farmerjones

It's simply not debatable that LED produces a light in a spectrum that the human eye can see better. This simply means, at night, LED headlights illuminate far away objects better the Xenons, leading to objects that are visible with LEDs and would be hidden with HIDs. This is one of the major benefits of LEDs (along tis packaging and spot-focusing). Agricultural and construction equipment have switched to LEDs because they offer better visibility, especially in dusty conditions. I am a real farmer, and my newer tractors with LEDs clearly illuminate things at a distance I can not see with HIDs (we are talking 10+ flood lamps on each machine). Through this real world experience I firmly believe LEDs off no additional eyestrain over HIDs, as I can often operate a machine for 12 hours in the dark with zero entertain from the LED lights. There is a big difference about "facts" and then "real world impact" those facts have. The truth is LED lights are superior to HIDs in every meaningful way in how they function.

Dan in St. Louis

It most certainly is debatable. It depends on the level of illumination. This research, for example, finds that the peak sensitivity is at 555nm, distinctly yellow, except (as the report states) "Only in very rare cases ... under dark adapted conditions" where it is around 490nm--sort of blue-green. Those "dark adapted conditions" are not likely to happen in the presence of street lights, headlights, advertising signs, etc. Similar research reported here suggest that the peak in dark conditions shifts to 507nm, far outside the peak of scotopic vision which has been described as present "on moonless nights."

My reference to blue light causing glare is based on personal experience. The headlamp bulbs with a blue coating popular among some customizers certainly glare more in my own eyes, and probably in those of anyone as cataracts develop. That's "real world impact."

The City of St. Louis is experimenting with LED street lights and has set their preference at a color temperature in the 2800K-3000K range. The higher color temperature LEDS were gathering too many complaints. St. Louis University found the same, and our own neighborhood is also looking switching to LED street lights and will follow suit. That's "real world impact" too.

I have nothing against LEDs in principle. I have designed several pieces of equipment that use them and my allroad has LED headlights. But I can see better with them not because of their color, but because their controllability allows a longer range with a sharper cutoff below the eye level of oncoming traffic. And that's also "real world impact."

salvadorsantana

gooberman

Interesting.

Good find on the video.

adjax

What I want is extra brightness with the high-beams as that's what I need driving mountain/rural roads at night. And I found it here https://www.uzooka.com/. As Nick pointed out in the video, the LEDS are notably brighter than xenons on low-beams, but LEDs are basically equal or slightly worse on high-beams compared to the bi-xenons, as the LEDs are crippled in the US due to silly regulations.

Mike60564

I have a service loaner today with the Xenon headlights. I have to say the LEDs are notably superior. Better coverage and seem brighter-- that may be partly color temperature.

The base projectors are not as good as the projector headlights in my Acuras.

KevinB656

He mentioned in the video that he got more out of the LEDs in his BMW when he coded it. I wonder if we could code our A4s to get more? Paging Mitchfin!

farmerjones

I don't think the "average peek output" on xenons may really tell the story..... Xenons have a lot more "hot spots" because it's 1 centered bulb in the lens, so certain areas outside of the immediate road ahead are not receiving nearly as much light as the road way. The average light output may be higher than LEDs but it's not evenly distributed at all. The LEDs, while offering a highly-focused beam straight ahead, continues to offer a much broader and evenly distributed pattern. So if HIDs offer 75% of their output in a very narrow forward beam and LED's offer 75% out there output over a wide swath in front of you, then while technically the lumen output of LEDs is lower the reality is it's offering a much greater usable output in real life. And the color of the light plays a part in how your eyes view objects at the edge of the light output as well (in the LEDs favor).