ASTM D2244-23

Standard Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates

SIGNIFICANCE AND USE
5.1 The original CIE color scales based on tristimulus values X, Y, Z and chromaticity coordinates x, y are not uniform visually. Each subsequent color scale based on CIE values has had weighting factors applied to provide some degree of uniformity so that color differences in various regions of color space will be more nearly comparable. On the other hand, color differences obtained for the same specimens evaluated in different color-scale systems are not likely to be identical. To avoid confusion, color differences among specimens or the associated tolerances should be compared only when they are obtained for the same color-scale system. There is no simple factor that can be used to convert accurately color differences or color tolerances in one system to difference or tolerance units in another system for all colors of specimens.  
5.2 Color differences calculated in ΔE00 units (6) are highly recommended for use with color-differences in the range of 0.0 to 5.0 ΔE*ab units. This color-difference equation is appropriate for and widely used in industrial and commercial applications including, but not limited to, automobiles, coatings, cosmetics, inks, packaging, paints, plastics, printing, security, and textiles.  
5.3 Users of color tolerance equations have found that, in each system, summation of three, vector color-difference components into a single scalar value is very useful for determining whether a specimen color is within a specified tolerance from a standard. However, for control of color in production, it may be necessary to know not only the magnitude of the departure from standard but also the direction of this departure. It is possible to include information on the direction of a small color difference by listing the three instrumentally determined components of the color difference.  
5.4 Selection of color tolerances based on instrumental values should be carefully correlated with a visual appraisal of the acceptability of differences in hue, lig...
SCOPE
1.1 This practice covers the calculation, from instrumentally measured color coordinates based on daylight illumination, of color tolerances and small color differences between opaque specimens such as painted panels, plastic plaques, or textile swatches. Where it is suspected that the specimens may be metameric, that is, possess different spectral curves though visually alike in color, Practice D4086 should be used to verify instrumental results. The tolerances and differences determined by these procedures are expressed in terms of approximately uniform visual color perception in CIE 1976 CIELAB opponent-color space (1),2 CMC tolerance units (2), CIE94 tolerance units (3), the DIN99o color difference formula given in DIN 6176  (4), or the CIEDE2000 color difference units (5).  
1.2 For product specification, the purchaser and the seller shall agree upon the permissible color tolerance between test specimen and reference and the procedure for calculating the color tolerance. Each material and condition of use may require specific color tolerances because other appearance factors, (for example, specimen proximity, gloss, and texture), may affect the correlation between the magnitude of a measured color difference and its commercial acceptability.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-May-2023
• ICS: 17.180.20 - Colours and measurement of light
• Technical Committee: E12 - Color and Appearance
• Drafting Committee: E12.04 - Color and Appearance Analysis

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D2244 − 23
Standard Practice for
Calculation of Color Tolerances and Color Differences from
1
Instrumentally Measured Color Coordinates
This standard is issued under the fixed designation D2244; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
INTRODUCTION
This practice originally resulted from the consolidation of a number of separately published
methods for the instrumental evaluation of color differences. As revised in 1979, it included four color
spaces in which color-scale values could be measured by instruments, many of which were obsolete,
and the color differences calculated by ten equations for different color scales. The sections on
apparatus, calibration standards and methods, and measurement procedures served little purpose in the
light of modern color-measurement technology. The revision published in 1993 omitted these sections,
and limited the color spaces and color-difference equations considered, to the three most widely used
in the paint and related coatings industry. A previous revision added two new color tolerance equations
and put one of the color difference equations from the 1993 version in an informative appendix for
historical purposes.
1. Scope the correlation between the magnitude of a measured color
difference and its commercial acceptability.
1.1 This practice covers the calculation, from instrumentally
1.3 This standard does not purport to address all of the
measured color coordinates based on daylight illumination, of
safety concerns, if any, associated with its use. It is the
color tolerances and small color differences between opaque
responsibility of the user of this standard to establish appro-
specimens such as painted panels, plastic plaques, or textile
priate safety, health, and environmental practices and deter-
swatches. Where it is suspected that the specimens may be
mine the applicability of regulatory limitations prior to use.
metameric, that is, possess different spectral curves though
1.4 This international standard was developed in accor-
visually alike in color, Practice D4086 should be used to verify
dance with internationally recognized principles on standard-
instrumental results. The tolerances and differences determined
ization established in the Decision on Principles for the
by these procedures are expressed in terms of approximately
Development of International Standards, Guides and Recom-
uniform visual color perception in CIE 1976 CIELAB
2
mendations issued by the World Trade Organization Technical
opponent-color space (1), CMC tolerance units (2), CIE94
Barriers to Trade (TBT) Committee.
tolerance units (3), the DIN99o color difference formula given
in DIN 6176 (4), or the CIEDE2000 color difference units (5).
2. Referenced Documents
1.2 For product specification, the purchaser and the seller
3
2.1 ASTM Standards:
shall agree upon the permissible color tolerance between test
D1729 Practice for Visual Appraisal of Colors and Color
specimen and reference and the procedure for calculating the
Differences of Diffusely-Illuminated Opaque Materials
color tolerance. Each material and condition of use may require
D4086 Practice for Visual Evaluation of Metamerism
specific color tolerances because other appearance factors, (for
E284 Terminology of Appearance
example, specimen proximity, gloss, and texture), may affect
E308 Practice for Computing the Colors of Objects by Using
the CIE System
1
This practice is under the jurisdiction of ASTM Committee E12 on Color and
E805 Practice for Identification of Instrumental Methods of
Appearance and is the direct responsibility of Subcommittee E12.04 on Color and
Appearance Analysis.
Current edition approved June 1, 2023. Published June 2023. Originally
3
approved in 1964. Last previous edition approved in 2022 as D2244 – 22. DOI: For referenced ASTM standards, visit the ASTM website, www.astm.org, or
10.1520/D2244-23. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
2
The boldface numbers in parentheses refer to the list of references at the end of Standards volume information, refer to the standard’s Document Summary page on
this standard. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D224
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This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D2244 − 22 D2244 − 23
Standard Practice for
Calculation of Color Tolerances and Color Differences from
1
Instrumentally Measured Color Coordinates
This standard is issued under the fixed designation D2244; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
INTRODUCTION
This practice originally resulted from the consolidation of a number of separately published
methods for the instrumental evaluation of color differences. As revised in 1979, it included four color
spaces in which color-scale values could be measured by instruments, many of which were obsolete,
and the color differences calculated by ten equations for different color scales. The sections on
apparatus, calibration standards and methods, and measurement procedures served little purpose in the
light of modern color-measurement technology. The revision published in 1993 omitted these sections,
and limited the color spaces and color-difference equations considered, to the three most widely used
in the paint and related coatings industry. A previous revision added two new color tolerance equations
and put one of the color difference equations from the 1993 version in an informative appendix for
historical purposes.
1. Scope
1.1 This practice covers the calculation, from instrumentally measured color coordinates based on daylight illumination, of color
tolerances and small color differences between opaque specimens such as painted panels, plastic plaques, or textile swatches.
Where it is suspected that the specimens may be metameric, that is, possess different spectral curves though visually alike in color,
Practice D4086 should be used to verify instrumental results. The tolerances and differences determined by these procedures are
2
expressed in terms of approximately uniform visual color perception in CIE 1976 CIELAB opponent-color space (1), CMC
tolerance units (2), CIE94 tolerance units (3), the DIN99o color difference formula given in DIN 6176 (4), or the CIEDE2000 color
difference units (5).
1.2 For product specification, the purchaser and the seller shall agree upon the permissible color tolerance between test specimen
and reference and the procedure for calculating the color tolerance. Each material and condition of use may require specific color
tolerances because other appearance factors, (for example, specimen proximity, gloss, and texture), may affect the correlation
between the magnitude of a measured color difference and its commercial acceptability.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1
This practice is under the jurisdiction of ASTM Committee E12 on Color and Appearance and is the direct responsibility of Subcommittee E12.04 on Color and
Appearance Analysis.
Current edition approved Oct. 1, 2022June 1, 2023. Published October 2022June 2023. Originally approved in 1964. Last previous edition approved in 20212022 as
D2244 – 21.D2244 – 22. DOI: 10.1520/D2244-22.10.1520/D2244-23.
2
The boldface numbers in parentheses refer to the list of references at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D2244 − 23
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
3
2.1 ASTM Standards:
D1729 Practice for Visual Appraisal of Colors and Color Differences of Diffusely-Illuminated Opaque Materials
D4086 Practice for Visual Evaluation of Metamerism
E284 Terminology of Appearance
E308 Practice for Computing the Colors of Objects by Using the CIE System
E805 Practice for Identification of Instrumental Methods of Color or Color-Difference Measurement of Materials
E1164 Pra
...