optical illusion

9 Articles

Before Film There Were Zoetropes. Now We Have 3D Printed Zoetropes!

March 25, 2015 by 15 Comments

Reddit user [eyelandarts] has produced a rather unique 3D printing project. A 3D printed Zoetrope.

You see, a zoetrope was a device that created an animation effect that pre-dates film technology. It would create the illusion of motion much like a flip book does, but with a spinning cylindrical wall with slots cut into it. As the cylinder spins, you catch a glimpse of the animation through the slots. But, it’s just a 2-dimensional animation — what if you replaced it with an ever changing 3D model?

It’s actually been done before. A long time ago in fact. In 1887, [Etienne-Jules Marey] created a large zoetrope to animate plaster models of a bird in flight. Fast forward to today, and [eyelandarts] has 3D printed something similar — but ditched the cylindrical wall. Instead, a strobe light is used to see the animation!

The end result is quite awesome if we do say so our-selves. For another fun take on Zoetropes — how about a digital one made out of tiny LCD screens?

Siezure-warning… there’s a very flash-tastic demo gif embedded after the break if you’re brave enough to view such a thing.

Continue reading “Before Film There Were Zoetropes. Now We Have 3D Printed Zoetropes!” →

Spliced Animations Come To Life On Their Pages

January 16, 2015 by 15 Comments

Remember those flipbooks you doodled into your history textbooks while you waited for the lunch bell? [Maric] takes the general principles of flipbooks and turns them on their head, giving our brain a whirl in the process. By splicing multiple frames into one image, he can bring animations to life onto a single page.

The technique is simple, but yields impressive results. By overlaying a pattern of vertical black bars onto his image, only a small fraction of the image is visible at any given point. The gaps in the pattern belong to a single frame from the animation. As [Maric] slides the pattern over the image, subsequent frames are revealed to our eyes, and our brain fills in the rest.

A closer look reveals more detail about the constraints imposed on these animations. In this case, the number of frames per animation loop is given by the widths in the transparency pattern. Specifically, it is the number of transparent slits that could fit, side-by-side, within an adjacent black rectangle.

The trick that makes this demonstration work so nicely is that the animated clips finish where they start, resulting in a clean, continuous illusion.

Don’t believe what you see? [Maric] has linked the pattern and images on his video so you can try them for yourself. Give them a go, and let us know what you think in the comments.

Continue reading “Spliced Animations Come To Life On Their Pages” →