Wobbly Bobbly Illusion

I was just browsing our #animations category for good ol’ times sake, when I noticed I never shared this funny looking .gif with you. Pardon me if you’ve seen it before.

Anyway, if you concentrate at the centre of the spinning rounded rectangle on your right, you will notice it wobbles and giggles, changing its shape at the same time it spins. On closer inspection, one may notice there is nothing out of the ordinary going on, and that its shape stays the same at all times. Still, somehow the illusion occurs – Can you help me understand why? I can’t seem to figure this one out. Is it because of the “faulty” white pixels? You tell me!

25 Replies to “Wobbly Bobbly Illusion”

1. z2d4th says:

contraction and expansion illusion.. amazing

2. I think that any single frame is an optical illusion. When it moves it potentiates it. May the white dots potentiates it again the… OMG!

3. Awesome. Most likely because of the white pixels, if they were included in the gif, it would probably just rotate normally.

4. minecaricature says:

good one

5. Dipesh says:

It is because of the shape and not the white pixels. Take the centre as the centre of a circle whose radius is the edges of the rectangle, and rotate the circle. it is obvious that this effect cannot be seen in a rotating circle because of the uniform and regular surface. Where as in this case, when you are look at the rectangle, at on point you are looking at the edge which is equal to the radius and the next moment you are looking at its side which is in the area shorter than the radius and again the next edge and another side. the continuous movement of the length of radius creates the illusion.

Best regards

6. This is a really poor rendering, and it looks like there’s little to no antialiasing.

If the reader of this comment does not understand what antialiasing is, I’d advise reading the wikipedia article on it.
http://en.wikipedia.org/wiki/Supersample_anti-aliasing

If it was antialiased properly such that the edges aren’t so jaggy and full of defects, we would then be able to appropriately determine if the wobble comes from an optical illusion effect as opposed to a crappy image full of artifacts that appear to make something wobble.

7. The eye still see the the angle before it is straight and makes the lines appear uneaven.
the mind is a wonderful thing, it can trick the he** out us.

8. James says:

Wicked!

9. guesser says:

honestly, i believe it’s the way that the gif has the pixels transferred. the way the black square moves it looks like it’s bending. though it may be something else

10. Nevin says:

the wobbley bobbley is of irregular edges and it spins a bit off center. this is why it appears as it does.

11. Max says:

beautiful!

12. I was really impressed with this illusion, so I tried putting together a rotating SVG of it, for a smoother animation. I don’t yet allow you to control the rotation’s speed, but you can at least scale it to any size by resizing your browser.

Cheers,
-Dan.

13. Claudio says:

I would blame the aliased lines.

14. James says:

That’s pretty cool.

15. Julien says:

Distance from the side and from the corner are different. Your brain is confuse about that. I remember another illusion you post working the same way.

16. Florian Sulzbach says:

It printed out one frame of the gif and layed it on my old fashioned record player. The effect is there! So it can’t have anything to do with the pixels.

17. joseph says:

Apparently I talk to much. so i hope that clears it up for you

18. Louie says:

It looks jello.

19. ? says:

I like this!

20. Shamith says:

I think the wobbly bobbly illusion looks like that because of the way it’s spinning. If you stare, it will not change shape.

21. Barry says:

I just love these animated GIF illusions. Keep ’em coming.
Just one problem – I have the sound turned up but I can’t hear any giggling (apart from my grandkids who think I’m funny)

My wife thinks maybe you mean jiggle not giggle.

22. olivia says:

i didnt even have to stare at it.right when i clicked on the illusion after i searched ‘bob’,it started moving???????