Predictions of Munsell values with the same perceived lightness at any specified chroma irrespective of hues—Determination of any tonal colors

Simple formulas are proposed for predicting the Munsell value of colors with the same tone (the same values for whiteness‐blackness, perceived lightness, and chroma irrespective of hue). The formulas can be used for any tone. In other words, the method can determine the Munsell value with the same perceived lightness at any specified chroma irrespective of hue. The chromatic strength (CS) function is only used for the derivations. The formulas are very simple, and can be used not only in the colorimetry but also in the color design field. The concept described in this study is that a common CS function can be used for transforming each of the three color attributes (hue, lightness, and chroma) from their uniform color space metric to their corresponding color appearance space attribute. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011     

Correlations between color attributes and children's color preferences

This study examined the role of color attributes (lightness and saturation) on children's color preferences for interior room colors. It also investigated children's most preferred colors among each of the five major hue families in the Munsell color system using scale‐models. Previous color preference studies have typically been done with small color chips or papers, which are very different from seeing a color applied on wall surfaces. A simulation method allowed for investigating the value of color in real contexts and controlling confounding variables. Forty‐five color samples were displayed on scale‐models to 63 children ages 7–11 years old. This study identified children's most preferred colors among each of the five major hue families in Munsell color system. It also demonstrated that saturation was positively correlated with children's preferences in the red, green, blue, and purple hue families. In the yellow hue family, interestingly, lightness has a positive correlation with preferences. Children's gender differences were found in that girls prefer red and purple more than boys. These findings lead to color application guidelines for designers to understand better color and eventually to create improved environments for children and their families. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 452–462, 2014     

Investigating the personality associations evoked by single colors: An exploratory study

Despite the crucial role of color appearance in forming first impressions, it is still not clear how color evokes personality associations—that is, a color‐personality association (CPA). This study aims to propose a method for quantifying the relationships between color attributes and CPAs for single colors. Specifically, we first collected the CPAs of five traits evoked by single colors (i.e., extraverted–introverted, moody–unemotional, agreeable–disagreeable, organized–disorganized, and wide interests–narrow interests) in a carefully controlled experiment. Then, multiple linear regression (MLR) analyses were adopted to predict these CPAs based on three color attributes (lightness, chroma, and hue). Our results showed that (1) the personality associations could be evoked by colors and perceived consistently by observers; (2) the relationships between the color attributes and the CPAs could be well quantified by separately conducting MLR analyses in different regions of hue (i.e., red, green, blue, and yellow regions); and (3) both lightness and chroma were significant predictors in almost all predictive models and they might have different relative importance or directions of effect when predicting the CPAs in different regions of hue, even for the same trait. This study improves the understanding of how color evokes personality associations and takes the first step toward developing the method for predicting the CPAs for multicolor combinations. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 388–396, 2017     

Proposal of an opponent‐colors system based on color‐appearance and color‐vision studies

A new theoretical color order system is proposed on the basis of various studies on color appearance and color vision. It has three orthogonal opponent‐colors axes and an improved chromatic strength of each hue. The system has color attributes whiteness w, blackness bk, grayness gr, chroma C, and hue H. A method is given for determining Munsell notations of any colors on any equi‐hue planes in the system. A method is also given for determining grayness regions and grayness values on hue‐chroma planes in the system. It is concluded that colors with the same color attributes [w, gr, bk, C] but with different hues in the theoretical space have approximately the same perceived lightness, the same degree of vividness (“azayakasa” in Japanese), and also the same color tone. The tone concept, for example used in the Practical Color Coordinate System (PCCS), is clarified perceptually. The proposed system is a basic and latent color‐order system to PCCS. In addition, the concept of veiling grayness by a pure color with any hue is introduced. Further, relationships are clarified between generalized chroma c(gen) and grayness. © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 135–150, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10234     

Influence of a holistic color interval on color harmony

This study investigates how a holistic color interval, i.e., the nondirectional color difference between a pair of colors in a CIELAB uniform color space, influences perceived color harmony. A set of 1035 test color pairs displayed on a CRT was evaluated for the degree of harmony. These test color pairs consist of pairs combined from among the selected 46 test colors evenly distributed in color space. The subjects were asked to select their three preferred colors from these 46 test colors and then to evaluate the degree of harmony of the test color combinations. The color intervals (ΔE) of each test color combination were calculated and treated as values of an independent variable. In addition, the evaluated degrees of color harmony were considered as values of a dependent variable, in which statistical analysis confirmed the relationship: the degree of harmony is a cubic function of the color interval. Moreover, the plot of this relationship allowed us to identify four color intervals: roughly corresponding to the regions of first ambiguity, similarity, second ambiguity, and contrast in Moon and Spencer's model. However, our results indicated that Moon and Spencer's principles for classifying harmonious/disharmonious regions in terms of the color interval for three color attributes—lightness, chroma and hue—may be inappropriate in predicting perceived color harmony. As for the color intervals between a pair of colors considered as a function of the three attributes, the interval for lightness may have a predominant effect on color harmony, expressed in terms of a cubic relationship. Results of the study further demonstrated that the subject's choice of colors significantly influences perceived color harmony. © 2001 John Wiley & Sons, Inc. Col Res Appl, 26, 29–39, 2001     

Global color impressions of multicolored textured patterns with equal unique hue elements

A global color impression from a multicolored textured pattern can be identified. It is not clear, however, how such a single color impression can be determined from the elemental colors of the multicolored textured pattern. To investigate this question, two hypotheses were evaluated. The first hypothesis is that a single color impression is determined by the colorimetric average of the elemental colors in the textured pattern (colorimetric average hypothesis). The second hypothesis is that the impression is influenced by the color appearances of the elemental colors in the textured pattern (color appearance hypothesis). Using an asymmetrical color matching method, the authors obtained single color impressions for random‐dot textured patterns consisting of two colors with the same unique hue and brightness but each with a different saturation. Our results showed that the matched colors were not located on the line connecting the two elemental colors of the pattern, but rather were on the curved unique hue loci line. Furthermore, the chromaticities of the matches shifted toward a higher saturation than the colorimetric averages. These results support the color appearance hypothesis and suggest that a single color impression from a multicolored textured pattern is determined by a mechanism that integrates the color appearances, i.e., hue, saturation, and brightness (or lightness), of the elemental colors in the pattern. In addition, it seems that the integration of the color appearances is not a simple process, because the apparent saturation of the color impression was higher than that of the colorimetric average and the average of the chromaticities of the colors in the pattern. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 267–277, 2007     

The representation of colors in spherical space

Color scaling experiments have established that perceived colors are distributed on the surface of a hypersphere in spherical space. A formal mathematical model of the color space is defined. Color differences as estimated by an observer are equal to the chord distance between corresponding points on the surface in spherical space. In one mathematical model are united: brightness, saturation, and hue as expressed in the empirical Munsell and NCS systems; complementary colors; large color differences; and contrast effects that are not represented in other models. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 113–124, 2008.     

Color preference affected by mode of color appearance

Most color preference research focuses on colors in an object color mode. In our daily life, however, colors are perceived not only as an object color mode but also as other modes, such as unnatural object color and light source color modes. To explore the effect of the color appearance mode on color preference, we examined the relationship between color preference and the mode of color appearance. Thirty‐three color chips were chosen from the Munsell notation varying in hues and chromas. The color chips were presented in different color appearance modes by changing the subject's room illuminance and the color chip room illuminance. The experimental results showed that the brightest and most saturated colors were preferred. It was found that the subject preferred color in a light source color mode and unnatural object color mode to color in an object color mode. Moreover, we found that hue had a small effect on color preference in the light source color mode. We also investigated the relationship between color preference and the perceived color attributes (perceived chromaticness, whiteness, and blackness). In a supplementary experiment, elementary color naming was conducted. The results showed that the perceived chromaticness, perceived whiteness, and perceived blackness play a role for the determination of color preference for different color appearance modes. We, consequently, suggest that color preference is dominated not only by color attributes but also by the mode of color appearance. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010     

An investigation into the impact of daylight on perceived color of façade: Understanding the role of chromaticness

Color selection has always been a classic problem in exterior color design for the simple reason that façade color is commonly chosen at the architect's office, regardless of different external conditions affecting color perception. This issue often leads to an apparent discrepancy between the selected color and the perceived color of façade. So far, extensive research has been carried out to identify, classify, and study the influence of these conditions on perceived color. However, little attention has been paid to the importance of color attributes. Hence, this article attempts to grasp better the significance of chromaticness, as briefly discussed in earlier studies, in the variation pattern of perceived color while daylight condition differs. In order to determine perceived color, each test subject was asked to compare the color seen on the façade to the standard color samples of natural color system index and choose the matching one, using a designed color‐measuring device. The results obtained from 93 participants demonstrate 3 things: First, they further support the belief that perceived color is influenced in both hue and nuance under varied daylight circumstances. Second, they confirm previous findings that indicated chromaticness would affect the extent of color shifts. And above all, a comparison of the results reveals that façade colors of higher chromaticness values have had less shifts in hue, yet greater shifts in whiteness. Finally, the findings suggest that chromaticness together with the external conditions, under which the color is to be seen, should be carefully considered when selecting the façade color.     

Whiteness,chromaticness, and blackness symmetries for CIELAB,with a numerical example

Whiteness, chromaticness, and blackness are defined for CIELAB. These NCS‐like color attributes offer an alternative to lightness and chroma for describing color. Their hue‐preserving symmetries are derived for tristimulus color space. A numerical example provides what theory predicts are visually uniform sequences of colors with constant lightness, whiteness, chromaticness, or blackness. Numerical approximation is unnecessary. Such sets of symmetric colors in one hue are visually interesting, and useful for computer aided design. The appropriateness of such attributes for CIELAB is briefly discussed. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010     

Hue,saturation, lightness,and building exterior preference: An empirical study in Turkey comparing architects' and nonarchitects' evaluative and cognitive judgments

This study investigated architects' and nonarchitects' evaluative and cognitive judgments of color on building exteriors. Thirty architects and 30 high school teachers living in Izmir, Turkey participated in the study. The experiment had two phases. First, participants viewed eight images, in which the color of a building exterior was manipulated with hues selected from HSB (hue, saturation, and brightness) color space. Participants were then asked to rate each image on 7‐point semantic differential scales measuring preference (like–dislike), arousal (arousing–sleepy), naturalness (natural–artificial), and relaxation (relaxing–distressing). Second, participants viewed the same building in nine saturation and lightness levels for each hue and picked the most preferred lightness and saturation level for each hue. Findings showed that for a building exterior: (1) yellow and blue were the most liked colors, (2) some hues were rated as more arousing, more natural, and more relaxing over the others, (3) gender had an effect on color preference and semantic ratings of naturalness and relaxation, (4) architects and nonarchitects differed in their color preference and semantic ratings of arousal and naturalness, and (5) full bright and moderate to low saturated colors and full saturated and moderate to high bright colors were preferred more. The results have practical implications for architects and urban designers. A successful coloration of a building exterior may increase its use frequency and economical value. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 395–405, 2008     

Experimental determination of laws of color harmony. Part 5: The harmony content of the various hue triads

We, in 1956 the Department of Architecture at the Budapest University of Technology and Economics, decided to start an extensive color harmony experiment. The experimental work, the collation, and processing of the collected data, lasting 50 years, was completed in 2006. The experiments described in this article are based on earlier experimental results obtained from investigation into the harmony content of hue pairs. We then decided to search for a third hue, which in association with an existing pair, with high‐color harmony, forms a hue triad with high‐harmony content too. The compositions prepared for the experiment were composed in each case of three hues of four identical saturation but different brightness, forming a group of 12 colors. The color content of the compositions covered the color space uniformly. That was the first stage in the experiment, carried out with 60 compositions. In the second stage, we investigated the effect of the saturation content of the colors used in the composition, on the harmony content of the hue triads. For this experiment, we prepared 48 compositions. In these experiments, we applied the method of grading. We concluded that the level of the harmony content of the hue triads depends on the inclination between the hue planes in the Coloroid color space. We also concluded that to every hue, selected for starting point, six well‐definable groups of hues can be ordered from the Coloroid color space, from which color triads with high harmony content, can be selected. It showed conclusively that the saturation level of the individual members of the triads has a significant influence on their harmony content. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011     

Optimal employment of color attributes to achieve saliency in icon matrix designs

With the wide use of smart devices, through which information is presented in vast quantities, objective guidelines are needed to enable designers to choose appropriate colors for information display. The purpose of this study is to determine which colors are the most eye‐catching in displays that employ icon matrices and thereby provide empirical grounds for strengthening the visual information structure of interface designs. Three attributes of color, which include hue, tone, and color combinations, are examined to optimize the color saliency in information displays. An eye‐tracking study was conducted to evaluate saliency objectively by analyzing fixations of visual attention. Based on the hue‐saturation‐brightness color system, a 5‐by‐5 matrix of 25 color patches was adopted to generate 21 color stimuli. Part I of the study focused on hue and indicated that warm colors are perceptually more eye‐catching relative to cool and neutral colors. Part II of the study investigated tonal influences and revealed that highly saturated colors provoked the greatest visual magnetism against a black background across all hue groups, although there was an alternative tendency for a blue hue. Contrary to expectations, no distinctive patterns were observed among brightness groups. With regard to color combination, Part III of the study provided empirical verification that high contrast between a foreground and a background generates a more dominant conspicuity. The results of the present study can be applied in designing electronic interfaces that display icon matrices to create effective communication by guiding visual attention and increasing aesthetic satisfaction. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 429–436, 2015     

Japanese and Korean ideas about clothing colors for elderly people: Intercountry and intergenerational differences

This study evaluated the clothing colors worn by elderly persons. We took photos, with elderly persons as models, displayed them on a computer screen, and used computer graphics to produce 75 colors of clothing worn by elderly persons. The 75 colors were evaluated by Japanese and Korean elderly women and female students. We compared the ideal colors and colors actually worn by elderly women in Japan and Korea. The ideal clothing color worn most often, and the images held concerning these colors, were found to differ between elderly women and female students in Japan and Korea, between Japanese and Korean elderly women, and between Japanese and Korean female students. In brief, the ideal clothing color for elderly women was the color satisfying brilliance, functionality, and elegance. We found that Japanese consumers prefer clothing of red hue or light grayish‐orange, whereas Korean consumers prefer colors of cold hues or achromatic colors. The differences observed between Japanese and Korean women seem to be associated with various factors, including traditions, culture, public morals, and racial consciousness. Differences in the rate of aging in the society and the timing of this change may also be involved. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 139–150, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10132     

Differences in attributes between color difference and color appearance (chroma and hue) for near‐neutral colors

Chroma‐step perception and its corresponding color difference in the same hue direction are the different attributes on color perception. The differences between them are different for different hues. Hue‐appearance step and its corresponding color difference along the same hue circle also have completely different concepts. The causes of the above two facts are clarified. The information based on various experiments and theoretical considerations are given for supporting the facts. In addition, it is clarified that the relationship on color‐appearance step and color difference has completely different characteristics between the quantitative (chroma) and the qualitative (hue) attributes of object colors. The importance of chromatic strength (CS) on hue is clarified in each of the three color attributes hue, value, and chroma. © 2004 Wiley Periodicals, Inc. Col Res Appl, 30, 42–52, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20073     

Effect of chromatic components on facial skin whiteness

Although the color measurement of facial skin becomes more common in dermatology and cosmetics, little is known about the relationship between subjective color perception and colorimetric values in facial skin. In this study, the possible relationships among perceived whiteness and the metric lightness, chroma and hue angle of Japanese females' facial skin color were investigated. First, the perceived brightness of the facial skin of Japanese females was evaluated visually and compared with metric lightness, chroma and hue angle, and the effect of hue and chroma on the perceived brightness was discussed. Second, a psychophysical experiment on the whiteness of the facial images and synthesized skin color plate images was conducted for examining the effect of hue and chroma on the perceived whiteness more precisely and independently. The results of two experiments showed that in regard to the facial skin color of the Japanese female, metric lightness disagrees with perceived whiteness or brightness in a narrow lightness range. The reddish facial skin color appeared brighter or whiter than that of a yellowish one in high lightness regions, and the low‐chroma facial skin color appeared brighter or whiter than a high‐chroma one. However, in the color plate images, a change in perceived whiteness by hue could not be confirmed, and the change in perceived whiteness by chroma was weaker than that from facial images. These results indicated that a higher‐level process of face recognition affected whiteness perception, and the criterion of facial skin whiteness was determined by facial skin color distribution. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011;     

Adequateness of a newly modified opponent‐colors theory

Two features of a newly modified opponent‐colors theory are examined for correctness: (1) The perceived chroma of pure color is different for different hues. This was confirmed by using Ikeda's UCS (Uniform Color Scales) formula and also by the maximum Munsell Chroma Values for different hues. (2) Chromatic colors with the same values of whiteness, blackness, grayness, and perceived chroma have the same perceived lightness and chromatic tone regardless of hue. This was confirmed by a theoretical analysis and observations of the color samples in the Practical Color Co‐ordinate System (PCCS) developed in Japan. Chromatic tone, a complex concept of object colors, is clarified. The structure of the newly modified theory and its corresponding color space were confirmed by observation of object colors. Furthermore, it was found effective for developing a color‐order system and its corresponding standard color charts to the modified theory. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 298–307, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10164     

Complementary colors theory of color vision: Physiology,color mixture,color constancy and color perception

I describe complementary colors' physiology and functional roles in color vision, in a three‐stage theory (receptor, opponent color, and complementary color stages). 40 specific roles include the complementary structuring of: S and L cones, opponent single cells, cardinal directions, hue cycle structure, hue constancy, trichromatic color mixture, additive/subtractive primaries, two unique hues, color mixture space, uniform hue difference, lightness‐, saturation‐, and wavelength/hue‐discrimination, spectral sensitivity, chromatic adaptation, metamerism, chromatic induction, Helson‐Judd effect, colored shadows, color rendering, warm‐cool colors, brilliance, color harmony, Aristotle's flight of colors, white‐black responsivity, Helmholtz‐Kohlrausch effect, rainbows/halos/glories, dichromatism, spectral‐sharpening, and trimodality of functions (RGB peaks, CMY troughs whose complementarism adapts functions to illuminant). The 40 specific roles fall into 3 general roles: color mixture, color constancy, and color perception. Complementarism evidently structures much of the visual process. Its physiology is evident in complementarism of cones, and opponent single cells in retina, LGN, and cortex. Genetics show our first cones were S and L, which are complementary in daylight D65, giving a standard white to aid chromatic adaptation. M cone later split from L to oppose the nonspectral (red and purple) hues mixed from S+L. Response curves and wavelength peaks of cones L, S, and (S+L), M, closely resemble, and lead to, those of opponent‐color chromatic responses y, b, and r, g, a bimodal system whose summation gives spectral‐sharpened trimodal complementarism (RGB peaks, CMY troughs). Spectral sharpening demands a post‐receptoral, post‐opponent‐colors location, hence a third stage. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011     

Research on color harmony of building façades

In this study, the 28 primary colors and 11 complementary colors suggested by Chang et al in their investigation on building colors in Wanhua District of Taipei City were taken as color samples. The two-color combination mode was adopted to obtain 308 simulation photos, and two-color harmony was discussed from the perspective of visual evaluation using psychophysical tests. This study explored building façade color harmony in the CIELAB color space, and the relationship between the color attributes (hue, lightness, and chroma) and the color harmony, and between the differences of the color attributes and color harmony. It found that a high lightness of a building's primary color is associated with a high level of building color harmony, while the color harmony is reduced when the color falls in the green or blue sector in the CIELAB color space; a greater lightness difference between building façade colors is associated with a higher level of building color harmony, while the colors are disharmonized when they tend to the blue sector in the CIELAB color space. The contribution of this study is to summarize the principles for the application of building color harmony in urban renewal, and proposed suggestions on building color harmony in the urban renewal process.