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Comment by jcranmer | Hacker News Reader

> For people who have two functioning eyes, the perception of depth is baked in.

Actually, my understanding is that the depth perception induced by binocular vision is relevant only within a relatively short range (like, single-digit number of feet away), which makes it relatively useless for long-distance depth perception needed for driving.

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A bit longer than this-- 10 meters or so.

So it's not useless for e.g. pulling into a parking spot or steering around a close vehicle.

(I'm crosseyed and don't benefit from binocular depth cues. For the most part I do alright, though rarely I'm comically off when someone throws me a ball or I'm picking up something close to me).

Do you swivel your head like an owl to get parallax? I find if I do that in inclement weather I feel better.

Nah. Maybe sometimes I lean forward and back a little to judge something, but people with binocular vision do that too.

Most of our depth perception isn't from stereopsis or other binocular cues.

Swiveling doesn't reall give parallax, you need lateral linear motion, think of a soccer goalie getting into position.

Rotating your head will give some lateral motion (your eye moves in space since the centre of rotation is your neck). You can see this easily by turning your head while focusing on an object in the foreground, your perspective on it will shift.

Side to side motion is actually what I meant and what I do sometimes in poor weather driving or when I have branches up close and blocking my vision while trying to see beyond them.

I have one eye. Can confirm its the same to me. Also always comically off with baseball and tennis. Pouring tea is also tricky for me unless I am holding both the pot and the cup.

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