Black point compensation
The Black point compensation option lets you control the output quality of shadow areas for CMYK source colors.
Black point compensation works by scaling the source colors so that the darkest point in the source profile maps to the darkest point in the output profile. Use Black point compensation to enhance details in shadows when the CMYK source space is larger than the gamut of the printer. In proofing applications, when the CMYK source space is smaller than the gamut of the printer, do not use this option.
Note: For RGB source colors, black point
compensation is always applied to Relative Colorimetric. Black point compensation does
not apply to Absolute Colorimetric. Photographic already scales the saturated colors and
shadow detail to the color capabilities of the output device, so black point
compensation is not relevant.