The shadow / reflection gives up the gig... she spins counter-clockwise (left).

Her foot alignment really makes it confusing but when you see the other details, you will see what I mean.


Look at the foot / leg that is lifted (it's shadow at bottom)... you'll see the correct motion. IF I just look at her, she can go either way.

That is pretty cool. I watched it for almost 15 minutes straight going counter-clockwise trying to make it switch with all the methods listed. I was about to give up, but after focusing on the feet for a few more minutes it just started going clockwise. I'd like to see how they came up with it.

The first two times I watched it, she was definitely going counterclockwise.
Then she seemed to be going clockwise for 3 more plays.
Then I realized I can make it go clockwise or counterclockwise at will depending on whether I link the moving shadow with the phase when her raised leg is behind her or in front of her.

Shadow of front leg moves across the screen => clockwise
Shadow of back leg moves across the screen => counter-clockwise

Since there is no reason the shadow would appear when her raised leg is in front but disappear when her raised leg is behind her, the shadow must correspond to when the raised leg is behind her. The disappearance of the shadow must occur because the shadow of the raised leg in front of her would be below the bottom of the screen. So it's correct to link the raised-leg-in-back phase with the shadow, and that forces a counterclockwise perception.

even with all the tips i still can't get her to spin counter-clockwise in motion. with still frames i can easily do the 'necker flip' though. curse my unyielding brain!

I wasn't able to see her spinning counter-clockwise until reading blankfist's comment about the outstretched leg being her left or right. Deathcow's note about up/down perspective helps too.

There are depth cues though - relative size of the outstretched leg, the curve of big toe to little toe, floor shadow, etc., but they switch as your perspective switches.

If you can make this girl spin counter-clockwise, you're F-in amazing..
this video is ?therapeutic? BTW.. would like my blood pressure tested while watching this

There are no depth cues and no 3D shading. It is as if you are looking at the projected shadow of a twirling ballerina, if that makes sense.

Hey that's intresting!
Well, the whole post is.

Still, even using SG's link no way I can get it counterclockwise. Only for a brief moment, less then a second, after many tries, she did it. And it was while I were concentrated somewhere else, reading the text and scrolling the page. But as soon as I turned, clockwise again. And even pretending not to fix her, or to watch her with the side of the eye, nothing.

I seem to have two right brain halves... Drives me nuts!

Next thing I will see spinning is my laptop out the window in a second (clockwise)

yikes. seems like 90% of people see her going clockwise. It took me using peripheral vision to get her to switch. Freaky though because she sort of skipped abeat in my mind when she switched. Amazing what the mind can imply.

At first i could only see her spinning clockwise, but after some practicing, i now see her switching from clockwice to counterclockwise if i look at the floor beneath her foot, and depending on the moment i watch the whole picture again, she turns either of both ways.

Pretty cool sift, first vid that made me go through the hassle of registering

I couldn't get this thing to spin counter-clockwise at all. I thought the same thing: "This is a 3D model, and it's rendered with her right leg extended. Though, last night, my gf brought the laptop to bed, and she was looking at it, and while I was laying down (looking at the screen sideways), I finally saw her spinning counter-clockwise. Finally!

It was a fleeting moment lost to history forever.

totally clockwise no matter what, for me.

and in the link SG posted first thing I noticed was the nipple.

what does it mean?

Am I the only one that can only see her going counter-clockwise?

Start by looking at the middle of the screen, clockwise.....if you begin from the ground up, counter....worked for me-

Strange, when I first watched it, it was going counter-clockwise. Then I scrolled down to read the description, and counter-clockwise describes me pretty well. Then I watched it again, and now it's spinning clockwise. I covered my left eye and just for a second it spun counter-clockwise, then went back to clockwise.