The letter C, for chrominance, makes simple sense, but the letter Y, for luminance, takes a
little explaining. It comes from a way of measuring color information that uses x-, y-, and
z-axes, where Y represents the luminance. The idea was originally to create a simple
system for recording color, and the use of Y to represent brightness, or luminance, stuck.Let’s test this display a little.
1. Continue using the Lady Walking sequence. Set the Timeline playhead to 00:00:07:00 so
you can see the lady against the smoky background.2. Set the waveform display to YC No Chroma. This is a brightness-only waveform, with no
color information, that shows a full range, with no limits set for broadcast television.The smoky parts of the image have little contrast and are displayed as a relatively flat line in
the waveform display. The lady’s head and shoulders are darker than the smoky
background. They’re around the middle of the image, and they are clearly visible in the
middle area of the waveform display.
3. Expand the Basic Correction section of the Lumetri Color panel.