Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Abstract: Color‐ Difference Perception and Scaling

Abstract: Color‐ Difference Perception and Scaling Fred W. Billmeyer, Jr. Ruth M. Rich Department of Chemistry Rensselaer Polytechnic Institute Troy. New York I2 I8 I and naive observers, etc., but requires careful and extensive In comparing visual to calculated color differences, we believe that the uncertainty of the visual observations far sample preparation. outweighs that from other sources, and that the visual task Where magnitude scaling is required, pair comparisons must be given major attention. We consider two such tasks: provide the simplest observer task while allowing full sta- tistical data treatment, but are limited to perceptibility judging the presence of a color difference, and judging its magnitude. studies. Category scaling, somewhat more difficult, can be There is virtually no information on the sizes of just- applied to acceptability questions also. Industrially, free perceptible color differences for surface samples: the scaling with a memory standard-the most difficult ob- MacAdam ellipses measure instead the standard deviation server task-is usual. We recommend the use of standard of color matching for colored-light stimuli. We have de- color difference pairs, most economically gray scales yet to veloped and will illustrate a method for deriving color-dif- be developed, simplifying the observer’s task to pair com- ference-perceptibility ellipses for surface samples. It can parisons, as a means of improving the reliability of industrial also be used to obtain acceptability data, to compare trained visual color-difference judgments. Abstract: The Case for CIELAB K. McLaren Imperial Chemical Industries Organics Division Blackley. Manchester, England The CIELAB equation, which is expected to become a CIE investigators, most notably Kuehni, when such formulas are Recommendation in 1976, is one of the most reliable applied to data not used for optimisation, the increases are equations ever developed for quantifying both the percep- usually not significant and in some cases a decrease occurs. tibility of color differences between surface colors and the The possibility of devising a formula which would permit acceptability of such differences by textile shade passers shade passing by means of a AE value which depended who are biased against chroma differences and more so solely on the closeness of match required is therefore remote against hue differences. It also possesses the even more and a formula which merely reduced the range of pass/fail important characteristic of permitting every color difference values required would not be worth adopting especially as to be readily split into its components of lightness, chroma if it were based on optimised ellipsoids, it would not permit and hue and even into the dyer’s variables of hue,’brightness ready splitting. and strength. The color space on which it is based possesses The CIELAB space and equation should therefore be most of the merits of Munsell space, but its cylindrical adopted by all industries wishing to quantify the differences coordinates are much more suitable for color specifica- between surface colors in place of the many equations tion. currently in use. It will be many years before any signifi- While statistically significant increases in correlation cantly better method-it will undoubtedly be far too com- coefficient have been achieved by optimisation by several plex to be expressed as an equation-is devised, and prog- ress towards this desirable goal is likely to be facilitated if Q 1977 by John Wiley & Sons, Inc. only one equation is used in the interim period. Volume 2, Number 2, Summer 1977 89 http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Color Research & Application Wiley

Abstract: Color‐ Difference Perception and Scaling

Download PDF
1 page

Loading next page...
 
/lp/wiley/abstract-color-difference-perception-and-scaling-k2ANfoME5x

References (0)

References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.

Publisher
Wiley
Copyright
"Copyright © 1977 Wiley Subscription Services, Inc., A Wiley Company"
ISSN
0361-2317
eISSN
1520-6378
DOI
10.1002/col.5080020210
Publisher site
See Article on Publisher Site

Abstract

Fred W. Billmeyer, Jr. Ruth M. Rich Department of Chemistry Rensselaer Polytechnic Institute Troy. New York I2 I8 I and naive observers, etc., but requires careful and extensive In comparing visual to calculated color differences, we believe that the uncertainty of the visual observations far sample preparation. outweighs that from other sources, and that the visual task Where magnitude scaling is required, pair comparisons must be given major attention. We consider two such tasks: provide the simplest observer task while allowing full sta- tistical data treatment, but are limited to perceptibility judging the presence of a color difference, and judging its magnitude. studies. Category scaling, somewhat more difficult, can be There is virtually no information on the sizes of just- applied to acceptability questions also. Industrially, free perceptible color differences for surface samples: the scaling with a memory standard-the most difficult ob- MacAdam ellipses measure instead the standard deviation server task-is usual. We recommend the use of standard of color matching for colored-light stimuli. We have de- color difference pairs, most economically gray scales yet to veloped and will illustrate a method for deriving color-dif- be developed, simplifying the observer’s task to pair com- ference-perceptibility ellipses for surface samples. It can parisons, as a means of improving the reliability of industrial also be used to obtain acceptability data, to compare trained visual color-difference judgments. Abstract: The Case for CIELAB K. McLaren Imperial Chemical Industries Organics Division Blackley. Manchester, England The CIELAB equation, which is expected to become a CIE investigators, most notably Kuehni, when such formulas are Recommendation in 1976, is one of the most reliable applied to data not used for optimisation, the increases are equations ever developed for quantifying both the percep- usually not significant and in some cases a decrease occurs. tibility of color differences between surface colors and the The possibility of devising a formula which would permit acceptability of such differences by textile shade passers shade passing by means of a AE value which depended who are biased against chroma differences and more so solely on the closeness of match required is therefore remote against hue differences. It also possesses the even more and a formula which merely reduced the range of pass/fail important characteristic of permitting every color difference values required would not be worth adopting especially as to be readily split into its components of lightness, chroma if it were based on optimised ellipsoids, it would not permit and hue and even into the dyer’s variables of hue,’brightness ready splitting. and strength. The color space on which it is based possesses The CIELAB space and equation should therefore be most of the merits of Munsell space, but its cylindrical adopted by all industries wishing to quantify the differences coordinates are much more suitable for color specifica- between surface colors in place of the many equations tion. currently in use. It will be many years before any signifi- While statistically significant increases in correlation cantly better method-it will undoubtedly be far too com- coefficient have been achieved by optimisation by several plex to be expressed as an equation-is devised, and prog- ress towards this desirable goal is likely to be facilitated if Q 1977 by John Wiley & Sons, Inc. only one equation is used in the interim period. Volume 2, Number 2, Summer 1977 89

Journal

Color Research & Application – Wiley

Published: Jun 1, 1977

There are no references for this article.