Scotopic contrast hues displaced toward red

Stabell, B. & Stabell, U. Scotopic contrast hues displaced toward red. Scand. J. Psychol., 1973, 14, 316–319.-The displacement of scotopic contrast hues toward red, contrary to predictions based on the opponent color theory of Hering, is explained on the assumption that the violet receptor system has a negligible sensitivity at the yellow cardinal point, while all the receptor systems are activated at the blue cardinal point.