Perception of distance.

[Grandiagod]

I've been thinking about it for a while, and for the life of me I can't understand the physical reason why objects appear smaller at greater distances. I first thought that maybe the farther away you get the less photons get reflected back but that didn't make too much sense. Then I thought that it might just be a purely mental phenomenon, but once again, that didn't satisfy me.

Helps.

[T0rajir0u]

Re: Perception of distance.

Your eye is a sphere. Objects farther away subtend a smaller angle on your eye.

[Grandiagod]

Re: Perception of distance.

Your eye is a sphere. Objects farther away subtend a smaller angle on your eye.

Oh hell that was simple.

But if the eye was a flat plane objects would appear at the same size?

[Chrissi]

Re: Perception of distance.

Imagine if they WEREN'T smaller at greater distances. The world would look pretty ****ed up. I think that's a good enough reason.

[T0rajir0u]

Re: Perception of distance.

Oh hell that was simple.

But if the eye was a flat plane objects would appear at the same size?

Well, everything still has to project onto your eye, so no, it would be about the same. Only all weird and distorted.

[Grandiagod]

Re: Perception of distance.

Well, everything still has to project onto your eye, so no, it would be about the same. Only all weird and distorted.

Thanks Tora. Guess I just need to brush up on this stuff.

[UberMario]

Re: Perception of distance.

Makes me wonder how birds' eyes are shaped. They have everything in focus at all times.

[T0rajir0u]

Re: Perception of distance.

edit: what i meant to say is that it's impossible for anything with two eyes to have everything in focus at the same time do you even know what 'in focus' means

edit: oh well according to the first result on google apparently birds only use one eye at a time to look closely at things which might explain it

[Cavernio]

Re: Perception of distance.

Have you done lenses and mirrors in physics? That'd explain it more in depth.


If the eye were flat, there'd be no focus, right?

[Prince_Kheldar]

Re: Perception of distance.

Have you done lenses and mirrors in physics? That'd explain it more in depth.


If the eye were flat, there'd be no focus, right?

exactly, because the angle of reflection at which light would be coming back, would be everywhere, and it wouldn't "focus" it'd be like 1 big blur....

[Laharl]

Re: Perception of distance.

I am confused as to why this wouldn't be the case.

[ebs2002]

Re: Perception of distance.

Don't worry about the shape of the eye, instead think of the eye as a single point (if it makes it easier to picture, assume you're closing one eye).

Imagine an object 2 inches from your eye. Now draw a line from your eye to the top and bottom of that object. The angle is pretty big. Now move the object back an inch, and the angle is getting smaller.

The smaller the angle, the smaller the object.