Posted: Jul 21, 2018 9:03 am
by Animavore
Hermit wrote:One of my favourite optical trick is the ballerina. Her rotational direction keeps flipping every ten seconds or so, but not for everybody.

She never flips for me. She's always anti-clockwise. I can't even see how she could be the other way. I suspect it's because my imagination loads her with too many assumptions in my 3-D visualisation of her, that's to say I see her as a solid not as the flat that she is.