very roughly 6500K, but this depends on your location, time of year, time of day, etc. Our eyes also have a peak sensitivity of around 555nm (bang in the middle of the green part of the spectrum). Generally, colder white LED sources have more green (relatively speaking) than warmer white LED sources, so their luminous efficacy (a measure weighted on peak human eye sensitivity) is higher.

Colder whites, particularly those with phosphors designed for peak luminous efficacy, also tend to have poorer colour rendition, which is one reason things can look "flat" under LED light sources. Go shopping, do things in the shops look "flat"? No, but many shops are using LED now instead of the previously popular HID sources now, but the characteristics of the light sources are completely different from those in your car headlights being focused on accurate colour reproduction rather than maximum efficacy.

White LEDs are also not a broad spectrum light source, although developments by the likes of Seoul Semiconductor, Nichia, Philips, Panasonic, etc. are beginning to change this, whereas natural daylight is a full spectrum source (including a lot of power in wavelengths we cannot see, hence why you get sun-burnt if out in the sun too long). This also has a huge impact on how we perceive colour and to a degree depth.

Then you have other factors important for artificial lighting: scotopic vision (https://en.wikipedia.org/wiki/Scotopic_vision), photopic vision (https://en.wikipedia.org/wiki/Photopic_vision), Mesopic vision (https://en.wikipedia.org/wiki/Mesopic_vision), S/P ratio (important for street lighting calculations, especially with LED sources).

You may find it more comfortable to have <5K CCT LED lights, but this is only because we are accustomed to much warmer artificial light sources, e.g. candle around 1800K, incandescent lamps around typically around 2700K, halogen lamps around 3000K.

Please, do some research about a topic before you post such nonsense.
 
robj20 said:
So some truth to the marketing of my green LED bike lights.
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I don't know what the marketing says, but in theory the efficiency (lumens/watt) should be high because it's green, so the amount of light for the power consumption will be higher than white, and therefore the battery pack can be smaller and lighter for a given run period. Typically a "true green" LED is normally around 525nm, although you can buy LEDs at pretty much any dominant or peak wavelength, so whether it is as efficient as it could be (purely from a colour perspective) is unknown. You won't however, be easily able to distinguish different colours under this light source. Whilst this may be unimportant for a very niche application such as this, it's absolutely important for general illumination, and is the key behind why white light street lights can illuminate areas to a lower light level then permissible with traditional sodium lighting (this is where S/P ratio comes in), as a driver's ability to see (by which I mean identify potential hazards) is greatly improved with a white light source compared to a narrow frequency light source.
 
ttaskmaster said:
Supposedly some cyclists find white LEDs reflect off surfaces to teh point where they create a halo effect for the rider. Green LEDs are meant to reduce this effect and let you see more clearly... Dunno how green they are, whether it's a tint or full-on green, but it's possibly illegal...

http://www.legislation.gov.uk/uksi/1989/1796/regulation/11/made:
No vehicle shall be fitted with a lamp which is capable of showing any light to the rear, other than a red light, except–
"green light and white light from a chequered domed lamp fitted to an ambulance control vehicle and intended for use at the scene of an emergency"
"green light from a warning beacon fitted to a vehicle used by a medical practitioner registered by the General Medical Council (whether with full, provisional or limited registration)"

I believe headlights must always be white or yellow.
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Illegal for road yes, my whole bike technically is, no reflectors, no rear light.
Only for mountain biking.
 
Been loving the xenons on my new Focus Tit X - they're the adaptive ones so the beam pattern changes shape, turns into the corners etc. I've noticed they aren't quite as white nor is the cutoff as well-defined as other cars I've driven alongside that have "fixed" xenons but they're still a million better than the halogens I had in the Fiesta I just got rid of.

I can also choose the traffic direction/side in the dash menu, so if I switch to right traffic for Europe, the beam pattern is reversed with the kickup to the right instead of the left like we have over here. Very handy and means I don't have to faff when going to Europe.
 
ultralaser said:
The problem with the adaptive ones, they sound great, but basically they blind oncoming cars then a split second later correct themselves. Not sure that's ideal.
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How do they blind the oncoming cars? The beam pattern is completely flat and lowered slightly at <50km/h, then reverts to a "normal" pattern with a kick up to the left as you get faster. It possibly raises a little at motorway speed, but other than that it's just normal - self-levelling, just bends to the left/right as you add steering lock, it's not constantly raising and lowering as it senses cars. I mean, it has auto highbeam but that's a very noticeable switch to full beam, as it has only one bulb so you see the light "rise" as it switches to high beam.
 
squerble said:
How do they blind the oncoming cars? The beam pattern is completely flat and lowered slightly at <50km/h, then reverts to a "normal" pattern with a kick up to the left as you get faster. It possibly raises a little at motorway speed, but other than that it's just normal - self-levelling, just bends to the left/right as you add steering lock, it's not constantly raising and lowering as it senses cars. I mean, it has auto highbeam but that's a very noticeable switch to full beam, as it has only one bulb so you see the light "rise" as it switches to high beam.
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I think he is confused with automatic high beam
 
I notice this so much at the moment. Especially as more and more people buy SUVs or other high-riding vehicles. I basically get dazzled every time I go out for a drive in the dark.

I do wonder if the modern headlights will be regulated with a certain peak brightness.
 
I was thinking about this thread a few times during recent evening commutes. It’s crazy this still hasn’t been regulated, it’s dazzling every time, especially in a low sporty car. I take issue with auto beams too, coming round a corner there’s always a delay in them switching off. Combined with people who just leave their beams on, it’s just downright dangerous. There’s been a couple of times where I’ve been unable to see the road and just have to hope for the best for a few moments.
 
Stu999 said:
@CaptainRAVE - A few of them I have genuinely wondered if they just have their full beams on, it’s been that bright.
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CaptainRAVE said:
It’s impossible to tell sometimes. They are as bright as the non-led beams used to be.
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In my old Insignia, and Signum before that, the main beam and dipped were the same bulb - all that changed was a plate covering half of it was opened so the whole lens was producing light and not just half of it.

I never bothered with auto-dimming on those as it was just too slow, and it’s still not quite good enough on my current 66 plate E-Class. With both of these though I generally found the dipped beam was good enough on its own, xenon or LED.
 
CaptainRAVE said:
I was thinking about this thread a few times during recent evening commutes. It’s crazy this still hasn’t been regulated, it’s dazzling every time, especially in a low sporty car. I take issue with auto beams too, coming round a corner there’s always a delay in them switching off. Combined with people who just leave their beams on, it’s just downright dangerous. There’s been a couple of times where I’ve been unable to see the road and just have to hope for the best for a few moments.
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Get this all the time when I'm out in the s2000. It's crazy. And it's always the new cars.
 
Yea I didn't like driving the Elise in the dark because everything dazzles with it being so low. SUV monstrosities up your arse with LED lights are the worst. But you can angle the mirror to reflect back at them so they stay away :D

Auto dimming is too slow and sometimes misses things. When someone comes around a sharp bend you always get a blast in the face before it decides to react. It's obvious who is using it.
 
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I'm surprised at how fast the headlights dip in my wife's fiesta, it is almost instant. I'm finding the suvs/vans to be the worst but I'm not sure why as id have thought there would be some regulation to align the lights lower as the headlights in those things must be at the same height as normal car rear view mirrors. I honestly don't know how I'd manage without auto dipping rear view or mirrors. I'm only going of a hazy memory of watching my 911 being mother and the guy slid this machine to check they were right, but obviously they were about a foot lower than the suv/van brigade so not sure if the equipment does both.
 
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