Originally posted by krazyiven
reply to post by ThichHeaded

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are you serious??? is that really possible or are you joking??

Originally posted by ThichHeaded

Originally posted by krazyiven
reply to post by ThichHeaded

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are you serious??? is that really possible or are you joking??

No I am actually quite serious.. Try it sometime and report back with the results..

When we judge the size of an object near the horizon our perception is influenced by familiar terrestrial objects in the field of view (trees, houses, roads). We know from everyday experience that many of the recognizable things we see in the distance are quite far away. But when our gaze is upwards, we have no reference cues for distance, and judge things near the zenith to be closer than those on the horizon. Ibn Alhazan proposed this explanation for the moon illusion around 1000 CE.

Some experiments seem to support this explanation.

1- After-images of bright objects may be produced on the retina. Their apparent size depends upon where you look, being smaller when you look at a blank wall, or up into the sky, but larger when there are comparison objects in your visual field.

2- When one looks at the moon near the horizon through a hole in a piece of paper held some distance in front of the eye the moon appears smaller. The "horizon effect" largely disappears. One interpretation of this experiment is that the paper tube obscures any familiar reference objects. It seems to show that the moon illusion is due to direct comparison with reference objects of known size. Another interpretation is that the paper tube provides a visually dominating reference object already judged to be "near".

Some experiments cast doubt that these explanations are complete.

1- The moon illusion persists even when viewed on a dark night on a featureless plain, on the ocean, and even by airline pilots flying high above clouds. So reference objects of known size aren't the only basis for the illusion.

2- The moon illusion disappears (for most people) when they bend down and look at the moon between their legs. Or, if so inclined, one can view the moon by hanging from one's heels! At least two hypotheses have been proposed to account for this. (1) Familiar objects in the field of view may become useless as distance references because of their unfamiliar appearance when viewed upside-down. (2) The illusion may have something to do with our inner-ear's balance mechanism that tells us whether the head is upright or upside-down.

3- The method of viewing the moon through a hole in a piece of paper may also be used to view other objects. They too, appear smaller when viewed through the hole. Is our brain using the paper and the hole as a strongly dominant reference object? The nearby reference object is the paper; distant reference objects are hidden.

Not fully accurate, I concede it, but nonetheless beautiful, don't you think so?