One of our fans, mr. Jacenty found what appears to be the best hollow face optical illusion up to date. The hollow face illusion, as mentioned more than few times, gives you impression that the object you are seeing is embossed, while in reality it’s embedded. Sometimes the illusion works vice-versa as well. To remind you, convex equals embossed, while concave means embedded. First time I was introduced to this type of illusion, is when I saw Little Green Dragon video – the post that ranks well among top ten optical illusions of all time.
During my holidays in Spain in 2008 I found a nice optical illusion on one of the Barcelona’s houses. The head is concave, but with this lighting it looks like it is convex. Greetings from Calgary – Jacenty