Links to John Sadowski’s castle illusion seems to be going around all over the place lately. Not to be left out, I have to post a link as well. Really I just don’t want to forget the address, it is such a cool illusion. In one of my classes last year we covered some of the causes for optical illusions like this so it is very interesting to see how well this illusion works. None of the examples in the book were this cool. John even has a tutorial so I may try this out on some of my own photos someday.
More optical illusions with scientific explanations can be found here.