There are a variety of differences in 2D and 3D animation. 2D animation is an art form that gained widespread popularity in the 19th century, with the creation of the zoetrope and flip books, and was later refined by pioneers such as Walt Disney. The advance of computer technology allowed for the rise of 3D animation, which is now commonly used for creating special effects in feature films. Although both are forms of animation, the capabilities of each and the processes for creating them can differ significantly.
Creating Animation
3D animation can only be created on a computer, using such programs as 3D Studio Max or LightWave 3D. Although 2D animation can also be created on a computer, using such programs as Adobe Flash, a 2D animation can also be created using a pad of paper, with individual hand drawings rendered on each page to simulate movement.
Movement
Objects in 2D animation can only move along a horizontal (x-axis) for simulating forward and backward movement, and a vertical (y-axis) for up and down movement. In 3D animation, objects can also move closer or farther away from the person viewing the animation (along the z-axis). If you want an object to appear closer in a 3D animation, you would move it closer along the z-axis. In a 2D animation, the object must be drawn larger to create such an effect.
Objects
Objects in 2D animation are flat, like a painting or photograph. If you view the front of a house in a 2D animation, that is the only part of the house that exists in the animation. In 3D animation, objects are like sculptures. They have a front, back, top and bottom side. Therefore, you could view a 3D house from any angle.
Camera
3D animation programs use a virtual camera as part of the animation process. This camera has many of the features of an actual camera, including focal length. The camera can also move in a similar manner as an actual movie camera, which includes zooms, pans and dolly shots. Such advanced technology is not needed to create 2D animation.
Lighting
3D animation programs use virtual lights that can simulate spotlights, light bulbs or even the sun. They can also use colored lights or multiple light sources to create a variety of special effects. Objects passing in front of these lights cast realistic shadows on other objects in the scene. In 2D animation, shadows must be drawn by hand.
Realism
3D animation, through the use of 3D models and realistic textures, can create images that are virtually indistinguishable from real life. Even the highest quality 2D animation still has a cartoon-like, hand-drawn appearance.
Motion Capture and Rotoscoping
To make the animation process easier, 3D animation may use a process called motion capture. This involves an actor wearing a special suit with dozens of points on it. As the actor moves, the camera uses these points as a reference for animating a 3D character. Several points may also be used on the actor's face to capture facial expressions and mouth movements for dialogue. 2D animation cannot use motion capture, but can use a similar process called rotoscoping. This involves tracing over live footage of actors, frame-by-frame, to help create the animation.
Special Effects
In 2D animation, special effects such as fire, smoke, moving water and explosions must be painstakingly drawn for each frame. In 3D animation, these effects can be generated by plug-ins or special filters, which generate the animated effect automatically after indicating some parameters.
