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Comment by pdonis | Hacker News Reader

> The gap between street lights (and hence the person) was in the field of view of the camera the entire time

But the gap between street lights is going to be very hard to see into.

> I'm confident my eyes are good enough that I would have been able to see this person at night in these lighting conditions.

I think you're overconfident. Human low light vision is very good if there is low light everywhere. But it is not good at seeing into low light regions when brightly lit regions are nearby.

That said, I agree that a visible light video camera is likely to be even worse that human vision under the given circumstances. But as others have commented elsewhere in this thread, the car is not just supposed to be using a visible light video camera. It has LIDAR and IR sensors, which should have clearly shown the pedestrian well before visible light did.

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FWIW the spot where the crash happened is in fact badly lit. I know this anecdotally from having been at the location for events -- it's right next to a concert venue -- but it can also be seen on other dashcam videos.

In this video [1] driving northbound, same as the vehicle in the crash, the car first goes under AZ-202, emerges under a streetlight, goes through a darker spot, then another streetlight (as you see the rocky outcrop), and then a very dark spot: and suddenly, you see a right-turn lane that wasn't there before. The latter dark spot is where the crash happened.

Another video by the same author, driving southbound [2], provides another useful reference. And these videos are three years old, yet the illumination of the roadway has not improved. Cameras exaggerate the contrast a bit, but not unreasonably so. The streetlights in question essentially aim directly downwards, illuminating the roadway immediately underneath, but much less of the surrounding air than other designs. This is responsible for the dark gaps, albeit it does significantly reduce light pollution.

[1] https://youtu.be/zEaTdYJExq8?t=8m50s [2] https://youtu.be/yfR7krN7z00?t=23m26s

EDIT:

Found more. The car in this video is going southbound, camera facing backwards [3]. This view faces the same way as the Uber did, but of course this video is moving away from the scene, and offset by a few dozen meters to the west. The drastic change in roadway illumination can still be seen.

In a fourth video [4], the car is going northbound, like the Uber, in the proper lanes, but the camera is pointing obliquely front-right. The illumination seems better, but you can still see the intensity of the shadows, including environmental shadows and the car's own shadow, as it moves between the lights.

[3] https://youtu.be/0Dum8Fj71JU?t=13s [4] https://youtu.be/6qHcuW_LCIU?t=16m45s

Is Tempe like Tucson in explicitly aiming for low light pollution? It does make for some nice star gazing.

Sadly, no.

Tucson does it due to the nearby observatory. The greater Phoenix area has a huge glow that washes out all the stars. You can see the glow as far away as Casa Grande when you come out of the little rocky pass on I-10 north of there.

Edit: removed a duplicated word.

> The greater Phoenix area has a huge glow that washes out all the stars.

I live in the Phoenix area, on the west side closer to Glendale (specifically, the border between Phoenix and Glendale is literally in my back yard).

There are times in the summer where the glow from the city is so bright, that rather than a dark sky (never black), you have a grey dimly lit sky instead.

Literally, "the sky was the color of television tuned to a dead channel" - maybe not as bright as the static Gibson was referring to, but still bright enough to see by - even without a full moon.

This area specifically is bad due to it's proximity to Sky Harbor airport.

Thanks for the links.

Everyone is moaning and slicing and dicing what the self-driving vehicle did wrong but, since you're familiar with the area: are pedestrians typically expected to be crossing this road?

Seems like the accident has a lot of factors that might not only be the self-driving car's fault, nor even a human driver that was fully in control. Regardless of how well people may want self-driving cars to do, one thing that can actually exist in the present is to make sure that we are creating safe ways for pedestrians to cross a road.

I've also driven around here a lot. No, pedestrians are not common. Maybe once a week in my experience? They do love to cross outside of crosswalks at night, though, and I've found that I have to adjust my own eyes' object recognition to look for moving shadows and not just moving lights, because they're very hard to see even in well-lit areas.

I've driven many thousands of hours at night and have dealt with a fair number of crazy pedestrians including a rather ... uncoordinated ... guy in Casa Grande who decided to go in circles on his bike in the middle of the road at around 3 AM for no discernible reason. Fortunately that place was much better lit and I was able to see him and stop until he got out of my side of the road.

So it's not that common, but yes, every so often you will see some person in black jaywalking across a wide road at night and they're quite hard to see. I don't think a lot of people appreciate that the streets here are wide & fast and that there just isn't that much pedestrian traffic even in daytime.

That was my suspicion. I've lived in very suburban areas before as well as rural ones where you might even be going 55 on a two-lane road with no street lighting whatsoever.

Here in LA, it's dense and traffic can't get up to very high speeds and we have relatively frequent places to cross safely if people choose to do so. I've definitely seen those who choose not to walk an extra 100 feet to wait at a crosswalk nearly hit in dusk or night traffic.

No amount of automation is going to bring the accident rate down to 0 so through a combination of factors, such as traffic and community design, we can work in tandem with automated driving to get closer. There's still the X factor of our human ability to do really dumb stuff.

The average speed limit here is 40, or 35 in the slow places and most roads are 4 lanes + a center median or turn lane, so yeah.

I've crossed these myself, but I always look both ways.

Wait, you don't cross lanes of traffic staring at your phone? That seems to be the new way people want to commit unintentional suicide.

This site lies on the approach route for Sky Harbor airport. I'd imagine the street lights are intentionally designed to reduce light pollution at the expense of "on the ground" effects.

> But the gap between street lights is going to be very hard to see into.

This wholly contradicts my experience driving at night on a street with street lights. I can't recall a time in my entire life I have had significant difficulty seeing into the gap between street lights. Keep in mind that the gap is not arbitrarily chosen.

Edited to note that I have experienced difficulties in low-vis conditions such as snow storms, sand storms, VERY strong rain storms, etc. None of which apply to this situation.

Also in those stormy conditions you slow down enough where the stopping power should roughly equal your visibility.

Keep in mind a lot of folks in this thread might be suddenly realizing they have reduced ocular ability at night, a likely common condition that pretty much nobody is aware of when it’s minor (because it’s not obvious something is amiss; maybe it’s just that dark). I agree with you that streetlights and headlights are almost universally sufficient in my experience. If they’re not, it’s worth getting your eyes checked out for light sensitivity at night. You never know.

I’m not sure a typical eye exam checks for it, either, because none of the tests I can think of seem like they’d be useful.

(As usual, an even keeled comment based on family experience is -2 and rapidly being silenced with zero feedback inside 5 minutes, which makes me wonder why I contribute to this community at all, probably time to stop)

I suspect it's too late to chnage now but have a "throwaway" account is an indicator you might not be committed to the community. one has to dig a little deeper to find out a multi year history with 4000 karma. so first impressions of your comments might be getting biased (it might just the "red car effect" but i am seeing a lot more throwaway accounts these days)

I would also not judge the community based on reactions to this very contentious thread - i am wary of jumping in on this one, but thought it worth noting your comment was not wildly out of place.

stay, we have cookies :-)

Judging a comment, or commenter, based on karma is asinine. Respond to comment, not commenter; ideas not people. You are not well representing HN, and this is my 'unpopular opinion' account talking. There are plenty of better ways to engage, and I do appreciate your enthusiasm for HN. Perhaps this is an apt introduction to the heated discussion that is HN.

This may be how you believe you see the world but most people take reputation into consideration and on sites which expose that information account age and karma are very popular cues for that.

Karma does not mean shit. It just means you are complaisant. I think the proper way to use things like HN/reddit is to always use a throwaway account and always speak your mind without the fear of negative karma...So I also agree 100% with the parent. Reply the comment, not the commenters, their karma or their entire history.

Well, in my view I was responding both to the comment ("i am leaving") and the commentor (making the years of participation and 4000 points relevant). If someone has been a contributor for many years then we should consider why they chose to leave. it might be them, it might be us.

I actually believe i am representing HN as a place where different opinions can be voiced, hopefully in a manner to generate light not heat. Heated discussions are rarely the useful or interesting ones to read.

Thank you for appreciating my enthusiasm.

PS Are you using two accounts - one ("my 'unpopular opinion' account) for saying things you fear people might not like? That seems odd. May I ask why?

Wouldn't a visual field test show this?

I did one at my last eye exam and it was pressing a button when you see dim flashes in all different locations. If you had low sensitivity, you wouldn't see those flashes and presumably you'd get a low score.

That test mostly isn't testing sensitivity, it's testing field of view which is an indicator of some potential eye health issues. It might end up testing sensitivity incidentally but that's not the purpose.

> Keep in mind that the gap is not arbitrarily chosen.

It's not supposed to be, no. But the gaps are not always optimal. The spacing of the street lights in the video (to the extent I can tell) seems to be quite wide, wider than I would think is optimal.

The edges of the "lightpool" that the lamps normally cast is probly being clipped by the cameras crappy dynamic contrast, it is almost certainly a much larger lightpool in real life.

> it is almost certainly a much larger lightpool in real life.

Not according to the post by niftich upthread.

https://www.youtube.com/watch?v=1XOVxSCG8u0

Not usually, and I say this as someone who has spent a lot of time driving nearby roads at night.

If Tempe is like Tuscon, they are using different kinds of street lighting from the rest of the country to minimize light pollution for star gazing reasons.

> But the gap between street lights is going to be very hard to see into.

Looking, right now, at a parking lot between two lights from a well-lit room. I can make out most of the outline of the black car in the middle of the "darkness" without any trouble. This isn't even the low light vision kicking in (which I agree isn't going to kick in if you're driving). Human vision should be able to make out the pedestrian earlier than the video footage.

How long does it take you to make out the black car and determine that it's a car? What if the car were coming straight at you out of darkness and you were standing in the light of a street lamp?

Also, are you looking straight at the car? Or are you looking elsewhere so that the car is in your peripheral vision, the way it would be if it were on the side of a road you were driving on?

A moving object would be more visible than usual. Human vision is better at picking up scene change.

Not when you transition from high to low light conditions. The problem is night vision has more noise which makes movement detection far more difficult. This is made worse because the pupil can't fully dilate making the gaps seem much darker.

This street in particular is weird at night because the street downstream rises up, and the light from those lamps is cast at a higher point. The place she was hit is extremely dangerous because there are no lights on her, and no lights behind her.

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