Now that we’ve covered basic compositing enhancements and sky replacements, let’s move on to matte paintings, which are the first visual effects ever documented, and have been used almost as long as movies have existed.
The concept is simple: an image was painted onto glass, leaving holes that live action elements could be seen through. These paintings could then be attached to the front of the camera, or superimposed onto the film later. They were traditionally used to extend sets, particularly on period films. Often the lower story of a historic building would be built, with the rest painted to carefully match the perspective and lighting of the shot.
Unfortunately, this technique required the camera to be stationary, or for the two elements to be combined and a simple pan, tilt, or zoom added optically. The ability to create a painting that matches reality on film is a unique art, and it takes great technical skill to match them together seamlessly. Here’s an example of how this worked, and a few mattes painted by the old masters.
As optical printers and finally digital compositing developed, more techniques were invented to enhance matte paintings. Photographic elements like smoke and rippling water could be added to the final composite. Digital compositing allowed even more freedom, with matte paintings mapped onto multiple 3D layers and tracked to moving footage.
Below is a quick matte painting I put together. I didn’t have any footage designed for anything like this, so this is just the painting on it’s own. I found a few pictures of the Blue Ridge mountains to use as reference, and whipped together eight quick layers in Corel Painter 9:
click to enlarge
And there they are. I painted the mountains pretty flat, because I planned to add some 3D rendered mist elements in between each of the ranges. Then I tweaked the color a little, added a glow pass, and put together a camera move that separated the layers. I could have done this using After Effects’ 3D layers, as shown in this excellent tutorial by Andrew Kramer, but it was a simple horizontal truck, so I just panned each one individually at a different speed. Check a video file of the pieces and finished animation here (1.4mb, mpeg4 avi).
This a very crude painting, but with a few extra compositing tricks and a multiplane camera move it hasn’t turned out that bad. A more detailed matte painting (that had taken more than four hours) could be a lot more convincing. It’s not the most practical experiment, but shows what you can do with a few simple images.