short key/black

short key/black (In French noir court) in achromatic composition as well as in modified chromatic composition with UCR, the increased use of the achromatic process color black (K) instead of the three chromatic colors CMY in the three-quarter tones, going as far as the solid tones, in the area of the three-color gray axis, that is, only in a short section of the tone value range. The tone value at which the characteristic curve of the short black begins is called the starting point.