The arcane roots of colour psychology,chromotherapy, and colour forecasting

This article explores the genesis of the apparently disparate fields of colour psychology, chromotherapy, and colour forecasting. They came to the fore during the 20th century, and while ostensibly unrelated, their common ancestry lies in the late 18th and 19th centuries. This period witnessed the discovery of such strange forces as magnetism, electricity, X‐rays, and radio waves—in addition to odic forces and the colour aura. These were all invisible, mysterious, and to the public and many prominent scientists, equally plausible. This article traces a major influence back to spiritualism and Theosophy: both privileged colour and attributed powerful influences to it. This legacy remains, though not in the scientific domain. © 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 99–106, 2015     

The role of individual colour preferences in consumer purchase decisions

The purpose of this study is to test whether consumers' personal colour preferences (in an abstract sense rather than for a particular product) affect their intended product purchase decisions if they are given various colour choices. This work employs two experiments with visual components to investigate which colour a participant would choose if asked to select a product to purchase when there is a range of colours available. Two experiments were also designed to elicit a response about which colour each participant prefers (in an abstract sense). The study finds that personal colour preferences affect intended product‐colour purchase decisions but that the extent of this varies from one product category to the next. Further analysis reveals that personal colour preferences are secondary to factors such as colour functionality and colour performance. This work presents new experimental data about the role of colour in product and product packaging on intended consumer purchase decisions. A conceptual framework, supported by the experimental findings, are understanding the relationship between individual colour preferences and product‐choice colours, and more functional aspects of colour itself (such as the effect of colour on product's performance or functionality).     

Colour psychology and colour therapy: Caveat emptor

Information about colour psychology and colour therapy abounds in popular culture. Articles found in mass media as well as a plethora of Internet websites are often devoted to colour and a range of psychological, biological, and behavioral effects. The information available, which varies from scant summaries with catchy titles to lengthy and comprehensive discussions, is often presented in an authoritative manner exhorting the reader to believe a range of claims such as red is physically stimulating and arousing and blue is calming, relaxing and healing. However, empirical evidence or evidence of any nature is only rarely cited and, when it is, it's often in reference to findings that are inappropriately generalized or out‐of‐date and superseded. This article discusses a range of colour psychology and colour therapy claims found in popular culture and notes the similarities between these claims and the writings of early theorists such as Birren, Goldstein, Gerard and Luscher. While these authors have a valid if somewhat dated place in the literature on colour, there are a number of key reasons to be wary of colour psychology and colour therapy claims made in popular culture. These reasons are discussed in some detail and provide compelling support for applying the caveat emptor principle to colour psychology and colour therapy claims found in nonacademic sources. © 2010 Wiley Periodicals, Inc. Col Res Appl, 36, 229–234, 2011;     

The colour sensitivity of a colour matching recipe

The article examines the concepts of the following three quantities: partial colour sensitivity of a recipe to a particular colorant, colour balance of a recipe, and the overall colour sensitivity and the related property of colour robustness of a recipe. the way to calculate numerical estimates of the above quantities is extended from the case of CIE L *a*b* to the case CMC(l:c) colour difference formula. Results of a few numerical experiments are included for illustration and some possible practical consequences are discussed.     

The ULAB colour space

A new colour space, named ULAB, is developed. It is derived from the CIELAB colour space and can be converted to and from CIELAB. Unlike modified CIELAB colour‐difference formulae, ULAB incorporates corrections for lightness, chroma, and hue differences into its colour coordinates. For the small magnitude colour difference data, it shows the performance as good as more complicated formulae such as CIEDE2000. ULAB shows another chance of developing a colour space approximately more uniform than CIELAB. © 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 17–29, 2015     

The colour grading of fatty oils

The lightness or darkness of an oil, now commonly disregarded by the practical grader using the Lovibond system in the U.S.A. is shown to be of importance. Deceased     

The quantification of small visual colour differences

The Shademaster system, developed at UMIST, was used to explore the use of on-screen colour in order to assess the reliability of the CMC(l:c) formula as a measurement of small colour differences. Differences limited to almost pure hue, chroma and lightness changes around nine colour centres were judged by a group of ten observers. Each colour difference pair was presented on-screen in the form of a divided tile. The colour difference between each pair was measured using a Bentham telespectroradiometer and by a method using reverse transformation of RGB to CIE coordinates. The resultant measurements were used to determine the visibility of a particular colour difference, how that visibility varied from colour to colour and how it varied in different directions (i.e. hue, chroma or lightness). The data obtained from the judgements were used to construct perceptibility boundaries around each colour centre.     

The colour and fastness of natural saffron

Cotton and wool fabrics have been dyed with the aqueous extract of saffron containing α-crocin as the main colorant species. The dyeings were carried out with and without metal salts as mordants. The wash and light fastness of the dyed fabrics was studied. The colour of the fabrics was investigated in terms of CIE L* C* H* values.     

变色釉面砖的研制

变色釉是一种特殊颜色釉,在不同光源照射下,呈现不同的颜色。本文介绍低温快烧变色釉釉面砖的生产工艺、釉料配方。     

Professional colour communicator-the definitive colour selector

There are several systems available for the communication and selection of colours. A new system, allying precise colour differences to dye recipes, is the Professional Colour Communicator. James and Kevin Park tell us more.     

The effect of lighting changes on simultaneous colour contrast: a new aspect of colour rendition

Among the many metrics used to compute the colour rendition of a light source which have been investigated in recent years, most consider only the spectral power distribution of the light source being tested. To highlight aspects not usually considered in the development of colour rendition metrics, and to propose future directions for alternative approaches consistent with human visual perception, an experiment was conducted to examine colour appearance variations on certain spatial visual content configurations, in other words the effects of illusions under different light sources. Results indicate that stronger simultaneous contrast configurations have a more unpredictable variation in appearance. Therefore, it is proposed that colour spatial distribution should be considered for the future generation of rendering metrics.     

Universal models of colour emotion and colour harmony

A new set of quantitative models of colour emotion and colour harmony were developed in this study using psychophysical data collected from 12 regions in the world, including Argentina, China, France, Germany, Hungary, Iran, Japan, Spain, Sweden, Taiwan, Thailand, and the UK. These data have previously been published in journals or conferences (for details see Tables 1 and 2 ). For colour emotion, three new models were derived, showing satisfactory predictive performance in terms of an average correlation coefficient of 0.78 for “warm/cool”, 0.80 for “heavy/light” and 0.81 for “active/passive”. The new colour harmony model also had satisfactory predictive performance, with an average correlation coefficient of 0.72. Principal component analysis shows that the common colour harmony principles, including hue similarity, chroma similarity, lightness difference and high lightness principles, were partly agreed by observers of the same region. The findings suggest that it is feasible to develop universal models of colour emotion and colour harmony, and that the former was found to be relatively more culture‐independent than the latter.     

Effect of sleeve colour and background colour on change in colour assessments†

The two standard grey scales, ISO 105‐A02 and ISO 105‐A03, used for assessing change in colour and staining, respectively, are both typically provided mounted in black material and within a black sleeve. However, some grey scales are now provided mounted in grey material and within a grey sleeve. This paper reports psychophysical data and shows that the change in colour grades obtained from grey scales are not affected by the background colour of the viewing cabinet. A small, but statistically significant, effect is found for the colour of the sleeve with higher grades being found when using the black sleeve compared to when using the grey sleeve. However, when the samples being assessed are masked by a sleeve of the same colour as that used with the grey scale, an extensive field trial shows that the colour of the sleeve does not affect the change in colour grades obtained under commercial conditions.     

The thermochromic properties of the ceramic colour standards

Thermochromism is a reversible change oftransmittance, reflectance, or absorptance induced by a change of temperature. Photochromism is the corresponding effect induced by optical radiation. These effects can occur in the use of reflectance standards, as they may undergo a considerable temperature rise when subjected to the polychromatic irradiation used by many measuring instruments. An investigation of any thermochromic (and photochromic) properties of the twelve Ceramic Colour Standards is described. It is shown that thermochromic effects are only significant to a very small extent in about half of the standards and not at all in the remainder, while there is no evidence of any photochromism.     

Environment and colour: The technological interface

Technology and colour are viewed as interfaces between the environment, humans and human activity. Examples are provided of ways of facilitating and improving access to and use of colours by commercial users of colour coatings through improvements in the accuracy of measuring and displaying colour. By analogy, the task of providing effective interfaces within the coatings industry, between the coatings industry and the environment and between the coatings industry and the public and political domain are discussed. Examples of information shortfalls are cited to illustrate how distortions arise. Examples of more effective, integrated technological, organisational and political interfacing are culled from the author's experiences.     

Investigation of colour size effect for colour appearance assessment

Three psychophysical experiments were conducted to investigate the colour appearance changes between different sizes under various media or viewing conditions. The results are highly consistent that when increase stimulus size, the colour will appear to be lighter and more colourful with little change in hue. © 2010 Wiley Periodicals, Inc. Col Res Appl, 36, 201–209, 2011;