RGB Parade: Meaning & Definition in Film

The Color Balancer’s Guide

The RGB Parade is a specialized type of waveform monitor and is the single most important tool for objectively judging and correcting the color balance of a video image. While a standard waveform shows the combined luminance of an image, the RGB Parade ‘parades’ the Red, Green, and Blue channels next to each other as three distinct graphs. This separation allows a colorist to see the precise distribution of each primary color across the frame, making it incredibly easy to diagnose and fix color casts.

Reading the Parade

The principle is simple: for any part of the image that is supposed to be a neutral color (white, gray, or black), the levels of the Red, Green, and Blue channels should be equal. The RGB Parade makes this easy to verify:

• Balanced Image: In a perfectly white-balanced shot, the three separate waveforms will have very similar shapes and will sit at roughly the same height on the scope. The highlights will peak at the same level, the mid-tones will occupy the same space, and the shadows will bottom out at the same level.
• Unbalanced Image (Color Cast): If an image has a color cast, the parades will be visibly unbalanced. For example:
  • If the Blue parade is noticeably higher than the Red and Green parades, the image has a blue color cast.
  • If the Red parade is lower than the Green and Blue parades in the shadows, the blacks will have a cyan cast (because a lack of red results in a mix of green and blue, which is cyan).
  • If the Green parade is pushed higher in the mid-tones, the image has a green or magenta tint issue that needs correction.

The White Balancing Workflow

The primary function of the RGB Parade is to guide the colorist during the primary balancing process. The workflow is systematic:

1. Balance the Shadows (Lift): The colorist looks at the bottom of the parade and uses the Lift color wheel to adjust the color of the shadows until the three channels are sitting evenly on the black point (the ‘0’ line).
2. Balance the Highlights (Gain): Next, they look at the top of the parade and use the Gain color wheel to adjust the color of the highlights until the three channels are peaking evenly at the white point.
3. Balance the Mid-tones (Gamma): Finally, they look at the main body of the parade and use the Gamma color wheel to align the mid-tones.

By following this process and using the RGB Parade as an objective guide, a colorist can quickly and accurately remove any unwanted color casts from a shot, creating a perfectly neutral image that is ready for creative grading.