Psychophysical experiments of colour appearance, in terms of lightness, colourfulness, and hue, were conducted outdoors and indoors to investigate whether there was any difference in colour appearance between outdoor and indoor environments. A panel of 10 observers participated in the outdoor experiment, while 13 observers took part in the indoor experiment. The reference white had an average luminance of 12784 cd/m² in the outdoor experiment and 129 cd/m² in the indoor experiment. Test colours included 42 colour patches selected from the Practical Coordinate Color System to achieve a reasonable uniform distribution of samples in CIECAM02. Experimental results show that for both outdoor and indoor environments, there was good agreement between visual data and predicted values by CIECAM02 for the three colour appearance scales, with the coefficient of variation values all lower than 25 and the R² values all higher than 0.73, indicating little difference in the three dimensions of colour appearance between indoor and outdoor viewing conditions. Experimental data also suggest that the observers were more sensitive to variation in lightness for grayish colours than for highly saturated colours, a phenomenon that seems to relate with the Helmholtz‐Kohlrausch effect. This phenomenon was modeled for predicting perceived lightness (J′) using the present experimental data. The new J′ model was tested using three extra sets of visual data obtained both outdoors and indoors, showing good predictive performance of the new model, with an average coefficient of variation of 14, an average R² of 0.88, and an average STRESS index of 14.18.

中文翻译：

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室外和室内环境中表面颜色的颜色外观比较

在室内和室外进行了关于亮度，色彩和色调的颜色外观的心理物理实验，以研究室外和室内环境之间的颜色外观是否存在差异。由10位观察员组成的小组参加了室外实验，而有13位观察员参加了室内实验。在户外实验中，参考白色的平均亮度为12784 cd / m ²，平均亮度为129 cd / m ²在室内实验中。测试颜色包括从“实用坐标颜色系统”中选择的42个色块，以在CIECAM02中实现样品的合理均匀分布。实验结果表明，对于室外和室内环境，三种颜色外观等级的视觉数据与CIECAM02的预测值之间都具有良好的一致性，变异系数值均小于25，R ²值均高于0.73，表明室内和室外观看条件在颜色外观的三个维度上几乎没有差异。实验数据还表明，观察者对浅灰颜色的亮度变化比对高度饱和颜色的颜色变化更敏感，这种现象似乎与亥姆霍兹-科尔劳斯效应有关。使用当前实验数据对该现象进行建模，以预测感知到的亮度（J'）。使用从室外和室内获得的三组额外的视觉数据对新的J'模型进行了测试，显示了新模型的良好预测性能，平均变异系数为14，平均R ²为0.88，平均STRESS指数14.18。