Sewall L, Wooten B R
Department of Psychology, Brown University, Providence, Rhode Island 02912.
J Opt Soc Am A. 1991 Nov;8(11):1794-809. doi: 10.1364/josaa.8.001794.
Achromatic constancy refers to the invariance of either lightness or brightness despite changes in illumination intensity. Previous results disagree as to the extent to which constancy occurs with fixed luminance ratio conditions. This may reflect a lack of distinction between lightness and brightness. We measured both lightness and brightness constancy with fixed luminance ratios between test and annular fields under conditions varying in stimulus duration and adaptation. Lightness constancy occurred for all ratios under sustained viewing conditions and irrespective of adaptation level. Brightness constancy occurred for high-contrast stimuli and under sustained viewing conditions. These results support a bidimensional description of achromatic stimuli and suggest that lightness and brightness are the outcomes of two functionally distinct processes.
消色差恒常性是指尽管照明强度发生变化，但亮度或明度保持不变。以往的研究结果在固定亮度比条件下恒常性出现的程度上存在分歧。这可能反映出对亮度和明度缺乏区分。我们在刺激持续时间和适应条件不同的情况下，测量了测试场与环形场之间固定亮度比时的亮度和明度恒常性。在持续观察条件下，所有比例的明度恒常性均会出现，且与适应水平无关。高对比度刺激在持续观察条件下会出现亮度恒常性。这些结果支持了对消色差刺激的二维描述，并表明亮度和明度是两个功能不同的过程的结果。
