Chroma to Luma Help

Intro

Use this feature to view the intensity of the red or blue channel at one glance.
The cb or cr channel displayed is similar to the RGB red or blue channel, but not identical.
Horizontal line doubling is used to make up for the chroma subsampling.

Blue/red/both/chroma movie

To view the blue/red channel as a greyscale movie, choose blue/red.
"Both" adds the blue and red amplitude. The result is a movie that shows the colorfulness of the original movie.
"Chroma movie" yields a movie that shows how little chroma contributes to contrast by itself. The brightness of the movie is set to medium grey.