Apple Final Cut Pro 7 - Manual (Page 1311)

The shape of the Histogram graph is also good for determining the amount of contrast
in an image. A low-contrast image has few pixels in the extreme black and white ranges,
so the Histogram shows a concentrated clump of values nearer to the center of the graph.
By comparison, a high-contrast image has a wider distribution of values across the entire
width of the Histogram and may have spikes at white and black.
Low-contrast image High-contrast image
Learning to Read the RGB Parade Scope
The RGB Parade scope is like three side-by-side waveform monitors that display your
video as three separate red, green, and blue components. The waveforms are tinted red,
green, and blue so you can easily identify them.
High blue levels
1311 Chapter 78 Measuring and Setting Video Levels