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Comment by mycodendral | Hacker News Reader

Can you cite some practical failure scenarios besides a wile e coyote billboard where camera inherently won't be able to accomplish what lidar/radar do?

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Cameras can obviously work at least as well as a human if they're attached to a human brain. The question is whether you can put enough compute and data together into a car to be able to do it live.

Why even bother when we can make artificial eyes that see depth? The price of LIDAR has plummeted and will continue to plummet. We already know that it works really, really well for self-driving with today's available compute+data.

> Cameras can obviously work at least as well as a human if they're attached to a human brain.

Eh, I mean I think that that’s necessary, but maybe not sufficient. Eyes are _really good_.

Fair point! Is there some advantage eyes have that wouldn't be surmountable with simply more cameras (i.e. to capture different exposure ranges etc)? I actually haven't thought about this side of it super closely, but I think you're right.

It's a question of cost and technology. Cinema cameras don't cost hundreds of thousands of dollars just because studios like spending money. Humans can see differences between even the best cameras on the market.

It's also a bit of a false analogy. Cameras don't really work like human vision. We do things like mesopic vision that simply aren't possible with current sensors. We have massively high resolution. We have async "pixels" that can respond immediately without waiting for a framing signal. Our brains process color in truly weird ways.

It's not like there's some physical law preventing computer vision from being better than human vision, but it's an incredibly difficult engineering problem that we've spent the better part of a century attacking without clearly winning.

Resolution; extreme dynamic range in a single exposure; sensitivity with short exposures in low light; focal range and speed of refocusing; white point adjustments (happening to a large degree in the retina as receptors become temporarily desensitized to a given wavelength with uninterrupted exposure). I’m sure there are more.

I can't see in the dark, can't see in the fog or the rain, can't see UV, my eyes only see in the rough direction my head is facing, there's a limited ability to track objects. Bicycles coming from behind are particularly easy to miss. Speaking of easy to miss, there's a hole in your vision m that you doing notice, where the optic nerve is. Hell, there's a whole body of work for times when human vision falls short and gets fooled, called optical illusions. There's another whole field of study about failures of the lenses and other parts in the eyes themselves. Some of those failures an electronic camera system is also going to have/have a reliance on components not being broken.

Given the number of shortcomings of human vision why shouldn't our self driving cars be designed to have better than human vision, especially if the goal is to not get into crashes. Humans, with human vision and human object tracking skills, and human reaction times get into crashes all the time. Shouldn't we want better and more sensors, which would lead to few fewer crashes, simply because better sensors have better data available?

As other commenters have noted, the kind of cameras that see better than human eyes cost more than a car.

Cheaper than that and you're making significant trade-offs.

It's not a given that a camera will even work as well as a human if it's attached to a human brain. The human eye is stereo, it has a focusable lens, an iris, it's incredibly sensitive and the foveated retina has a very high resolution. Can't say the same for the cheap-ass cameras on the Tesla. I'm not sure there is a camera on Earth that is the equal to the eye (yet).

Great points! The eye (really everything attached to a biological system) is fucking amazing.

Shadows. Everyone I know who's tried FSD learns very quickly that it's a random chance that the car will see an oncoming shadow (big truck, bridge, tree, etc) as a wall and either slam on the brakes or swerve.

If you have reliable depth information, ala LIDAR, you'll be able to know that there's nothing actually there.

Shiny truck trailers have been a failure case. A reflection of the sky in a truck back looks a lot like the sky from the right angle.

There are advertisements on the sides of trucks. Better question is why you are willing to dismiss the wile e coyote failure demonstration.

The wile e cayote failure was using tesla's cruise control rather than FSD. Binocular vision is sufficient.

Lidar will likely be outlawed anyway as it burns your retina. Dare you to put your eye (or cellphone camera) next to a waymo sensor for 10 sec and see what happens.

FSD catapults families into highway dividers, I'm pretty sure LIDAR will be fine

Virtually all LIDARs are class 1 devices, safe for human eyes to look at. Do you have any reason to believe Waymo LIDARs aren't class 1?

The rapid rotation and your blink reflex is apparently what makes it class 1 (supposedly). I don't see how a blink occurs if it isn't in visible spectrum. The science around the safety is very shaky, many tests look at only retina and not cornea damage.

https://www.laserfocusworld.com/blogs/article/14040682/safet...

Many of the class 1 lidars do damage camera sensors, is your eye really that much more resilient?

The damage at those wavelengths is just overheating. Your eyes are mainly water with its absurdly high heat capacity compared to pretty much anything in an image sensor. I'd expect eyes to be much more resilient in short duration, high intensity exposures and significantly better at long duration, low intensity exposures. LIDARs have been shifting towards short duration exposures to get higher intensities (for range) in recent years, simply to stay under the class 1 limits.

Heat damage doesn't make it safe, eyes are very sensitive to heat and while the cornea provides some protection, not everyone has a thick cornea due to surgery, and there is also evidence that heating the cornea causes cataracts.

The short exposure is putting a lot of faith in these device manufacturers. How do they guarantee short duration, are you confident that each manufacturer has sufficient electronics to stop the laser if the spinning slows slightly due to dirt, low power or a crash? Should the exposure limits be the same during day vs. night when your pupils are dilated?

LIDAR uses wavelengths that are transparent to the receptors in the human eye (but not to the sensors in many brand of cameras).

So, safe for human eyes but deadly for a camera.

It is funny you should say that binocular vision is sufficient when Tesla Vision hardware does not have binocular vision.

HW3 has three front-facing cameras that are not only too close together to provide binocular vision with adequate disparity, but also have different fixed focal lengths making them unable to establish binocular focus even if they were far enough apart [1]. HW4 has two front-facing cameras with the same limitations.

This is of course ignoring the fact that humans with visual acuity comparable to the HW3 cameras would almost be legally blind and not meet minimum vision requirements to operate a motor vehicle in, I believe, every state. HW4 cameras are better and you would only be unable to meet minimum vision requirements to operate a motor vehicle in most states, including California and Texas.

[1] https://en.wikipedia.org/wiki/Tesla_Autopilot_hardware#Tesla...

Sure, anything that involves fog.

How about this? https://www.bloomberg.com/features/2025-tesla-full-self-driv...

I was driving in convoy over closed (to non-convoy driving) mountain pass in Norway, in winter. Everything was white, you could barely see the road. Snow was so heavy that visibility stretched as far as the car before me, you couldn't see further than that. At some point a snow plug passed on the other side of the road and completely covered my windshield with snow, to the point that for a few second I had no visibility whatsoever. Good luck to cameras then.

In case it's helpful to know, Lidar also struggles to perform well in heavy snow due to the scattering and reflection of laser beams by snowflakes, which reduces the detectable range and can create false readings.

But you are also only a camera without LIDAR or RADAR, and you apparently navigated that situation successfully...

Fog

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