Maintaining consistent color for background keying

When you shoot footage against a colored background that will be keyed out in postproduction, use the Vectorscope and Waveform Monitor to ensure consistent results. The goal is to maximize the purity and saturation of the background as much as possible, without negatively impacting the foreground subject.

• The Vectorscope assesses the consistency and saturation of the background color. With nothing in front of the background, look for a tight signal concentrated out near the target for the color of the background. The tighter the signal, the more consistent the background. The farther the signal is from the center of the scope, the more saturated it is.

• The Waveform Monitor assesses the consistency of the brightness across the background. An ideally lit background shows a thin, straight line across the graph.

If you are continuing an previous shoot, use these tools to ensure that the color balance and brightness of the background hasn’t changed significantly. Confirming background consistency saves time in the editing application, letting you use the same keying settings for all clips.