1、Designation: E 1499 97 (Reapproved 2003)Standard Guide forSelection, Evaluation, and Training of Observers1This standard is issued under the fixed designation E 1499; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide describes criteria and tests for selecting,evaluating, and training human visual-sensory observers fortasks in
3、volving the perception and scaling of properties andphenomena relating to appearance.1.2 Examples of tests requiring the use of trained observersinclude but are not limited to those described in the followingASTM standards: on color, Practice D 1535 and PracticeE 1360; on color difference, Practice
4、D 1729 and Test MethodD 2616; on gloss, Test Method D 4449; on metamerism,Practice D 4086; and on setting tolerances, Practice D 3134.1.3 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 esta
5、blish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1535 Practice for Specifying Color by the Munsell Sys-temD 1729 Practice for Visual Appraisal of Colors and ColorDifferences of Diffusel
6、y Illuminated Opaque MaterialsD 2616 Test Method for Evaluation of Visual Color Differ-ence With a Gray ScaleD 3134 Practice for Establishing Color and Gloss Toler-ancesD 4086 Practice for Visual Evaluation of MetamerismD 4449 Test Method for Visual Evaluation of Gloss Differ-ences Between Surfaces
7、of Similar AppearanceE 284 Terminology of AppearanceE 1360 Practice for Specifying Color by Using the OpticalSociety of America Uniform Color Scales System3. Terminology3.1 DefinitionsDefinitions of appearance terms in Termi-nology E 284 are applicable to this guide.3.2 Definitions of Terms Specific
8、 to This Standard:3.2.1 appearance, nin psychophysical studies, perceptionin which the spectral and geometric aspects of a visual stimulusare integrated with its illuminating and viewing environment.3.2.2 observer, none who judges visually, qualitatively orquantitatively, the content of one or more
9、appearance attributesin each member of a set of objects or stimuli.3.2.3 scale, vto assess the content of one or more appear-ance attributes in the members of a set of stimuli.3.2.3.1 DiscussionAlternatively, scales may be deter-mined by assessing the difference in content of an attributewith respec
10、t to the differences in that attribute among themembers of the set.4. Summary of Guide4.1 This guide provides descriptions of techniques and testsfor the selection of candidates for observers for use in visualtesting, for the evaluation of their capabilities in this field, andfor their training to e
11、nhance these capabilities.4.2 Discussion is provided of precautions required for theefficient use of observers in visual tests, including avoidance ofovertaxing the observers and the control of test variables.4.3 Other considerations of test design, including the num-bers of observers and observatio
12、ns required and the precisionof the visual results, are to be covered elsewhere.5. Significance and Use5.1 The term appearance (see 3.2.1) implies the essentialpresence of human visual observations. The results of visualobservation involve not only the step of observing, accom-plished by the eye, bu
13、t also the inseparable step of interpreta-tion in the brain. Instrumental test methods currently cannotduplicate this second step, and therefore can now only approxi-mate, but not fully measure, appearance. Such instrumentalmeasures of appearance properties are useful only to the extentthat they can
14、 be correlated to the results of visual observationsby observers of the appearance phenomena being evaluated.5.2 Almost invariably, too little attention has been paid toensuring that the essential visual observations have been1This guide is under the jurisdiction of ASTM Committee E12 on Color andAp
15、pearance and is the direct responsibility of Subcommittee E12.11 on VisualMethods.Current edition approved Dec. 1, 2003. Published December 2003. Originallyapproved in 1992. Last previous edition approved in 1997 as E 1499 97.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orco
16、ntact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.properly obtained to
17、 provide the basis for correlating visual andinstrumental test results. (The only recent book devoted tovisual measurements (1)3has no index entry for observer.)5.3 This guide provides the means for assessing observers,by outlining the requirements and tests for their selection,evaluation, and train
18、ing. This guide should be useful to allexperimenters designing or using visual test methods to pro-vide either direct results in terms of the observation ofappearance properties, or the experiments correlating suchresults with instrumental measures approximating the sameappearance properties.6. Sele
19、ction and Evaluation of Observers6.1 The process used for selecting observers depends a greatdeal upon the type of experiment being carried out, but shouldessentially evaluate the potential capability of the observer toexecute a series of visual evaluation tasks (2, 3). When thesetasks involve appea
20、rance attributes, color or related spectralphenomena are often among the task subjects, and if insteadgeometric phenomena such as gloss are involved, many of thesame considerations apply. Accordingly, the emphasis in thisguide is upon selecting observers for color-related measure-ments. Thus, observ
21、ers must be screened to rule out those withany color- or task-oriented deficiencies.6.2 Color Vision Tests (4):6.2.1 Pseudoisochromatic PlatesAs a preliminary colorvision test, a pseudoisochromatic-plate test4,5,6should beadministered to the candidate observers. The instructions andscoring technique
22、s supplied by the manufacturer should befollowed. In particular, the illumination level should be keptwell within the photopic range (1000 1x is recommended as aminimum value) and the spectral quality of the illuminatingsource should be near that of north-sky daylight. Failure toidentify correctly t
23、he required number of the plates in the testused should be considered grounds for dismissing the candi-date observer.6.2.2 Color Rule TestWhen the anticipated experimentinvolves observing in the object mode, the candidate observershould be asked to find a (metameric) match on a Color Rule.5A standar
24、d light source should be used, similar to that specifiedin the majority of tests for which the observer is being trained.It should be remembered that normal trichromats will reportmatch points that are dependent on age (5), but any abnormalmatch point should be considered grounds for dismissing thec
25、andidate observer.NOTE 1An abnormal match point may be considered one that fails tofall within the main groupings of observer match points for the lightsource used on either Fig. 3 of Ref (5) or the figure of Ref (6). Note,however, that this criterion is specific to the originalD see 6.3.1.) In the
26、Farnsworth-Munsell 100 HueTest, abnormal color vision is indicated by the observersfailure to place the test chips in correct order. The chips consistof 85 colored papers varying in hue at approximately constantvalue and chroma, and the observers failure is usually by widemargins in one or more limi
27、ted regions of the hue circle. Thepresence of such abnormal results of the test should be groundsfor dismissing the candidate observer.6.3 Visual Acuity and Discrimination TestsHaving deter-mined that the candidate observers have normal color vision, itis next necessary to test their level of discri
28、mination of smalldifferences in color or another appearance attribute of interest.6.3.1 Farnsworth-Munsell 100 Hue TestUse of theFarnsworth-Munsell 100 Hue Test as a color-discriminationtest does not require readministration of the test, but merelyreexamination of the test results. For the purposes
29、of assessingcolor (more precisely, hue) discrimination, the test results areexamined for the presence of an approximately constant butsignificant error level in the arrangement of the test chipsthroughout the hue circle. This may be interpreted as aninability to discriminate the small color differen
30、ces betweenneighboring chips. While a weakness of this type might, forexample, interfere with an observers ability to participate inthreshold scaling experiments, the observer might still becompetent to perform magnitude scaling of larger differencesamong specimens.6.3.2 Triangle TestThis test is pa
31、rt of a series known asthe Japanese Color Aptitude Test.5,9The candidate observersare shown, one at a time, a series of 20 sets of three coloredchips each. In each set, two of the chips are identical and thethird is slightly different in color. The observer is asked toidentify which one is different
32、, the differences being so smallthat there is considerable uncertainty in the judgment. A lowerthan average score in this test indicates that the observer doesnot differentiate small differences well.3The boldface numbers in parentheses refer to the list of references at the end ofthis standard.4The
33、 sole source of supply of the Dvorine Pseudo-Isochromatic Plates, knownto the committee at this time is The Psychological Corp., Harcourt BraceJovanovich, 555 Academic Court, San Antonio, TX 78204.5If you are aware of alternative suppliers, please provide this information toASTM International Headqu
34、arters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.6The sole source of supply of the H-R-R Pseudoisochromatic plates, IshiharaColor-Blindness Tests, known to the committee at this time is Richmond ProductsInc., 1021 S.
35、Rogers Circle, Suite 6, Boco Raton, FL 33484.7D MatchPoint Rule (available 1990 butnot equivalent to the D the nature and level of theillumination; the nature and luminance of the surround; and theabsence of any distraction in the observers field of vision, suchas light reflected from glossy surface
36、s or brightly coloredclothing.10The sole source of supply of the HVC Color Vision Skill Test, known to thecommittee at this time is Lou Graham and Associates, Inc., 1207 Colonial Ave.,Greensboro, NC 27408.E 1499 97 (2003)38.2.1 The optimum levels of illumination for the judgmentof surface colors giv
37、en in Practice D 1729 are far above thosethat can be obtained with video display units and similardevices. This unavoidable difference must be properly takeninto account in the design of the experiments in whichjudgments of colors and color differences generated on suchdisplays are required.8.3 It i
38、s well known (13) that the visual judgment of colordifferences is affected if the state of adaptation of the observ-ers eyes is changed, since the sensitivity of the eye to colordifferences decreases for the colors corresponding to theadapting color. On examination of a color-difference pair underno
39、rmal conditions (unless the pair specimens are unusuallysmall) their mean color is the adapting color, and prolongedviewing can lead to adaptation to that color and a decrease insensitivity to the color difference. It is therefore usual to viewsmall color differences in quick glances, as they tend t
40、o appearless prominent on prolonged viewing.8.4 In the report noted (10), it was also pointed out that thedifferences among stimuli to be scaled can be too large as wellas too small. There appears to be an upper limit to the size ofdifferences that the human visual system can scale, as well asa thre
41、shold, as is well known.9. Precision and Bias9.1 Matters leading to estimations of the precision and biasof visual measurements will depend strongly on the experi-mental design to be used, but should be explored and consid-ered as an integral part of establishing that design. References(1-12) provid
42、e few examples in which this has been done.10. Keywords10.1 appearance; observers; training; visualexamination-colorREFERENCES(1) Bartleson, C. J., and Grum, F., eds.,“Visual Measurements,” Vol 5 inGrum, F., and Bartleson, C. J., eds., Optical Radiation Measurements,Academic Press, New York, NY, 198
43、4.(2) Taylor, J. M., and Billmeyer, F. W., Jr., “Multidimensional Scaling ofSelected Samples from the Optical Society of America Uniform ColorScales,” Color Research and Application, Vol 13, 1988, pp. 8598.(3) Billmeyer, F. W., Jr., and ODonnell, F. X. D.,“Visual Gloss Scalingand Multidimensional Sc
44、aling Analysis of Painted Specimens,” ColorResearch and Application, Vol 12, 1987, pp. 315326.(4) Procedures for Testing Color Vision, Document No. ADA 113680,National Technical Information Service, U.S. Department of Com-merce, Springfield, VA, 1981.(5) Kaiser, P. K., and Hemmendinger, H., “The Col
45、or Rule, a Device forColor Vision Testing,” Color Research and Application, Vol 5, 1980,pp. 6571.(6) Billmeyer, F. W., Jr., and Saltzman, M., “Observer Metamerism,”Color Research and Application, Vol 5, 1980, p. 72.(7) Farnsworth, D., “The Farnsworth-Munsell 100 Hue and DichotomousTests for Color Vi
46、sion,” Journal of the Optical Society of America,Vol33, 1943, pp. 568578.(8) Lodge, M., “Magnitude Scaling: Quantitative Measurement of Opin-ions,” Sage, Beverly Hills, CA, 1981, p. 9.(9) Strocka, D., Brockes, A., and Paffhausen, W., “Influence of Experi-mental Parameters in the Evaluation of Color-
47、Difference Ellipsoids,”Color Research and Application, Vol 8, 1983, pp. 169175.(10) Billmeyer, F. W., Jr., “1989 ISCC Williamsburg Conference on ColorDiscrimination Psychophysics,” ISCC Technical Report 90-1, ISCC,Princeton, NJ, 1990.(11) Manual on Sensory Testing Methods, ASTM STP 434, ASTM, 1968,S
48、ection I B.(12) Witt, K., “Three-Dimensional Threshold of Color-Difference Percep-tibility in Painted Samples: Variability of Observers in Four CIERegions,” Color Research and Application, Vol 12, 1987, pp.128134.(13) Evans, R. M., “An Introduction to Color,” Wiley, New York, NY,1948, p. 223.ASTM In
49、ternational takes 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 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
