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by mcny 2349 days ago
Speaking of lights, are there no laws in the US about how bright headlights can be? At the risk of being too dramatic, I have had cars behind mine with their lights so bright I thought they had their high beams on.
5 comments

That's the idiocy in general of modern car design.

A bright-blue headlight of a modern car will actually make everything surrounding the headlights darker. A light which is slightly dimmer and more shifted towards red works much better for your peripheral vision. If you drive in rural areas the difference is very apparent.

Not only that, but street lights seem to be doing that as well.

Cross-walks here are now illuminated along the path with a strong shaped light. But the light is so bright that during night they just blind the observer: the pedestrian looks like ghost in a black background. IMHO this is even more dangerous, I frequently cannot see past the crosswalk, so a pedestrian which is passing behind it is risking much more than before. Go figure.

There are a couple of intersections which I pass frequently where the green light is too bright already during day. During the night, as soon as you get the green light you get blinded, which is _awesome_ since the light is guarding a cross-walk in this case as well. By night you cannot see pedestrians when you have the green.

The police are the biggest offenders when it comes to unnecessarily blinding drivers at night.

The construction companies (who have to pay their own insurance premiums and generally avoid unnecessarily risking injury to people by blinding drivers) have long since toned down the lights they used (there was a short time period where they all had super bright lights because LEDs were new and cool so why not have a 1000W flasher), switched to the non-glaring light plants that use the canvas bags.

Ok I know this is totally off-topic, but recently it indeed seems as if something changed (and I'm in Europe). Either the newer LED (or whatever they use in cars) are brighter, or they are aimed differently (that makes a lot of difference), or the rules loosened, or a combination of those, or something else which I can't figure out. It's not normal to be blinded when looking in your rear mirror, right?

Slightly related, still widely off-topic: lights on bicycles, same problem. I think e.g. Germany has rules for those, but in countries where there aren't and/or there's zero awareness being raised it's sad to see how many people ride around with LED headlights which are way stronger than required and aimed straight ahead instead of down, completely blinding opposite direction traffic including cars. Now on the commute I do I've made it a sport to (friendly) shout to them telling to put their light down and it seems to have effect. But there's still a long way to go.

Headlights got brighter (no new car uses anything like a classic bulb, going for Xenon or LED most of the time) and cars got a lot taller on average (SUVs are more popular than ever) so you're getting more light even when the car is further away behind you. I don't think regulation changed much regarding this.
Also on some of the cars with EU daytime running lamps, they put the LEDs really low, where only fog lights were once permitted (fog lamps were illegal to use when not foggy), presumably firing up or entirely non directional. These are surprisingly good at dazzling, especially when roads are wet. There's a few makes doing this, but a couple of models are particularly problematic.
All EU cars have DRL now. But the LEDs are basically what used to be the marker lights on any headlight (the first step in turning on the headlights). More commonly now they are overlapped with the signal lights so when signaling the LEDs just turn from white to yellow. But they're almost always still in the headlight block. When for some reason a manufacturer decides to put them in the fog lamps they run at reduced intensity. Just like when the fog light turn on towards the side you are cornering to help with more light.
> Speaking of lights, are there no laws in the US about how bright headlights can be?

See also bicyclists.

There is a general saying that there are two types of lighting: those that allow you to see, and those that allow to be seen. In most urban areas with street lamps, one simply needs to be seen. Too many of my fellow pedallers do not seem to understand this distinction, and do not realize that more lumens does not always been better: at some point you're simply blinding people, and they can no longer tell where you are.

A moderately (500 lm?) bright blinking light, with a simple on-off, non-random pattern seems to be best IMHO.

There are laws, but it doesn't mean they are properly enforced.

Chances are that the car behind you had misaligned headlights or some dubious aftermarket modification, like a HID conversion kit.

Most vehicles will be born and die bone stock. The internet greatly over-estimates the number of vehicles that get aftermarket lights (LED dome light replacement bulbs from Autozone notwithstanding).
Badly adjusted headlights are very common though.

You are supposed to adjust them based on the weight distribution, but people tend to use the highest setting, because that's the best for them. But if they have a lot of weight on rear, the beams are too high and can dazzle other drivers.

And sometimes the optics are simply misaligned because of shock, wear, vibration, ... even dirt can change the beam shape and be problematic. This is especially true for HID lamps, which are closer to a point light source and require higher precision optics compared to halogen light bulbs. And because it mostly affect others, these problems tend to go unnoticed by the driver.

There are, but they regulated wattage, not luminosity.

An old crummy incandescent bulb in a 90s civic will produce a lot less light at the same wattage, than a new, super-bright LED.

That's stupid. I think when these laws were made wattage was a good proxy for luminosity. It should be updated.