About Color Bars
Color bars are electronically generated video signals that meet very strict specifications.
Because the luma and chroma levels are standardized, you can use color bars passing
through different components of a video system to see how each device is affecting
the signal. For example, suppose you record color bars that have a 100 percent white
level in a camcorder and then play the videotape back on a VTR. If the white level
output from the VTR is only 90 percent, you know that you need to increase the luma
level output of the VTR.
NTSC and PAL each have specific color bar standards, and even within NTSC and PAL
there are several standards. When you evaluate color bars on a video scope, it is
important to know which color bar standard you are measuring, or you may make
improper adjustments. “SMPTE bars” is a commonly used standard.
The Flesh Tone
line is here on
the Vectorscope.