Odd Illusion

[CaptainBlowhole]

How does this work? Ive seen similar things, but this one is bizarre.
In the distance, you see a building through an opening in the trees.
But as you approach it, paradoxically the building seems to get smaller and smaller ..


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[KnoxHarrington]

It's because you see just enough of the mill to assume that it must be a much bigger building than it is. As you get closer, you see the truth of the situation.

[CaptainBlowhole]

I was looking at one of the pipes on the building and it does seem bigger from further away. I know what you mean about seeing only a portion of it and then when you see the whole thing, its relative size visually shrinks, but still...

[Crash]

I think it's also because you're headed down hill. As you get to the bottom of the hill and the trees part you see the top and sides of the building for the first time.

Through the whole thing, the initial two bays of the building that you see first remain in frame. You go from seeing the base of the building to the whole building because of the angle of the road and the trees.

[StanUpshaw]

It's called the Ebbinghaus illusion. An object will appear to be different sizes depending on the objects surrounding it. It's exactly like how the moon appears so huge when it's on the horizon, compared to when it's overhead.

[TooCute]

The hole in the trees is much closer to you than the building is. So as you close in on the hole in the trees, it fills a progressively larger and larger field in your view. Meanwhile, since the building is so far away, it only takes up a marginally larger part of your field of vision. So ultimately, your perception of the size of the hole is growing way faster than the size of the building is growing - so relatively speaking, the building is shrinking.

[sailor]

They switch buildings when the other car cuts off your line-of-sight.

[Crash]

They switch buildings when the other car cuts off your line-of-sight.

This.

[Zipgun]

It's called the Ebbinghaus illusion. An object will appear to be different sizes depending on the objects surrounding it. It's exactly like how the moon appears so huge when it's on the horizon, compared to when it's overhead.

Wrong. In fact wrong about two things.

As far as the initial situation, I don't know if there's a name for it, but as mentioned earlier, it's that one is going down hill and the land horizon which is uphill is "rising" thus making the object in the background seem to shirink or sink.

And no, that's not why the Moon looks larger. First of all, your explanation doesn't work because there are no objects surounding the Moon to force a perspective. What you are seeing is magnification through vapor or what would be evaporation, humidity, etc, and that acting similar to a magnifying glass as water will tend to do. Just like if you were to put something in a pool, it would appear larger than it actually is.

[Crash]

Wrong. In fact wrong about two things.



Of course he's wrong. Everyone in this thread is wrong except Sailor.

Why are we still having this discussion?

[StanUpshaw]

And no, that's not why the Moon looks larger. First of all, your explanation doesn't work because there are no objects surounding the Moon to force a perspective. What you are seeing is magnification through vapor or what would be evaporation, humidity, etc, and that acting similar to a magnifying glass as water will tend to do. Just like if you were to put something in a pool, it would appear larger than it actually is.

:lol: I bet you're the sort of guy who goes around telling people they can balance an egg only on the equinox.

[Snoogans]

:lol: I bet you're the sort of guy who goes around telling people they can balance an egg only on the equinox.

yea either that or he just knows what he is talkin about and you dont

[StanUpshaw]

Oh jesus christ. Just read the wiki entry. The second paragraph explains why that's a load of shit.

[Snoogans]

yea but then it wouldnt be fun like it is to get you all worked up

[Zipgun]

Oh jesus christ. Just read the wiki entry. The second paragraph explains why that's a load of shit.

From Wikipedia:
Ebbinghaus illusion
From Wikipedia, the free encyclopediaJump to: navigation, search

The two orange circles are exactly the same size; however, the one on the left seems smaller.The Ebbinghaus illusion or Titchener circles is an optical illusion of relative size perception. In the best-known version of the illusion, two circles of identical size are placed near to each other and one is surrounded by large circles while the other is surrounded by small circles; the first central circle then appears smaller than the second central circle.

It was named for its discoverer, the German psychologist Hermann Ebbinghaus (1850-1909) it was popularised in the English-speaking world by Titchener in a 1901 textbook of experimental psychology, hence its alternative name "Titchener circles".[1]

Although commonly thought of as an illusion of size, recent work suggests that the critical factor in the illusion is the distance of the surrounding circles and the completeness of the annulus, making the illusion a variation of the Delboeuf illusion. If the surrounding circles are near to the central circle it appears larger, while if they are far away it appears smaller. Obviously, the size of the surrounding circles dictates how near they can be to the central circle, resulting in many studies confounding the two variables.[1]

The Ebbinghaus illusion has played a crucial role in the recent debate over the existence of separate pathways in the brain for perception and action (for more details see Two Streams hypothesis). It has been argued that the Ebbinghaus illusion distorts perception of size, but when a subject is required to respond with an action, such as grasping, no size distortion occurs.[2] However, recent work[3] suggests that the original experiments were flawed. The original stimuli limited the possibility for error in the grasping action, therefore making the grasp response more accurate, and presented the large and small versions of the stimulus in isolation—which results in no illusion because there is no second central circle to act as a reference. Franz et al. conclude that both the action and perception systems are equally fooled by the Ebbinghaus illusion.


How could I have been so blind? And who am I to argue with Wikipedia?

Well played, sir.

[Chigworthy]

It's pretty widely accepted that the moon appears bigger at the horizon because it is near the horizon, giving it perspective. That's why it is called an optical illusion. If the density of the atmosphere was somehow magnifying the appearance of the moon, it would be called an optical effect. Hold a ruler at arm's length and take a referential measurement of the moon at the horizon. Wait until it is higher in the sky, appearing smaller, and do the same. The measurement will be the same. If the atmosphere was somehow magnifying the moon, this would not happen.

[Zipgun]

It's pretty widely accepted that the moon appears bigger at the horizon because it is near the horizon, giving it perspective. That's why it is called an optical illusion. If the density of the atmosphere was somehow magnifying the appearance of the moon, it would be called an optical effect. Hold a ruler at arm's length and take a referential measurement of the moon at the horizon. Wait until it is higher in the sky, appearing smaller, and do the same. The measurement will be the same. If the atmosphere was somehow magnifying the moon, this would not happen.

You do realize that there's atmosphere in other places than just the horizon, right?

[Chigworthy]

You do realize that there's atmosphere in other places than just the horizon, right?

Of course I do. You were the one who said that the atmosphere was what caused the illusion. You've somehow confused my point with yours:



And no, that's not why the Moon looks larger. First of all, your explanation doesn't work because there are no objects surounding the Moon to force a perspective. What you are seeing is magnification through vapor or what would be evaporation, humidity, etc, and that acting similar to a magnifying glass as water will tend to do. Just like if you were to put something in a pool, it would appear larger than it actually is.

[Zipgun]

Of course I do. You were the one who said that the atmosphere was what caused the illusion. You've somehow confused my point with yours:

I can't say that doesn't happen, occasionally.

[StanUpshaw]

How could I have been so blind? And who am I to argue with Wikipedia?

Well played, sir.

http://en.wikipedia.org/wiki/Moon_illusion

Argue it if you'd like. I'd be happy to read your expert analysis.

[Zipgun]

http://en.wikipedia.org/wiki/Moon_illusion

Argue it if you'd like. I'd be happy to read your expert analysis.

Ehh... I don't buy it.

[Chigworthy]

Ehh... I don't buy it.

You don't have to. But due to the fact that it is so easy to prove, it really looks silly saying otherwise. On top of that, you've lined me up with Upshaw, which is very uncomfortable.

[Jujubees2]

I say it has something to do with the metric system.

[Crash]

Sailor, Sailor, Sailor...

[Snoogans]

wikipedia is usually pretty on point. For example, I took a small excerpt from the Wiki page for the 2007 New York Mets season page:

On July 12, 2007, Julio Franco was released by the Mets. [12]

Shortstop José Reyes was mentioned at mid-season as a possible MVP. Pedro Martínez notched his 3,000th strikeout. Tom Glavine got his 300th win. David Wright was getting meaningless hits and solidified the Mets as one of histories biggest embarrassments


see. dead on. Whoever edits these things is brilliant