Friday, 23 October 2009

Stereo and The Sun

Ill do my best to answer these two from Nikos, but the usual caveat: I'm not expert; use Wikipedia for a more definitive answer!

Ah ha...but does it explain why the sun appears to look bigger when it is closer to the horizon?

My understanding is that this illusion occurs because th esunrise/sunset puts the Sun 'alongside' things we 'know' the size of, rather than the high-noon position where it's 'in space'. False perspective, and all that.

Now, doesn't this second one remind you of something? The 'time to arrival' illusion of the TfL ad?

Are you easily offended, of a quiet nature, or are the young kids around?

If the answer to any of those is 'yes', turn the sound off before playing the next video!

What that shows is 'looming' and also the problems of a 'fixed heading' - no movement across the background until the pilot lifts the plane.

Yes but...rate of change of angle subtended - There must be a stereo image "angle" to this too (ie. depth/distance perception much more difficult for one eyed Gordon Brown compared to Mr Cameron?

There may be some stereo effect - but your eyes are [probably] only a few inches apart - what sort of an angle is involved in looking at an object 50 yards (or more) away? And 100 yards is 3 seconds at 30mph - just the sort of critical distance for you and a driver in a side road.

And three seconds is - coincidentally - all you really have with the Spitfire even when you know where to watch!


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