site banner

Friday Fun Thread for October 25, 2024

Be advised: this thread is not for serious in-depth discussion of weighty topics (we have a link for that), this thread is not for anything Culture War related. This thread is for Fun. You got jokes? Share 'em. You got silly questions? Ask 'em.

3
Jump in the discussion.

No email address required.

TIL: According to IIHS (the Insurance Institute for Highway Safety), the stock headlights on many cars are inadequate. For example, the popular Honda Fit hatchback has headlights that are only "marginal" (2 stars out of 4) or "poor" (1 star), depending on trim. (Several different measurements go into the overall rating. Speaking very roughly, though, IIHS wants to see illumination of 5 lux out to a distance of 100 meters, while the Fit's headlights achieved that illumination only out to 72.4 meters.)

Headlight bulbs that are much brighter than stock while still remaining in compliance with laws regarding off-center glare (unlike some LEDs) are available for a few dollars from various sources—e. g., RockAuto. Note that illumination distance increases with the square root of brightness: 1 lux of illumination is 1 lumen of brightness per meter squared. For example, multiplying brightness by 2.3 will multiply illumination distance by only 1.5—but that's enough to bring the Fit up to IIHS's standards (from 72.4 meters to 110 meters).

5 lux out to a distance of 100 meters, while the Fit's headlights achieved that illumination only out to 72.4 meters

How much does it really matter? I personally rarely drive in places where I have 70+ meters of unlighted space in front of me, and I'm not sure how much going from 72 to 100 (or the reverse) going to change things.

I personally rarely drive in places where I have 70+ meters of unlighted space in front of me

I personally drive in such conditions regularly. Two weeks ago, I only narrowly avoided hitting a deer that was calmly standing in the middle of a three-lane, nominally-50-mi/h (actually-60-mi/h) highway, which is what prompted me to investigate this topic in the first place.

5 lux isn't much, and it's mostly relevant in the sense of highlighting retroreflectors (either tape, or animal eyes). If you're really darkness-adapted and under 40 or so, you'll be able to see fuzzy outlines, but not much more: it's not unreasonable as a metric for 'minimum to see an object', but a little optimistic.

At 65 MPH, 100 meters is just over three seconds to react; 70 meters is just over two seconds. How much that matters depends heavily on what you're doing with that time. Two seconds to swerve is pretty generous. Three seconds to brake is not, especially in larger cars: modeling these things is tough and depends on a lot of specifics to the situation, but at best it's the difference between stopping just before impact versus barrelling through at 20+ MPH, and more likely the difference between 10 MPH and 35 MPH at time of impact.

it's mostly relevant in the sense of highlighting retroreflectors

IIHS's rationale document (page 4) states that the intended target of illumination is low-contrast objects, not retroreflective objects.

Huh. I don't like how little citation there is for that being sufficient brightness -- all the cites are just to people using 3 lux as a baseline measurement, and that for instrument sensitivity reasons -- but I guess I don't really have the numbers to say that they're wrong, either.

If you're really darkness-adapted and under 40 or so, you'll be able to see fuzzy outlines, but not much more

This is what annoys me about the push for full self-driving: instead of spending most of the time on AI, I want that [same underlying] sensor technology to start highlighting things (4-legged animals, 2-legged animals) that I can't see yet using the inside of the windshield as a screen. I want to be able to see cars through other cars- it doesn't matter if Truckzilla pulls out too far beside me when I'm trying to make a turn because I can just see if there's something coming directly.

I want technology to help me make better decisions on how I should drive; not to replace me. But I'm one of those weird people who actually likes driving- most people don't, so why would anyone ever develop a system like this?

That would be awesome. We’ve already seen the first wave of augmented senses with proximity radars and, arguably, the backup camera. Stuff like the blind spot indicators. Use those for a bit and it’s unpleasant to go back.

I suspect that display technology is part of this holdup. We’ve certainly tried, and then sort of gave up in the early 2000s. Maybe we’re due for a comeback.

Yeah, that's fair. There's been some work done for automotive HUDs, but there's (not-unreasonable!) concern about anything more serious than simple fixed-location infographics being distracting or vision-obscuring -- bizarrely, meaning that the display tech once existed and now doesn't -- and as a result things like blind spot detection or collision avoidance systems tend to rely on other inputs that tend to fall into the meaningless alert problem or at best just push sensor data directly to the instrument cluster.

anything more serious than simple fixed-location infographics being distracting or vision-obscuring

I think "put screens everywhere" is a clear signal that we don't give a shit any more about what's distracting you behind the wheel. (They obscure your vision due to glare and, if the company is/was obsessed with the color blue at the time, kill your night vision just as surely as the new LED headlights do).

My favorite is the one where you have to click through a full page disclaimer of tiny text about how looking at the screen is dangerous in order to actually get the to the necessary functions that the screen provides.

The thing that drives me up the wall these days is headlights that shine directly into opposing traffic. I don't know what the fuck is going on recently but probably about every tenth car is blinding me at night.

I don't know what the fuck is going on recently

Well, 3 things:

  • Ride heights are much higher than they were 10-15 years ago. "Hatchback with a lift kit", which is what all CUVs fundamentally are, weren't quite as dominant in 2010 as they are now (where you can't buy a non-lifted hatchback). They make sense if you can only own one vehicle though. As a result, the headlights are going to be physically higher up on the vehicle than they otherwise would be. [Aside: people also like these things because being higher up is the only way to regain the visibility that those increasingly-absurd impact ratings costs you; I feel that if you drive sufficiently incompetently as to roll your car at high speed you probably deserve to die relative to the number of pedestrians that lack of visibility kills, and have already put my money where my mouth is on that point.]

  • If you're sitting higher up relative to the road, your headlights will be adjusted up (relative to a lower vehicle) so that you can see further out. Thus, if you're in an CUV, your lights are going to be aimed from the factory such that you'll blind anyone in lower vehicles.

  • Average color temperature of the lights has gone from 2700K to 6500K. This might even be a net negative on how far you can actually see, but it's far brighter up close and fucks up your night vision, which is what actually matters.

At this point I'm a lot more aggressive about not turning my brights off when I see an oncoming car (unless I see the telltale flicker of them turning theirs off, naturally), because if they don't turn them off I'm blind when they pass.

now (where you can't buy a non-lifted hatchback).

Sure you can, it's called a Prius. Or a civic hatchback.

If you're sitting higher up relative to the road, your headlights will be adjusted up (relative to a lower vehicle) so that you can see further out. Thus, if you're in an CUV, your lights are going to be aimed from the factory such that you'll blind anyone in lower vehicles.

This i don't find totally convincing. Why do they need to be adjusted so you can see further out? Obviously you can always aim the headlights higher to see further (and that's what high beams do, partially), but that can't be legal.

At this point I'm a lot more aggressive about not turning my brights off when I see an oncoming car (unless I see the telltale flicker of them turning theirs off, naturally), because if they don't turn them off I'm blind when they pass.

Why are you driving with your brights on?

Why are you driving with your brights on?

Because that is what they are for? You use them at night, when there aren't any other cars traveling the same way, and when there isn't any oncoming traffic. [I don't live in NYC, where there are so many streetlights that night driving would be possible without any headlights at all.]

Why do they need to be adjusted

It's not so much that they're "adjusted" as it is that the lights are higher up to begin with. Thus, unless they're angled much further down than they would be on a normal car (which is impossible if you want to illuminate the same distance simply due to how high off the ground they are), they're going to project a brighter light into any car lower than those headlights.

it's called a Prius. Or a civic hatchback.

So you have a grand total of... six to choose from (the other two being the Mazda3, VW Golf, Corolla hatch and the Mirage, at least, until they get cancelled for the Corolla Cross and nothing, respectively). I'm ignoring the meme cars like Minis and Fiats because... come on.

It's not so much that they're "adjusted" as it is that the lights are higher up to begin with. Thus, unless they're angled much further down than they would be on a normal car (which is impossible if you want to illuminate the same distance simply due to how high off the ground they are), they're going to project a brighter light into any car lower than those headlights.

This is still not adding up.

If the light is higher off the ground and you want it to illuminate as far down the road as a light lower to the ground, it must be angled lower. If you raise the light and keep the angle constant, you will illuminate further down the road.

If the light is adjusted to keep the distance illuminated constant, I suspect that it would only be shining into vehicles at very short distances, and since you are not usually approaching vehicles head on and the lights have limited side spread, this shouldn't even be an issue. There's something else going on here.

So you have a grand total of... six to choose from

How many hatchbacks does a man need?

Why are you driving with your brights on?

It is mentioned in the IIHS article linked above that high beams are supposed to be used on roads with hardly any traffic.

Researchers from IIHS and the University of Michigan Transportation Research Institute found that drivers in and around Ann Arbor, Mich., didn’t use their high beams enough. Only 18% of drivers who were isolated enough to make use of their high beams did so.

Yes, that's true. I'm assuming that he doesn't live out in the sticks, but perhaps I'm wrong.

you can't buy a non-lifted hatchback

*laughs in Mitsubishi Mirage*

But, seriously, there are tons of non-lifted hatchbacks on the market.