Hello world,
This illusion is interesting if you haven’t seen before. I am noting an explanation at the end, but do tickle your brain a little before reading it.
Our brain thinks that face is always convex. If you change angle of view, you expect certain facial features to become ‘hidden’. So if no features go out of sight it implies that the face is following your angle of view. This dragon’s face is painted on concave surface – so you can see the whole face over very wide range. Which the brain misinterprets as the movement 
8 responses so far ↓
Maria Moreno // September 15, 2009 at 7:05 pm |
Dear Shalin,
I’m just a PhD student attending FiO for first time, so I really appreciated the clues you give in your blog. Moreover, you are showing a lot of interesting topics!! For example, I also loved the Dragon paper craft. Actually, we created a OSA student chapter this year and we design a version of the Dragon for the local Science Fair, you can show it here!:
http://www.ifisc.uib-csic.es/osa
/index.php?option=com_content&view=article&id=54:science-fair-in-menorca&catid=37:events&Itemid=54
Tons of thanks for your outreaching work.
Have fun!
Shalin Mehta // September 15, 2009 at 7:47 pm |
Hi Maria, Thanks for pointing out your ‘Spanish horse’
The printable version that you provide (http://www.ifisc.uib-csic.es/osa/images/stories/caballo_instrucciones_colorblack.pdf) is much more suited for high-contrast B&W printing than other versions on the net. One of this will soon be on my desk! We are a new OSA chapter as well (just one year old) and we are still planning our first outreach – so we have good deal to learn. See you at FiO!
Dan Franzen // October 16, 2009 at 2:11 am
I have to say that I’m mystified by some of those so-called optical illusions on the Scientific American page. I can see the issue with the Pisa tower, but none of the other ones seem to be illusory at all. For example, the Petronus Towers. The text claims that to us the towers appear to be converging as our eye travels from bottom to top – with the idea being that objects in the distance converge – but to my eye this is completely untrue: the distance between the towers at the top looks exactly the same as that at the bottom. There is no illusion.
Dan Franzen // October 1, 2009 at 3:47 am |
I believe I have seen this illusion before; it’s an excellent mindbender. Thanks for posting it!
Good luck at FIO ‘09.
Christina Folz // October 1, 2009 at 3:51 am |
That is so cool! Have you seen this one: http://www.scientificamerican.com/slideshow.cfm?id=a-perspective-on-3-d-visual-illusions. It totally blows my mind.
Shalin Mehta // October 1, 2009 at 7:47 am |
Very interesting! Thanks for sharing this link. I couldn’t believe two images of the leaning tower were the same. It points out that we do not directly perceive depth, but infer it using visual cues based on some rules. I wonder how do we learn these rules in the first place and could we learn the exceptions too? Perfect question to ask at FiO.
Joseph Chan // October 12, 2009 at 7:31 pm |
Dear Shalin:
Really love this paper dragon illusion. Do you have any idea where I can find more of the likes? I believe I’ve seen a few that do similar tricks but for buildings and scenery in an art show earlier this year but have no idea where to start looking.
Or would you know of any tips on the next on how to create illusions like these ones yourself?
Much appreciated!
Shalin Mehta // November 26, 2009 at 10:55 am |
This is a fascinating talk on the topic of optical illusions (or rather our visual perception): http://www.ted.com/talks/lang/eng/beau_lotto_optical_illusions_show_how_we_see.html