The Munsell Color System and the Natural Color System are widely used but they have some limitations due to the manufacturing process and sampling choices. To estimate quantitatively these limitations we compared the colors of natural scenes with the colors represented by these systems under a wide range of illuminants. Spectral data from the two systems and from natural scenes were used in the analysis. It was found that a considerable portion of natural colors are not accounted by these systems, mainly colors with low lightness levels. Under D65 the Munsell Color System color volume corresponds to 72% of the Natural Color System color volume which in turn represents only 53% of the natural scenes color volume. If individual colors are considered, less than half are contained within these systems. To obtain a complete match to the natural colors contained by the color systems thresholds of 7 and 5 CIELAB units would be required for Munsell Color System and Natural Color System, respectively. Variations with the illuminant are generally modest showing that both system work similarly across different illuminations. Although these Color Systems have limitations in describing low lightness colors they perform quite well for medium to high levels of lightness.

中文翻译：

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使用Munsell和NCS色彩系统描述自然色彩

孟塞尔色彩系统和自然色彩系统被广泛使用，但是由于制造过程和采样选择的原因，它们具有一定的局限性。为了定量估计这些局限性，我们将自然场景的颜色与这些系统在各种光源下代表的颜色进行了比较。分析中使用了来自两个系统和自然场景的光谱数据。已经发现，这些系统没有考虑自然色的很大一部分，主要是亮度低的颜色。在D65下，孟塞尔色彩系统的色彩量相当于自然色彩系统的色彩量的72％，而自然色彩系统的色彩量仅占自然场景色彩量的53％。如果考虑单个颜色，则这些系统中包含的颜色不到一半。为了与色彩系统所包含的自然色完全匹配，孟塞尔色彩系统和自然色彩系统分别需要7个和5个CIELAB单位的阈值。光源的变化通常是适度的，表明两个系统在不同的光源下工作相似。尽管这些颜色系统在描述低亮度颜色方面有局限性，但它们对于中等到高亮度级别的表现都很好。