1、Designation: D1729 96 (Reapproved 2009)Standard 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 adoption or,
2、 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 Department of Defense.INTRODUCTIO
3、NThe 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, is usually
4、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 under anotherver
5、y 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 theproduct is
6、sold or used. Judgments must be made by observers with normal color vision. Even so, theremay be substantial individual differences in judgments.1. Scope1.1 This practice specifies the equipment and procedures forvisual appraisal of the colors and color differences of opaquematerials that are diffus
7、ely illuminated. These specification areof critical importance in color matching. This practice requiresjudgments by observers with normal color vision.1.2 Critical visual appraisal of colors and color differencesof materials such as metallic and pearlescent paints requiresillumination that is nearl
8、y a geometric simulation of sunlight,because such directional illumination permits observation ofthe glitter and goniochromatism that characterize such materi-als. Such viewing conditions are beyond the scope of thispractice.1.3 The values stated in SI units are to be regarded as thestandard. The va
9、lues given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of r
10、egulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D523 Test Method for Specular GlossD1535 Practice for Specifying Color by the Munsell SystemD4086 Practice for Visual Evaluation of MetamerismD5531 Guide for Preparation, Maintenance, and Distribu-tion of Physical Product
11、Standards for Color and Geomet-ric Appearance of CoatingsE284 Terminology of AppearanceE308 Practice for Computing the Colors of Objects byUsing the CIE SystemE1164 Practice for Obtaining Spectrometric Data forObject-Color EvaluationE1499 Guide for Selection, Evaluation, and Training ofObservers2.2
12、ISO/CIE Standard:310526 CIE Standard Colorimetric Illuminants (1991)1This practice is under the jurisdiction of ASTM Committee E12 on Color andAppearance and is the direct responsibility of Subcommittee E12.11 on VisualMethods.Current edition approved Dec. 1, 2009. Published December 2009. Originall
13、yapproved in 1960. Last previous edition approved in 2003 as D1729 96 (2003).DOI: 10.1520/D172996R09.This standard has been approved for use by agencies of the Department ofDefense to replace Method 4249.1 of Federal Test Method Standard No 141.Consult the DoD Index of Specifications and Standards f
14、or the specific year of issuewhich has been adopted by the Department of Defense.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page
15、 onthe ASTM website.3Available from U.S. National Committee of the CIE (International Commissionon Illumination), C/o Thomas M. Lemons, TLA-Lighting Consultants, Inc., 7 PondSt., Salem, MA 01970, http:/www.cie-usnc.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohoc
16、ken, PA 19428-2959, United States.3. 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 standardiza-tion of visual examinati
17、on has greatly improved the uniformityof products and the accuracy of color matches.4.2 The use of this practice is essential for critical colormatching but is also recommended for any color appraisal,such as the choice or approval of a color. This practice iswidely used in industry to choose colors
18、, exhibit colorsreproducibly, inspect incoming materials, monitor color pro-ducing processes, and inspect finished goods. Visual appraisalis particularly important when the product inspected is not ofthe same material as the color standard to which it is compared.4.2.1 ObserversThis practice is base
19、d on the fundamentalassumption that the observer has normal color vision and istrained and experienced in observing and classifying colordifferences. The significance of the results depends on thatbeing so. The selection, evaluation, and training of observersare treated in Guide E1499.4.2.2 Illumina
20、tionSimulated average daylight is recom-mended by the International Commission on Illumination(CIE), but a slightly bluer simulated north-sky daylight cameinto widespread use in North America, because it provides aslightly greater distinction between very pale yellow and white,a distinction of great
21、 commercial importance.5. Observers5.1 The validity of the results obtained by this practicedepends on visual judgments by an observer or observers withnormal color vision. Even among normal observers, there maybe substantial individual variations. Color specifications de-pendent on this practice ma
22、y require averaging the resultsobtained by a specified number of observers. The nature of anobservers color vision can be ascertained by visual tests.Observers should be tested periodically, because an individu-als color vision can change (see Guide E1499).6. Apparatus6.1 The apparatus shall consist
23、 of luminaires, specimentable, surround, and ambient field having the following spec-tral, photometric, and geometric characteristics:6.1.1 Spectral Power DistributionThe spectral power dis-tribution of the radiant flux incident on the specimens dependsnot only on the source used, but on the nature
24、of any diffuseremployed and any reflecting surfaces, including those in theambient field, that reflect flux to the specimens.6.1.1.1 Daylight illumination shall be a spectral simulationof daylight of one or more of the following three kinds:overcast northern sky light, designated CIE Illuminant D75;
25、average daylight, designated CIE Illuminant D65; or, forapplications involving color photography or color printing,CIE Illuminant D50. The spectra of these illuminants arespecified in Practice E308 and CIE Publication 15.2.4Thequality of the simulation of daylight shall be assessed by themethod spec
26、ified in the latest revision of CIE Publication 515(under revision in 1996). For critical appraisal of colors andcolor differences, the category determined by that method shallbe BC(CIELAB) or better. This rating ensures that the sourceprovides ultraviolet and visible power in the right proportionst
27、o make both nonfluorescent and fluorescent materials lookvery nearly the way they would in the corresponding phase ofnatural daylight. Users of this practice should be aware of thefact that neither correlated color temperature nor chromaticityalone qualifies simulated daylight for this purpose.6.1.1
28、.2 Incandescent illumination shall have the spectralquality of the light from an incandescent lamp commonly usedfor home and business lighting, approximately simulating CIEIlluminant A, specified in Practice E308 and ISO/CIE 10526.6.1.1.3 Incandescent illumination of low correlated colortemperature
29、shall have spectral quality similar to that of aPlanckian radiator having a color temperature of 2300 K. Thislight is commonly produced by incandescent lamps operated athalf their rated voltage.66.1.1.4 Fluorescent lamps are often provided. Those mostoften used are of the type known as “cool white”
30、approxi-mately simulated by CIE Illuminant F2, and the type known as“three-band” approximately simulated by CIE Illuminant F11.The spectra of these illuminants are specified in Practice E308and ISO/CIE 10526.6.1.1.5 One or several of these kinds of illumination, orother kinds, as specified, may be p
31、rovided in a luminaire orviewing booth. Provision must be made for selecting any oneof the sources independently.6.1.2 Photometric ConditionsFor critical evaluation ofcolor differences of materials of medium lightness, the illumi-nation at the center of the viewed area shall be 1080 to 1340 lx(100 t
32、o 125 fc). For general evaluation of materials of mediumlightness, the illumination shall be between 810 and 1880 lx(75 and 175 fc). In either case, for viewing very light materials,the illumination may be as low as 540 lx (50 fc), and forviewing very dark materials it may be as high as 2150 lx (200
33、fc). This higher level of illumination is usually obtained byholding the specimens nearer the source.6.1.3 Geometric ConditionsThe illumination shall be pro-vided by an extended-area source located above the specimensand shall be sufficiently directional to reveal the texture ofspecimens. The illumi
34、nance shall be uniform over the viewingarea, within 620 %, with no abrupt changes apparent to theobserver.6.1.4 Surround and Ambient FieldThe surround, the por-tion of the visual field immediately surrounding the specimens,shall be the color having the Munsell notation given in Table 14CIE Publicati
35、on 15.2, Colorimetry, 2nd ed., Central Bureau of the CIE,Vienna, 1986 (see footnote 3).5CIE Publication 51, A Method for Assessing the Quality of DaylightSimulators for Colorimetry, Central Bureau of the CIE, Vienna, 1981 (see footnote3).6The equations describing Planckian radiators and tables of th
36、eir distributionscan be found in Wyszecki , G., and Stiles, W. S., Color Science Concepts andMethods, Quantitative Data and Formulae, 2nd ed., John Wiley color difference; color matching; lighting; view-ing conditions; visual examinationcolor; visualexaminationcolor differenceASTM International take
37、s no position respecting the validity of any patent rights asserted in connection with any item 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 res
38、ponsibility.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 address
39、ed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the
40、 address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D1729 96 (2009)4
