This measurement method allows for the evaluation of the CAV luminance signal gain and for making chrominance/ luminance gain comparisons. Tektronix has developed the two-dimensional display called the “Lightning” display because of the zigzag trace pattern as shown below.

This display is created by plotting luminance versus B-Y in the upper half of the display and inverted luminance versus R-Y in the lower half of the display. The bright dot in the center of the screen is the luminance blanking level. The points above and below this show the plots of the different color components based on their signal amplitude. This test requires a color bar test signal be used.