1、Designation: D1729 96 (Reapproved 2009)D1729 16Standard Practice forVisual Appraisal of Colors and Color Differences ofDiffusely-Illuminated Opaque Materials1This standard is issued under the fixed designation D1729; the number immediately following the designation indicates the year oforiginal adop
2、tion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript 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 Defens
3、e.INTRODUCTIONThe colors of materials depend on the geometric and spectral nature of the illuminating and viewingconditions. This practice specifies standard conditions for appraising the colors and color differencesof opaque specimens that are diffusely illuminated. Daylight, the natural illuminant
4、, is usually ofprimary interest, but natural daylight is highly variable and is not available at night or in interiorrooms, so simulated daylight is generally used. Colors may match under a light source with onespectral power distribution, but not under another, so the match is usually confirmed und
5、er anothervery different source. An incandescent lamp of low correlated color temperature has long been usedto detect mismatches likely to appear under yellower phases of daylight or incandescent light.Industrial color matchers often verify the match with the kind of light likely to be found where t
6、heproduct is sold or used. Judgments mustshould be made by observers with normal color vision.superior color vision as rated with the FM-100 Hue Test. Even so, there may be substantial individualdifferences in judgments.1. Scope1.1 This practice specifies the equipment and procedures for visual appr
7、aisal of the colors and color differences of opaquematerials that are diffusely illuminated. These specificationspecifications are of critical importance in color matching. This practicerequires judgments by observers with normal color vision.a minimum of normal color vision and preferably superior
8、as rated withthe FM-100 Hue Test as specified in Guide E1499.1.2 Critical visual appraisal of colors and color differences of materials such as metallic and pearlescent paints requiresillumination that is nearly a geometric simulation of direct sunlight, because such directional illumination permits
9、 observation ofthe glitter sparkle (glitter) and goniochromatism that characterize such materials. Such viewing conditions are beyond the scopeof this practice.1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.4 This stan
10、dard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 AST
11、M Standards:2D523 Test Method for Specular GlossD1535 Practice for Specifying Color by the Munsell SystemD4086 Practice for Visual Evaluation of Metamerism1 This practice is under the jurisdiction of ASTM Committee E12 on Color and Appearance and is the direct responsibility of Subcommittee E12.11 o
12、n Visual Methods.Current edition approved Dec. 1, 2009Jan. 1, 2016. Published December 2009February 2016. Originally approved in 1960. Last previous edition approved in 20032009as D1729 96 (2003).(2009). DOI: 10.1520/D172996R09.10.1520/D1729-16.This standard has been approved for use by agencies of
13、the Department of Defense to replace Method 4249.1 of Federal Test Method Standard No 141. Consult the DoDIndex of Specifications and Standards for the specific year of issue which has been adopted by the Department of Defense.2 For referencedASTM standards, visit theASTM website, www.astm.org, or c
14、ontactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.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
15、been made to the previous version. Becauseit 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 versionof the standard as published by ASTM is to be considered the official docum
16、ent.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D5531 Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and GeometricAppearance of CoatingsE284 Terminology of AppearanceE308 Practice for
17、Computing the Colors of Objects by Using the CIE SystemE1164 Practice for Obtaining Spectrometric Data for Object-Color EvaluationE1499 Guide for Selection, Evaluation, and Training of Observers2.2 ISO/CIE Standard:3ISO 10526 CIE Standard Colorimetric Illuminants (1991)ISO 3664-2009 Graphic Technolo
18、gy and photographyViewing conditions3. Terminology3.1 For definitions of appearance terms used in this practice, refer to Terminology E284.4. Significance and Use4.1 Although color measuring instruments are widely used, color matches are usually checked visually. The standardization ofvisual examina
19、tion has greatly improved the uniformity of products and the accuracy of color matches.4.2 The use of this practice is essential for critical color matching but is also recommended for any color appraisal, such as thechoice or approval of a color. This practice is widely used in industry to choose c
20、olors, exhibit colors reproducibly,reproducibility,inspect incoming materials, monitor color producing processes, and inspect finished goods. Visual appraisal is particularlyimportant when the product inspected is not of the same material as the color standard to which it is compared.4.2.1 Observers
21、This practice is based on the fundamental assumption that the observer has normalsuperior color vision andis trained and experienced in observing and classifying color differences. The significance of the results depends on that being so.The selection, evaluation, and training of observers are treat
22、ed in Guide E1499.4.2.2 IlluminationSimulated average daylight daylight, D65, is recommended by the International Commission onIllumination (CIE), but a slightly bluer simulated north-sky daylight came into widespread use in North America, because itprovides a slightly greater distinction between ve
23、ry pale yellow and white, a distinction of great commercial importance.(CIE).D50 is recommended for applications involving color photography or color printing as specified in ISO 3364-2009.5. Observers5.1 The validity of the results obtained by this practice depends on visual judgments by an observe
24、r or observers withnormalhaving superior color vision. Even among normal observers, there may be substantial individual variations. Colorspecifications dependent on this practice may require averaging the results obtained by a specified number of observers. The natureof an observers color vision can
25、 be ascertained by visual tests. Observers should be tested periodically, because an individualscolor vision can change (see Guide E1499).6. Apparatus6.1 The apparatus shall consist of luminaires, luminaires or viewing booth, specimen table, surround, and ambient field havingthe following spectral,
26、photometric, and geometric characteristics:6.1.1 Spectral Power DistributionThe spectral power distribution of the radiant flux incident on the specimens depends notonly on the source used, but on the nature of any diffuser employed and any reflecting surfaces, including those in the ambientfield, t
27、hat reflect flux to the specimens.6.1.1.1 Daylight illumination shall be a spectral simulation of daylight of one or more of the following three kinds: overcastnorthern sky light, designated CIE Illuminant two kinds: D75; average daylight, designated CIE Illuminant D65; or, for applicationsinvolving
28、 color photography or color printing, CIE Illuminant D50. The spectra of these illuminants are specified in Practice E308and CIE Publication 15.2.15:2004.4 The quality of the simulation of daylight shall be assessed by the method specified in the latestrevision of CIE Publication 51ISO/CIE 23603:200
29、5, previously designated as Publication 51.5 (under revision in 1996). For criticalappraisal of colors and color differences, the category determined by that method shall be BC(CIELAB) or better. This ratingensures that the source provides ultraviolet and visible power in the right proportions to ma
30、ke both nonfluorescent and fluorescentmaterials look very nearly the way they would in the corresponding phase of natural daylight. Users of this practice should beaware of the fact that neither correlated color temperature nor chromaticity alone qualifies simulated daylight for this purpose.6.1.1.2
31、 Incandescent illumination shall have the spectral quality of the light from an incandescent lamp commonly used forhome and business lighting, approximately simulating CIE Illuminant A, specified in Practice E308 and ISO/CIE 10526.3 Available from U.S. National Committee of the CIE (International Co
32、mmission on Illumination), C/o Thomas M. Lemons, TLA-Lighting Consultants, Inc., 7 Pond St.,Salem, MA 01970, http:/www.cie-usnc.org.4 CIE Publication 15.215:2004, Colorimetry, 2nd3rd ed., Central Bureau of the CIE, Vienna, 19862004 (see footnote 3).5 CIE Publication 51, ISO/CIE 23603:2005, A Method
33、for Assessing the Quality of Daylight Simulators for Colorimetry, Central Bureau of the CIE, Vienna, 1981(seefootnote 3).D1729 1626.1.1.3 Incandescent illumination of low correlated color temperature shall have spectral quality similar to that of a Planckianradiator having a color temperature of 230
34、0 K. This source is referred to as “Horizon Daylight” because it simulates the spectraof early morning sunrise and late day sunset. This light is commonly produced by incandescent lamps operated at half their ratedvoltage.66.1.1.4 Fluorescent lamps are often provided. Those most often used are of th
35、e type known as “cool white” approximatelysimulated by simulating CIE Illuminant F2, and the type known as “three-band” approximately simulated by simulating CIEIlluminant F11. F11 and F12. The spectra of these illuminants are specified in Practice E308 and ISO/CIE 10526. Recently, dueto energy legi
36、slation, lamps simulating CIE Illuminant F2 have been limited to smaller sizes as used in specialty applianceapplications.6.1.1.5 One or several of these kinds of illumination, or other kinds, as specified, may be provided in a luminaire or viewingbooth. Provision must be made for selecting any one
37、of the sources independently. The blending of a broadband daylight sourcewith incandescent illumination has shown to be effective in detecting metamerism in some color matching applications.6.1.2 Photometric ConditionsFor critical evaluation of color differences of materials of medium lightness, the
38、 illumination atthe center of the viewed area shall be 1080 to 1340 lx (100 to 125 fc). For general evaluation of materials of medium lightness,the illumination shall be between 810 and 1880 lx (75 and 175 fc). In either case, for viewing very light materials, the illuminationmay be as low as 540 lx
39、 (50 fc), and for viewing very dark materials it may be as high as 2150 lx (200 fc). This higher level ofillumination is usually obtained by holding the specimens nearer the source.6.1.3 Geometric ConditionsThe illumination shall be provided by an extended-area source located above the specimens and
40、shall be sufficiently directional to reveal the texture of specimens. The illuminance shall be uniform over the viewing area, within620 %, with no abrupt changes apparent to the observer.6.1.4 Surround and Ambient FieldThe surround, the portion of the visual field immediately surrounding the specime
41、ns, shallbe the color having the Munsell notation given in Table 1 for the evaluation category involved. The ambient visual field, the fieldof view seen when the observer glances away from the specimens, such as the interior surfaces of a viewing booth or the nearbywalls of a viewing room, shall be
42、the color having the Munsell notation given in Table 1 for the evaluation category involved.6.1.4.1 The gloss of the surround and the ambient field shall be no greater than 15 on the 60 gloss scale described in TestMethod D523.6.1.4.2 When glossy or highly saturated specimens are compared, it is imp
43、ortant to avoid observing light specularly reflectedby them. Black velvet or other matte black material should be placed in the ambient field, so its dark image is reflected by thespecimens.6.2 Availability of Apparatus:6.2.1 Equipment meeting the requirements of this practice is commercially availa
44、ble. The most important requirement, whichis of particular importance for daylight simulators, is the spectral power distribution of the illumination.6.2.2 Commercially available illumination meters may be used to measure the photometric conditions.6.2.3 Paint for the surround and the ambient field
45、may be specified by the Munsell notations given in Table 1.6.2.4 Commercially available spectroradiometers with a measurement range of 300 to 780 nm and having a minimum band-passhalf-width of 5 nm, may be used to measure the spectral power distributions and the CIE method of computation may beaccom
46、plished with a personal computer.6.3 Maintenance of ApparatusLamps and other apparatus must be maintained. At least once during each 100 h of use, checkthe apparatus in the following way:6.3.1 Replace darkened or burned-out lamps in sets and be sure that all lamps are operating.6.3.2 Clean the fixtu
47、res so dust or films deposited from the atmosphere do not alter the spectral power distributions.6.3.3 Measure and record illumination levels.6 The equations describing Planckian radiators and tables of their distributions can be found in Wyszecki, G., and Stiles, W. S., Color Science Concepts and M
48、ethods,Quantitative Data and Formulae, 2nd ed., John Wiley color difference; color matching; lighting; viewing conditions; visual examinationcolor; visual examinationcolor differenceASTM International takes no position respecting the validity of any patent rights asserted in connection with any item
49、 mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive ca
