Visual Clarity with a Black-and-White Scene

Visual clarity experiments are usually done with colorful test objects, and it is generally concluded that the results of such experiments are related to the color-rendering properties of the illuminants involved. Nonetheless, it has been observed that a clarity difference between illuminants may be seen, even with black-and-white objects. An experiment was performed to measure differences of perceived clarity using only black-and-white fabric and black yarn as test objects. The word clarity was not used in the instructions to subjects. They were asked questions concerning preference and blackness. The differences measured seem to indicate a role for color in black-and-white vision, but not a pure clarity effect independent of illuminant color.