Game Development Reference
Figure 10.2 The green screen
footage composited with other
elements with the green screen
usually eliminate most spill with the clever placement of light-
ing on your subject, and by keeping your subject away from the
blue or green screen.
Keep a Clean Screen
It's a really good idea to make sure that your blue or green
screen is completely uniform. In other words, you want the entire
screen to be the exact same shade of blue or green. Oftentimes,
these screens are created with hanging pieces of large fabric.
Like most fabrics, they wrinkle easily. Wrinkles cause variations
in color, causing keying to become a more challenging process.
Many green screen studios even use extra material to create
rounded corners where the walls and fl oor meet. This is so that
there are no shadows. Shadows and wrinkles (or any variations in
color or luminance) in the blue or green screen add a great deal
of headaches into any keying job.
Previewing Your Key
When I fi rst started learning about keying in After Effects,
I would import footage with a blue or green screen, and then