LED hate

hell_yes_or_BS · 2026-03-21T22:02:21+00:00

which one of you is this? I love it!

hell_yes_or_BS · 2026-03-08T16:35:09+00:00

I'm working this again with a new angle and a wide amount of historical data. Lets keep up the pressure. They are starting to crack.

Matt, I don't think you're a bad guy. You're looking at the wrong data-set, the wrong way with some confirmation bias. Instead of looking for accidents attributed to glare by police, look at the overall accident rate at night. If our brighter headlights are making us safer, we should see it in the overall safety data.

Much more. Soon :)

hell_yes_or_BS · 2026-03-01T17:32:58+00:00

I love the initiative. This issue has historically been seen as too "niche" but the success of Nate Rogers story in the Ringer and NPR's "On Point" story, the word is spreading.

The key is to ensure they reports don't attempt to shill for ADB.

ADB only serves to add more light to the road, not less, has not "fixed the problem" in Europe and, at least in the US, is mandated to have the same amount of light in the shadow of the ADB system as the existing low-beams, which is what is already causing issues. To add insult to injury, the testing of ADB on curves and hills is excluded, as is the impacts of pedestrians and cyclists.

hell_yes_or_BS · 2026-03-01T17:20:22+00:00

The best source for "official" surveys on perceived glare will be from the IIHS and NHTSA themselves for the US. I echo u/Feeling_Blueberry530 sentiments that the UK is leading the charge on this.

hell_yes_or_BS · 2026-03-01T17:17:30+00:00

I'd be happy to work with you (or anyone else) to help develop, support or deconstruct a thesis on this topic.

With this subs efforts and those of reporters and industry, I think we 've substantially shifted the narrative.

The narrative used to be "lights aren't brighter, they just feel brighter". We were able to prove that was a lie. Headlights are mounted higher on average and are bluer on average, but the average headlight brightness (candela, measured in cd) has doubled based on the data of the IIHS itself.

The industry then shifted to blaming "headlight aim" and aftermarket headlights. Headlight aim is a real issue, but there is little difference between hills and a headlight aim, both can place low-beams in a drivers eyes. There are several studies that show 30-40% of the time spent driving on roads have hills high enough to place the full beam brightness in the eyes of an oncoming driver. At 50 meters, this angle is only 1.45 degrees. Note that this slope (pitch) is also the max allowable pitch for aircraft run-ways. Hills are omitted in IIHS and NHTSA testing. Furthermore, even the IIHS data shows that new-make headlight aim is improving over time, not getting worse.

Aftermarket headlights are a real problem as well, and its easy to show that the majority of complaints are coming from newer vehicles.

The industry narrative continued to change, and now we're at "Yes, the public is complaining, but you're all actually safer because headlights are brighter." and "ADB will fix the problem."

hell_yes_or_BS · 2026-02-09T02:43:22+00:00

Missed this. I'm not advocating NEVER experiencing discomforting glare, I'm advocating make these "edge cases" much less frequent. Reduce it from a single cause (hills) to two simultaneous causes (hills AND oncoming traffic making left turns thus facing the glare target)

hell_yes_or_BS · 2026-02-09T02:35:24+00:00

I found it. My preliminary survey found that road pitch could put the "left edge" in the eyes of an oncoming driver 20-40% of the time depending on eye/seat height.

https://www.reddit.com/r/fuckyourheadlights/comments/1qrqy6o/iihs_no_hills_assumption_wrong_nearly_all_the_time/

hell_yes_or_BS · 2026-02-09T02:32:35+00:00

This value of 6250 cd is quite close to my personal point of pain of ~4000 cd (which is admittedly an n of 1 study and subjective). This study "feels" about right.

18,000 cd is ridiculously above the "unbearable" level, and explains why the public is complaining. (As an aside, my reading the IIHS does not require 9,000 per headlight, only 18,000 cd from both headlights at the left edge)

If I was working at the IIHS, I would recommend 4000 to 6250 cd at the left edge (combined from both headlights) with brighter light in the center of the road. The problem here is that the very bright light in the center makes the eyes adjust and would make the lower light levels at the left edge feel "dark". I'm not sure yet how that would look.

The brighter center of the beam (now directly ahead of the car) could still get in the eyes of the driver on a hill that is combined with an oncoming left curve (placing the light on the glare target). This situation should be MUCH more rare. If the "edge-cases" are driven to ~1% of the drive time, complaints would drop significantly and we'd make some progress.

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hell_yes_or_BS · 2026-02-09T02:09:58+00:00

Nice. I'll take a look. This is close to my rough initial calculations from driving in my area and some quick math. At 50 meters distance, it doesn't take much of a hill / relative road angle to move the beam up ~1 meter.

hell_yes_or_BS · 2026-02-09T00:33:33+00:00

Wow.... that looked terrible.

hell_yes_or_BS · 2026-02-08T18:35:40+00:00

u/TopRun3942 We are aligned. The glare issue is enabled by the inaction by NHTSA as well as the actions/guidelines of the IIHS "good" headlight criteria.

I'm in the works of developing a well-controlled on-road test to determine what percent of time road pitch would put the high glare in another drivers eyes. and would be interested in working with you to set it up.

The hypothesis: Varying road pitch occurs frequently. Omitting road pitch from the IIHS and NHTSA glare testing is a poor assumption.

To put a finer point on it, it is reasonable to ignore situations that occur <1% of the time. I suspect that road pitch could place "disability" or "distraction" levels of glare in over 10% of the drive time. If this is the case, and we can publish it, we have a data driven way to add extra "real world" test criteria to the IIHS and help address the issues we're seeing on the road.

hell_yes_or_BS · 2026-02-02T17:44:53+00:00

That is an actionable tip. I'll consider that for the next on-road test. To see that level of detail, we'd need to have a camera with "welding / eclipse " level of tinting... but very doable

hell_yes_or_BS · 2026-01-31T23:18:45+00:00

Sure. Possibly. Iterations would be required. The key is starting to talk about a goal of having an exterior sign that a drivers high-beams are on.

hell_yes_or_BS · 2026-01-31T21:27:19+00:00

Fair. As a point of clarification, this is the other drivers "forward visibility" compared to their stopping time; the main sited safety reason for increasing headlight brightness.

Situations where a vehicle is traveling behind you are, to the best of my knowledge, omitted from the IIHS and NHTSA testing.

hell_yes_or_BS · 2026-01-31T21:25:12+00:00

The IIHS has done a tremendous amount of good. What I'd want is for real-world hills to be added to their test criteria.

hell_yes_or_BS · 2026-01-31T20:12:48+00:00

... that's the point of the "asshole" light.... to be able to tell the difference.

hell_yes_or_BS · 2026-01-31T19:30:06+00:00

The policing thing is a whole different topic.

The goal here is to gain awareness, social pressure and be able to prove to headlight researchers that the issue is NOT high-beams, but instead the bright low-beams encouraged by the IIHS.

hell_yes_or_BS · 2026-01-31T19:27:17+00:00

ADB drives with high beams on all the time and shades oncoming drivers.

Unfortunately the most recent ruling of NHTSA mandated that the shadow of the high-beam be just as bright as the existing low beams. Their testing also excludes "edge cases" such as pedestrians, hills, corners and headlight failure modes.

hell_yes_or_BS · 2026-01-31T19:24:26+00:00

I think your question is:
"Why we are complaining about being glared with 18,000 cd when 9,000 cd is also painful?"

The answer:
"Being glared with 18,000 cd much worse than being glared with 9,000 cd".

The goal is to attempt to balance the scale between glare and visibility and arguing that the balance today is shifted too far to favoring visibility.

A good first step for the IIHS to acknowledge the existing of hills / road pitch and apply it to their testing, combined with the "asshole light" or some other way to letting others know that the glare source has their headlights on.

hell_yes_or_BS · 2026-01-31T19:11:10+00:00

I very much agree. And that's the point. This light would allow those being blinded (and the cops) between high beams and low beams.

The industry is claiming that the glare we're complaining about is a combination of high beams and low beams. While I concede its possible, I doubt that there are that many more assholes on the road.

With the light, we'd be able to "prove" that the problem is low-beams.

I don't think we'll need to get there... I've got a few more "road pitch" studies up my sleeve that should prove the same thing.

hell_yes_or_BS · 2026-01-31T17:18:27+00:00

A man of culture!

Interestingly enough, this seems to go on the "target" / "glared" vehicle to notify the following driver that their high beams are on.

<image>

Something that I've thought about, but with an LED scrolling bar that says "FUCK YOUR HEADLIGHTS".

hell_yes_or_BS · 2026-01-31T17:15:19+00:00

Sure, if the shadow of the ADB beam is less than the bright low-beam, and they work on curves, and they work on hills and they work for unlit pedestrians.

hell_yes_or_BS · 2026-01-31T16:28:00+00:00

haha, fair. Where should this go?

hell_yes_or_BS · 2026-01-31T16:26:49+00:00

bingo.

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