Tuesday, July 07, 2009

Optical Illusion of the Day

You might remember that I posted a link a while back to this awesome optical illusion of a spinning silhouette. (I can't find my blog entry on it at the moment, so I must not have tagged it very well.) Here is a more generic but still cool optical illusion that I mentioned previously.

Well, here is another really awesome optical illusion, which was posted on Bad Astronomy. Damn! It's probably not as cool as the silhouette, but I still really like it. It also makes me thing of the green/blue paradox (or whatever that's officially called). :)

Also, here is an aural illusion that I can't get to work. I get exactly the same thing whether or not my eyes are open or closed. Can somebody explain this one to me?

(Tip of the cap to Rob Neyer.)


Sumeet said...

The aural one works for me; with eyes closed I hear the actual sound, "ba ba...", but with eyes open I hear either "ga ga..." or "d̪a d̪a..." (this seems to vary between runs). The reason is apparently that the lips need to come together to produce the /b/ sound, but this doesn't happen in the video. The effectiveness of this illusion probably varies somewhat with factors like native language; for a native speaker of a language with a large tonal range, such as Hindi, presumably visual cues are more important.

The blue/green illusion is just incredible.

Mason said...

It occurred to me that somebody like me who might not be good at looking directly at people's faces when in conversation (I have actually been told this before by own of my friends, and it's probably a bad habit I need to break) might notice less of a difference when my eyes are closed simply because of my usual habits.

GFreak said...

I notice only a very slight difference in the aural "illusion". I definitely hear the "ba ba ba" when I'm not looking, but when watching it I would consider it "indeterminate".

The visual illusion is so drastic, I had to verify it myself. I saved the image, loaded it in MS Paint, and "blacked out" a few segments of magenta and orange. Fantastic.

By the way, how's my "use" of "quotes"?

Mason said...

"Your" use of quotes "is" "awesome".