The future of stop-motion animation | Brian McLean | TEDxPortland

Key Concepts

Persistence of vision, stop-motion animation, replacement animation, 3D printing (polyjet, color printing, voxel printing), digital fabrication, bespoke design, Leica, visual effects, medical applications of 3D printing, point cloud data, material properties, zoatrope.

Persistence of Vision and Animation

The speaker, Brian McClean, introduces the concept of persistence of vision, explaining that the human eye continues to perceive an image for approximately one-tenth of a second after it disappears. This phenomenon is crucial for creating the illusion of motion in movies, cartoons, and television. Without it, our vision would be interrupted by darkness every time we blink. Light hitting the retina causes a brief chemical reaction, leaving an impression. Rapidly replacing images allows the eye to perceive continuous motion. The brain plays a vital role, interpreting still images as a fluid sequence.

Stop-Motion Animation and Early Visual Effects

McClean recounts his childhood fascination with stop-motion animation, citing examples like King Kong, Rudolph the Red-Nosed Reindeer, Star Wars, Nightmare Before Christmas, and Wallace and Grommet. He notes that before the 1990s, stop-motion was the primary method for creating visual effects in film, relying on the skills of artists, technicians, cinematographers, and animators using relatively primitive tools.

The Introduction of 3D Printing

After studying art and initially resisting computers, McClean's career trajectory shifted when he encountered a 3D printer at a design school. He describes the 3D printer as a tool that bridges the digital and physical worlds, making the former more accessible. He emphasizes that creativity involves not only making things but also reinventing the methods of production.

3D Printing: From Mass Production to Bespoke Design

McClean contrasts traditional mass production, where identical objects are created, with the potential of 3D printing to produce unique, bespoke designs. He explains the 3D printing process, likening it to a CAT scan where a three-dimensional object is sliced into numerous two-dimensional images, which are then built up layer by layer. He uses the example of an inkjet printer creating an extruded "A" to illustrate the process. He highlights that with 3D printing, the complexity of the design does not necessarily increase the production time, allowing for mass production speed with individualized results.

Leica and the Pioneering Use of 3D Printing in Stop-Motion

In 2006, McClean and a small team at Leica, an animation studio in Oregon, began pioneering the use of 3D printing for replacement animation in stop-motion films. Their approach involved using computers to design face geometry, sending the data to a 3D printer, and then attaching the resulting physical faces to stop-motion puppets. Coraline was the first film to utilize this technique.

Color Printing and its Challenges

Early color printing involved spraying colored glue onto white powder, relying on the absorption weight rate between the liquid and the dry powder to create geometry and mixed colors. However, this method was susceptible to variations in humidity, leading to inconsistencies in color and size. Despite these challenges, it was the only color printer available at the time. The computer modelers at Leica had to function as both sculptors and engineers, designing both the external appearance and internal components of the faces.

Voxel Printing: A Revolution in 3D Printing

In 2016, voxel printing emerged as a groundbreaking advancement. A voxel is a three-dimensional pixel, with approximately 338 million voxels in a cubic inch. Unlike inkjet printing where colors can overlap, voxels must occupy their own 3D space. The printer deposits distinct voxels of cyan, yellow, magenta, black, white, and clear resin layer by layer in different patterns. The pattern of voxels needed to print a specific color varies depending on the shape of the object. Under an electron microscope, 3D printed faces reveal millions of distinct voxels, similar to a pointillist painting.

Advanced Control and Material Properties

Voxel printing allows for precise control over the interior of an object, not just the surface. Leica leverages visual effects software to translate dense point cloud data into 3D printed voxels, enabling the combination of hard and soft materials at a voxel level to create new materials with unique properties.

Medical Applications of Voxel Printing

McClean presents the medical applications of voxel printing, explaining how CAT scan data can be used to 3D print perfect replicas of a patient's body part, including bone, tissue, muscle, veins, and skin. Surgeons can use these replicas for practice operations, improving surgical outcomes. Leica's Rob Ducey co-authored a research paper on this topic.

Leica's Creative Use of 3D Printing

While 3D printing is commonly used for prototyping, Leica uses it as a form of creative expression, bringing still objects to life. Each face printed is unique and hand-finished by artists. For the film Missing Link, over 106,000 unique faces were printed. Leica maintains a face library and holds a Guinness World Record for the most 3D printed faces in a stop-motion animated film.

Live Demonstration: Persistence of Vision in Action

McClean demonstrates the principle of persistence of vision using a custom-built device on the TEDx stage. The device features a stop-motion puppet named Norman with interchangeable 3D printed faces. The device simulates the blinking of an eye at 24 frames per second, creating the illusion of motion.

Conclusion

McClean concludes by reflecting on his journey from a child fascinated by stop-motion animation to a pioneer in the use of 3D printing in the field. He emphasizes the importance of creativity in reinventing how things are made and the power of collaboration in bringing imagination to reality. He ends with a clip from Missing Link, highlighting the tedious nature of stop-motion animation and the dedication of the animators involved.