If you want to know anything about how visual effects in film and video are achieved, there’s one word you should keep in mind…layers. All visual effects and optical illusions are constructed on the bases of images layered on top of each other. Before the advent of computers, visual effects were achieved by placing paintings in front of the camera, appearing on top of the action in order to create bigger and more fantasized locations. Another method was to reprint two layers of action into one single image to create an optical illusion.
As technology advanced, filmmakers perfected methods to composite images together to create optical illusions. These advances came with the advent of motion controlled cameras and chroma keying (also known as blue or green screening). The ability to remove a single colour (blue or green) from one image, and replacing the colour with another image.
We’re now in the digital age, we use computers for nearly everything, and so do filmmakers. Computers are now used for compositing images for optical illusion. They’re also used to create computer generated images. The most recent advancement is motion capture technology, giving a performer the ability to give life to a computer generated character. Whatever the method, the images created are always layered and composited from a range of sources to create a visual effect.
Are you thinking of creating a visual effect for your film or video and unsure where to start? Then here’s my advice. Start by drawing the shot you’re trying to create. Now break it down into sections, this could include location and background, performers, and anything else that is moving in your shot. Think about what sections of the image you are definitely able to capture in camera on a one to one scale. Now think about the sections of the image that are more of a challenge to capture in camera. Could you use miniatures, puppeteers, animation and/or computer generation? It’s in this section where blue or green screening becomes an effective method of separating your elements and compositing them together into one image.
Things to keep in mind when creating your images are the lines between where one section of your image meets another and the one to one scale elements you can not miniaturize which are light, water and fire.