The video signal level which is intended to produce monitor black level in the reproduced image. In systems with a setup level, i.e., the 7.5 IRE setup in a 525/59.94/2:1/NTSC composite video documented by ANSI/EIA TIA 250-C and SMPTE 170M, reference black is at the setup level. In systems with no setup level, reference black is at blanking level.