ASTM E1360-05(2019)
(Practice)Standard Practice for Specifying Color by Using the Optical Society of America Uniform Color Scales System
Standard Practice for Specifying Color by Using the Optical Society of America Uniform Color Scales System
SIGNIFICANCE AND USE
5.1 Notational systems that specify and identify colors have proved to be very useful. This practice describes how to assign an OSA-UCS notation to a color specimen. This notation gives its position within the color space determined by the Optical Society of America Committee on Uniform Color Scales to represent the closest possible approximation to a color space in which equal distances equate to equal visually perceived differences. The cuboctahedral sampling fills the color space with a more closely spaced set of samples than would a cubic lattice or samples placed on polar coordinates.
SCOPE
1.1 This practice provides a means for specifying the colors of objects in terms of the Optical Society of America Uniform Color Scales. Both computational and visual methods are included. The practice is limited to opaque objects, such as painted surfaces, viewed in daylight by an observer having normal color vision.
1.2 This practice does not cover the preparation of specimens. If the preparation of specimens is required in conjunction with this practice, a mutually agreed upon procedure shall be established.
1.3 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
Relations
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: E1360 − 05 (Reapproved 2019)
Standard Practice for
Specifying Color by Using the Optical Society of America
Uniform Color Scales System
This standard is issued under the fixed designation E1360; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
TheOpticalSocietyofAmericaUniformColorScales(OSA-UCS)weredevelopedbyacommittee
oftheOpticalSocietyofAmericaintheyearsbetween1947and1974inanefforttoprovideasystem
andasetofsamplesthatrepresenttheclosestpossibleapproximationtoequalvisualspacing (1). The
system is defined by a set of equations derived from the results of visual scaling experiments and
related to the 1964 CIE system. The OSA sample set consisted of 558 atlas samples that fell at the
lattice points of a rhombohedral close-packed arrangement within the color space defined by the
equations. The unit in this spacing is a cuboctahedron, each color being surrounded by twelve
equidistant nearest neighbors. See Fig. 1 and Fig. 2. Fig. 3 shows a OSA-UCS lightness plane plotted
on the CIE 1964 chromaticity diagram. The OSA-UCS system is described in Appendix X1.
The system is independent of the OSA-UCS atlas samples, and other groups of samples could be
chosenwithinthedefinedcolorspace;however,forthevisualdeterminationofcolorsdescribedinthis
standard, the OSA set of samples is used.
1. Scope 2. Referenced Documents
2.1 ASTM Standards:
1.1 This practice provides a means for specifying the colors
D1535Practice for Specifying Color by the Munsell System
of objects in terms of the Optical Society ofAmerica Uniform
D1729Practice for Visual Appraisal of Colors and Color
Color Scales. Both computational and visual methods are
Differences of Diffusely-Illuminated Opaque Materials
included. The practice is limited to opaque objects, such as
E284Terminology of Appearance
painted surfaces, viewed in daylight by an observer having
E308PracticeforComputingtheColorsofObjectsbyUsing
normal color vision.
the CIE System
1.2 This practice does not cover the preparation of speci-
E1164PracticeforObtainingSpectrometricDataforObject-
mens. If the preparation of specimens is required in conjunc-
Color Evaluation
tion with this practice, a mutually agreed upon procedure shall
be established. 3. Terminology
3.1 Definitions of Terms Specific to This Standard:
1.3 This international standard was developed in accor-
3.1.1 chromaticness, n—an attribute of a visual sensation
dance with internationally recognized principles on standard-
combining hue and chroma; the visual correlate of the colori-
ization established in the Decision on Principles for the
metric quantity chomaticity.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
3.1.2 hue, n—the attribute of color perception by means of
Barriers to Trade (TBT) Committee.
which an object is judged to be red, yellow, green, blue, or
intermediate between some adjacent pair of these. In the
OSA-UCS system each hue is denoted by its angle within a
360° circle beginning in the yellow direction on the right hand
This practice is under the jurisdiction ofASTM Committee E12 on Color and
AppearanceandisthedirectresponsibilityofSubcommitteeE12.07onColorOrder
Systems.
Current edition approved Nov. 1, 2019. Published November 2019. Originally
approved in 1990. Last previous edition approved in 2015 as E1360–05 (2015). For referenced ASTM standards, visit the ASTM website, www.astm.org, or
DOI: 10.1520/E1360-05R19. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
The boldface numbers in parentheses refer to a list of references at the end of Standards volume information, refer to the standard’s Document Summary page on
this practice. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1360 − 05 (2019)
NOTE 1—Cuboctahedron showing location of L, j, and g axes through
its center and the locations and L, j, g coordinates of the center point and
its12nearestneighbors.ThelatticeoftheOSA-UCSsystemisderivedby
extending this unit in all directions to the extremes of color space. In this
NOTE 1—CIE 1964 (x , y )-chromaticity diagram showing chroma-
drawing horizontal nearest-neighbor planes are emphasized with heavy 10 10
ticitypoints(j,g)ofcolorsofOSAColorSystemforlightnesslevelL=0.
lines.FromBillmeyer,F.W.,Jr.,“SurveyofColorOrderSystems,” Color
The chromaticity point N is that of the nominal gray (D ) in the system.
Research and Application, Vol 12, (2). Copyright 1987, John Wiley & 65
From Wyszecki, G., and Stiles, W. S., Color Science, 2nd ed., (3).
Sons.
Copyright 1982, John Wiley & Sons.
FIG. 1 Cuboctahedron Showing Axes and Horizontal Planes
FIG. 3 OSA L = O Plane on the CIE 1964 Chromaticity Diagram
redness are used throughout this practice for convenience. However, this
does not imply that the j and g axes indicate the locations of the
corresponding unitary hues: The+j axis closely approximates the direc-
tion toward unitary yellow; but the+g axis divides the green and blue
regions, the−j axis divides the blue and purple regions, and the−g axis
locates pinks and magentas. It is probably best to think of j and g as
abstract symbols unassociated with color names (4).
3.1.4 OSA-UCS samples, n—the Optical Society of Ameri-
ca’s physical exemplification of the OSA-UCS color system,
which consisted of 558 samples displayed in a face-centered
lattice in three-dimensional space such that each interior
samplehas12nearestneighborsatequalintervalsfromit.This
configuration is sometimes referred to as a cuboctahedral or
rhombohedral lattice.
NOTE 1—Cuboctahedron of Fig. 1 showing a typical vertical plane ()
and a typical oblique plane (.) containing nearest-neighbor colors.
3.2 Definitions:
From Billmeyer, F. W., Jr., “Survey of Color Order Systems,” Color
3.2.1 The definitions in Practice D1535 and Terminology
Research and Application, Vol 12, (2). Copyright 1987, John Wiley &
E284 are applicable to this practice.
Sons.
FIG. 2 Cuboctahedron Showing Vertical and Oblique Planes
4. Summary of Practice
4.1 Computation Method—CIE 1964 tristimulus values for
sideofthehuecircleandproceedingcounterclockwisethrough
standard illuminant D and the 1964 supplementary (10°)
the greens, blues, and reds to return to the yellow hue, 360, on
standard observer are obtained from spectrophotometric or
the+j axis.
colorimetric measurements. See Practice E308 and Practice
3.1.3 OSA-UCS color system, n—Optical Society of
E1164. Transformation equations (5) from CIE 1964 tristimu-
America Uniform Color Scales color order system based on
lus values to OSA-UCS notations are given in Section 7, and
equality of visual spacing, which uses the lightness scale 6L
the OSA-UCS notations and CIE specifications of the OSA
and the opponent-color scales 6j(yellowness-blueness) and 6
atlas samples are given in Table 1.
g(greenness-redness).Acolor in the OSA-UCS system may be
4.2 Visual Method—Observers must have normal color
describedbyitsL,j,gnotationorbyitslightness,L;hueangle,
vision. Specimens should be viewed on an essentially nonse-
h , and chroma, c , designation.
OSA OSA
lectivegraybackgroundof30%luminousreflectance,equiva-
NOTE 1—The conventional terms yellowness, greenness, blueness, and lent to the OSA-UCS notationL=0,j=0,g=0, abbreviated
E1360 − 05 (2019)
TABLE 1 CIE Specification for OSA-UCS Notations
OSA Lattice Coordinates CIE Specifications OSA Lattice Coordinates CIE Specifications
L jg Y x y L jg Y x y
10 10 10 10 10 10
A: Full-Step Colors A: Full-Step Colors
−7 −3 −1 3.22 0.2588 0.2169 0 −6 10.29 0.4236 0.2940
−3 1 3.24 0.2152 0.2251 0 −4 10.83 0.3875 0.3053
0 −2 11.25 0.3511 0.3176
−1 −1 3.54 0.3113 0.2841 0 0 11.53 0.3139 0.3309
−1 1 3.59 0.2569 0.3002 0 2 11.61 0.2756 0.3455
0 4 11.45 0.2357 0.3617
1 −1 3.79 0.3783 0.3571
1 1 3.92 0.3147 0.3858 2 −8 9.49 0.5132 0.3159
2 −6 10.27 0.4751 0.3304
−6 −4 −2 4.85 0.2656 0.2044 2 −4 11.00 0.4363 0.3461
−4 0 4.89 0.2304 0.2101 2 −2 11.62 0.3968 0.3631
−4 2 4.88 0.1960 0.2164 2 0 12.04 0.3564 0.3816
2 2 12.18 0.3145 0.4023
−2 −4 5.05 0.3508 0.2471 2 4 11.97 0.2699 0.4262
−2 −2 5.22 0.3090 0.2565
−2 0 5.32 0.2665 0.2670 4 −8 9.06 0.5677 0.3432
−2 2 5.32 0.2239 0.2783 4 −6 9.97 0.5289 0.3627
4 −4 10.89 0.4883 0.3837
0 −6 4.85 0.4574 0.2841 4 −2 11.70 0.4466 0.4063
0 −4 5.24 0.4103 0.2981 4 0 12.29 0.4038 0.4310
0 −2 5.56 0.3626 0.3136 4 2 12.52 0.3592 0.4590
0 0 5.75 0.3139 0.3309 4 4 12.29 0.3110 0.4927
0 2 5.78 0.2632 0.3505
−3 −5 −1 13.44 0.2529 0.2238
2 −6 5.00 0.5240 0.3260 −5 1 13.48 0.2276 0.2287
2 −4 5.24 0.4774 0.3475 −5 3 13.45 0.2025 0.2339
2 −2 5.73 0.4249 0.3710
2 0 6.06 0.3709 0.3974 −3 −5 13.71 0.3372 0.2488
2 2 6.13 0.3139 0.4283 −3 −3 14.01 0.3088 0.2552
−3 −1 14.21 0.2802 0.2621
−5 −5 −1 6.97 0.2402 0.1997 −3 1 14.30 0.2515 0.2694
−5 1 6.99 0.2114 0.2044 −3 3 14.27 0.2224 0.2772
−5 3 6.96 0.1829 0.2095 −3 5 14.11 0.1930 0.2855
−3 −3 7.35 0.3069 0.2380 −1 −7 13.63 0.4063 0.2760
−3 −1 7.48 0.2723 0.2454 −1 −5 14.18 0.3754 0.2845
−3 1 7.52 0.2375 0.2533 −1 −3 14.64 0.3442 0.2937
−3 3 7.48 0.2027 0.2619 −1 −1 14.97 0.3126 0.3035
−1 1 15.14 0.2805 0.3140
−1 −5 7.42 0.3907 0.2740 −1 3 15.12 0.2476 0.3254
−1 −3 7.76 0.3516 0.2848 −1 5 14.89 0.2136 0.3377
−1 −1 8.00 0.3122 0.2965
−1 1 8.10 0.2720 0.3093 1 −9 12.89 0.4840 0.2981
−1 3 8.05 0.2305 0.3233 1 −7 13.71 0.4510 0.3089
1 −5 14.47 0.4176 0.3206
1 −7 6.95 0.4886 0.3026 1 −3 15.13 0.3839 0.3329
1 −5 7.53 0.4463 0.3171 1 −1 15.62 0.3496 0.3465
1 −3 8.04 0.4034 0.3329 1 1 15.90 0.3146 0.3609
1 −1 8.43 0.3596 0.3503 1 3 15.90 0.2782 0.3771
1 1 8.62 0.3147 0.3695 1 5 15.57 0.2397 0.3950
1 3 8.56 0.2670 0.3916
3 −9 12.53 0.5328 0.3256
3 −7 6.67 0.5505 0.3363 3 −7 13.53 0.4984 0.3399
3 −5 7.39 0.5063 0.3568 3 −5 14.50 0.4631 0.3553
3 −3 8.08 0.4604 0.3791 3 −3 15.37 0.4272 0.3717
3 −1 8.65 0.4132 0.4035 3 −1 16.05 0.3906 0.3893
3 1 8.96 0.3646 0.4307 3 1 16.46 0.3581 0.4087
3 3 8.89 0.3127 0.4631 3 3 16.49 0.3139 0.4305
3 5 16.03 0.2716 0.4561
−4 −4 −2 10.12 0.2758 0.2303
−4 0 10.20 0.2465 0.2362 5 −7 13.07 0.5465 0.3666
−4 2 10.21 0.2172 0.2425 5 −5 14.21 0.5104 0.3863
−4 4 10.13 0.1881 0.2492 5 −3 15.28 0.4732 0.4073
5 −1 16.17 0.4349 0.4299
−2 −4 10.45 0.3435 0.2642 5 1 16.72 0.3956 0.4548
−2 −2 10.72 0.3104 0.2726 5 3 16.78 0.3543 0.4837
−2 0 10.88 0.2770 0.2818 5 5 16.20 0.3092 0.5189
−2 2 10.91 0.2430 0.2914
−2 4 10.80 0.2084 0.3022
A: Full-Step Colors A: Full-Step Colors
−2 −6 0 17.31 0.2354 0.2183 1 −9 22.22 0.4541 0.3038
−6 2 17.31 0.2133 0.2225 1 −7 23.26 0.4268 0.3129
1 −5 24.20 0.3993 0.3226
E1360 − 05 (2019)
TABLE 1 Continued
OSA Lattice Coordinates CIE Specifications OSA Lattice Coordinates CIE Specifications
L jg Y x y L jg Y x y
10 10 10 10 10 10
−4 −2 18.10 0.2824 0.2474 1 −3 25.00 0.3714 0.3330
−4 0 18.23 0.2574 0.2531 1 −1 25.60 0.3432 0.3439
−4 2 18.26 0.2323 0.2591 1 1 25.96 0.3145 0.3555
−4 4 18.18 0.2071 0.2655 1 3 26.02 0.2849 0.3682
1 5 25.75 0.2541 0.3820
−2 −6 18.09 0.3658 0.2683
−2 −4 18.58 0.3386 0.2754 3 −9 21.97 0.4933 0.3291
−2 −2 18.96 0.3112 0.2829 3 −7 23.24 0.4646 0.3408
−2 0 19.19 0.2836 0.2910 3 −5 24.42 0.4357 0.3529
−2 2 19.27 0.2555 0.2995 3 −3 25.46 0.4063 0.3659
−2 4 19.16 0.2268 0.3086 3 −1 26.26 0.3764 0.3797
−2 6 18.87 0.1977 0.3182 3 1 26.77 0.3459 0.3946
3 3 26.89 0.3144 0.4109
0 −10 16.86 0.4609 0.2831 3 5 26.54 0.2812 0.4292
0 −8 17.71 0.4320 0.2914
0 −6 18.50 0.4029 0.3004 5 −9 21.43 0.5332 0.3520
0 −4 19.19 0.3736 0.3099 5 −7 22.89 0.5039 0.3664
0 −2 19.73 0.3440 0.3200 5 −5 24.31 0.4738 0.3815
0 0 20.10 0.3139 0.3309 5 −3 25.58 0.4432 0.3975
0 2 20.24 0.2831 0.3426 5 −1 26.60 0.4119 0.4146
0 4 20.12 0.2512 0.3553 5 1 27.26 0.3801 0.4330
0 6 19.71 0.2180 0.3692 5 3 27.45 0.3470 0.4535
5 5 27.01 0.3119 0.4773
2 −10 16.59 0.5043 0.3094
2 −8 17.65 0.4739 0.3203 7 −9 20.62 0.5724 0.3707
2 −6 18.66 0.4430 0.3320 7 −7 22.22 0.5431 0.3883
2 −4 19.57 0.4118 0.3443 7 −5 23.82 0.5127 0.4067
2 −2 20.32 0.3801 0.3577 7 −3 25.31 0.4814 0.4261
2 0 20.84 0.3479 0.3719 7 −1 26.55 0.4493 0.4468
2 2 21.07 0.3147 0.3874 7 1 27.38 0.4165 0.4694
2 4 20.93 0.2800 0.4046 7 3 27.63 0.3823 0.4948
2 6 20.35 0.2430 0.4243 7 5 27.09 0.3460 0.5249
4 −10 16.06 0.5486 0.3328 0 −6 0 26.50 0.2457 0.2349
4 −8 17.28 0.5175 0.3468 −6 2 26.52 0.2260 0.2391
4 −6 18.50 0.4853 0.3618
4 −4 19.64 0.4525 0.3775 −4 −2 27.49 0.2872 0.2598
4 −2 20.61 0.4192 0.3942 −4 0 27.68 0.2655 0.2652
4 0 21.32 0.3851 0.4124 −4 2 27.75 0.2437 0.2708
4 2 22.65 0.3500 0.4324 −4 4 27.68 0.2217 0.2767
4 4 21.49 0.3130 0.4551
−2 −4 28.12 0.3350 0.2835
6 −10 15.33 0.5915 0.3515 −2 −2 28.58 0.3118 0.2903
6 −8 18.65 0.5608 0.3691 −2 0 28.88 0.2883 0.2974
6 −6 18.02 0.5283 0.3877 −2 2 29.00 0.2644 0.3049
6 −4 19.36 0.4948 0.4072 −2 4 28.93 0.2401 0.3128
6 −2 20.55 0.4603 0.4282
6 0 21.45 0.4250 0.4508 0 −8 27.22 0.4130 0.2972
6 2 21.89 0.3885 0.4758 0 −6 28.14 0.3886 0.3050
6 4 21.91 0.3498 0.5046 0 −4 28.93 0.3640 0.3131
0 −2 29.57 0.3391 0.3218
−1 −5 −1 22.61 0.2618 0.2405 0 0 30.00 0.3138 0.3310
−5 1 22.69 0.2397 0.2454 0 2 30.20 0.2882 0.3406
−5 3 22.66 0.2176 0.2504 0 4 30.13 0.2617 0.3511
0 6 29.77 0.2345 0.3622
−3 −3 23.36 0.3099 0.2670
−3 −1 23.67 0.2856 0.2734 2 −8 27.35 0.4469 0.3230
−3 1 23.81 0.2612 0.2801 2 −6 28.50 0.4212 0.3327
−3 3 23.81 0.2364 0.2871 2 −4 29.52 0.3951 0.3429
−3 5 23.64 0.2113 0.2945 2 −2 30.36 0.3688 0.3537
2 0 30.95 0.3421 0.3652
−1 −7 22.97 0.3911 0.2841 2 2 31.25 0.3147 0.3775
−1 −5 23.68 0.3652 0.2917 2 4 31.19 0.2863 0.3909
−1 −3 24.27 0.3392 0.2996 2 6 30.73 0.2567 0.4056
−1 −1 24.70 0.3129 0.3081
−1 1 24.94 0.2861 0.3171 4 −8 27.16 0.4824 0.3475
−1 3 24.96 0.2588 0.3266
−1 5 24.74 0.2308 0.3369
A: Full-Step Colors A: Full-Step Colors
4 −6 28.55 0.4555 0.3594 9 −7 31.66 0.5387 0.4045
4 −4 29.81 0.4283 0.3719 9 −5 33.55 0.5126 0.4214
4 −2 30.87 0.4007 0.3852 9 −3 35.29 0.4858 0.4389
4 0 31.64 0.3726 0.3993 9 −1 36.76 0.4585 0.4578
4 2 32.05 0.3438 0.4146 9 1 37.79 0.4305 0.4780
E1360 − 05 (2019)
TABLE 1 Continued
OSA Lattice Coordinates CIE Specifications OSA Lattice Coordinates CIE Specifications
L jg Y x y L jg Y x y
10 10 10 10 10 10
4 4 32.01 0.3139 0.4315 9 3 38.24 0.4017 0.5003
4 6 31.42 0.2822 0.4506
2 −4 0 39.65
...
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