CopyrightInternationalCommissiononIlluminationProvidedbyIHSunderlicensewithCIE

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ISBN3901906339

COLORIMETRY

CIE15:2004

3rdEdition

UDC:

535.66

Descriptor:

Colorimetry

535.67

Colourofobjects

612.843.31

Colourvision

159.937.51

Perceptionofcolour

THEINTERNATIONALCOMMISSIONONILLUMINATION

TheInternationalCommissiononIllumination(CIE)isanorganisationdevotedtointernationalco-operationandexchangeofinformationamongitsmembercountriesonallmattersrelatingtotheartandscienceoflighting.ItsmembershipconsistsoftheNationalCommitteesin38countriesandonegeographicalareaandof4associatemembers.

TheobjectivesoftheCIEare:

Toprovideaninternationalforumforthediscussionofallmattersrelatingtothescience,technologyandartinthefieldsoflightandlightingandfortheinterchangeofinformationinthesefieldsbetweencountries.

Todevelopbasicstandardsandproceduresofmetrologyinthefieldsoflightandlighting.

Toprovideguidanceintheapplicationofprinciplesandproceduresinthedevelopmentofinternationalandnationalstandardsinthefieldsoflightandlighting.

Toprepareandpublishstandards,reportsandotherpublicationsconcernedwithallmattersrelatingtothescience,technologyandartinthefieldsoflightandlighting.

Tomaintainliaisonandtechnicalinteractionwithotherinternationalorganisationsconcernedwithmattersrelatedtothescience,technology,standardisationandartinthefieldsoflightandlighting.

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TheworkoftheCIEiscarriedonbysevenDivisionseachwithabout20TechnicalCommittees.Thisworkcoverssubjectsrangingfromfundamentalmatterstoalltypesoflightingapplications.ThestandardsandtechnicalreportsdevelopedbytheseinternationalDivisionsoftheCIEareacceptedthroughouttheworld.

AplenarysessionisheldeveryfouryearsatwhichtheworkoftheDivisionsandTechnicalCommitteesisreviewed,reportedandplansaremadeforthefuture.TheCIEisrecognisedastheauthorityonallaspectsoflightandlighting.Assuchitoccupiesanimportantpositionamonginternationalorganisations.

LACOMMISSIONINTERNATIONALEDEL'ECLAIRAGE

LaCommissionInternationaledel'Eclairage(CIE)estuneorganisationquisedonnepourbutlacoopérationinternationaleetl'échanged'informationsentrelesPaysmembressurtouteslesquestionsrelativesàl'artetàlasciencedel'éclairage.ElleestcomposéedeComitésNationauxreprésentant38paysplusunterritoiregéographique,etde4membresassociés.

LesobjectifsdelaCIEsont:

Deconstitueruncentred'étudeinternationalpourtoutematièrerelevantdelascience,delatechnologieetdel'artdelalumièreetdel'éclairageetpourl'échangeentrepaysd'informationsdanscesdomaines.

D'élaborerdesnormesetdesméthodesdebasepourlamétrologiedanslesdomainesdelalumièreetdel'éclairage.

Dedonnerdesdirectivespourl'applicationdesprincipesetdesméthodesd'élaborationdenormesinternationalesetnationalesdanslesdomainesdelalumièreetdel'éclairage.

Deprépareretpublierdesnormes,rapportsetautrestextes,concernanttoutesmatièresrelativesàlascience,latechnologieetl'artdanslesdomainesdelalumièreetdel'éclairage.

Demainteniruneliaisonetunecollaborationtechniqueaveclesautresorganisationsinternationalesconcernéespardessujetsrelatifsàlascience,latechnologie,lanormalisationetl'artdanslesdomainesdelalumièreetdel'éclairage.

LestravauxdelaCIEsonteffectuéspar7Divisions,ayantchacuneenviron20ComitésTechniques.Lessujetsd'étudess'étendentdesquestionsfondamentales,àtouslestypesd'applicationsdel'éclairage.LesnormesetlesrapportstechniquesélaborésparcesDivisionsInternationalesdelaCIEsontreconnusdanslemondeentier.

Touslesquatreans,uneSessionplénièrepasseenrevueletravaildesDivisionsetdesComitésTechniques,enfaitrapportetétablitlesprojetsdetravauxpourl'avenir.LaCIEestreconnuecommelaplushauteautoritéencequiconcernetouslesaspectsdelalumièreetdel'éclairage.Elleoccupecommetelleunepositionimportanteparmilesorganisationsinternationales.

DIEINTERNATIONALEBELEUCHTUNGSKOMMISSION

DieInternationaleBeleuchtungskommission(CIE)isteineOrganisation,diesichderinternationalenZusammenarbeitunddemAustauschvonInformationenzwischenihrenMitgliedsl?ndernbezüglichderKunstundWissenschaftderLichttechnikwidmet.DieMitgliedschaftbestehtausdenNationalenKomiteesin38L?ndernundeinemgeographischenGebietundaus4assoziiertenMitgliedern.

DieZielederCIEsind:

EininternationalerMittelpunktfürDiskussionenallerFragenaufdemGebietderWissenschaft,TechnikundKunstderLichttechnikundfürdenInformationsaustauschaufdiesenGebietenzwischendeneinzelnenL?ndernzusein.

GrundnormenundVerfahrenderMe?technikaufdemGebietderLichttechnikzuentwickeln.

RichtlinienfürdieAnwendungvonPrinzipienundVorg?ngeninderEntwicklunginternationalerundnationalerNormenaufdemGebietderLichttechnikzuerstellen.

Normen,BerichteundanderePublikationenzuerstellenundzuver?ffentlichen,diealleFragenaufdemGebietderWissenschaft,TechnikundKunstderLichttechnikbetreffen.

LiaisonundtechnischeZusammenarbeitmitandereninternationalenOrganisationenzuunterhalten,diemitFragenderWissenschaft,Technik,NormungundKunstaufdemGebietderLichttechnikzutunhaben.

DieArbeitderCIEwirdin7Divisionen,jedemitetwa20TechnischenKomitees,geleistet.DieseArbeitbetrifftGebietemitgrundlegendemInhaltbiszuallenArtenderLichtanwendung.DieNormenundTechnischenBerichte,dievondieseninternationalzusammengesetztenDivisionenausgearbeitetwerden,sindvonderganzenWeltanerkannt.

TagungenwerdenallevierJahreabgehalten,inderdieArbeitenderDivisionenüberprüftundberichtetundneuePl?nefürdieZukunftausgearbeitetwerden.DieCIEwirdalsh?chsteAutorit?tfüralleAspektedesLichtesundderBeleuchtungangesehen.AufdieseWeiseunterh?ltsieeinebedeutendeStellungunterdeninternationalenOrganisationen.

Publishedbythe

CIE2004–Allrightsreserved

COMMISSIONINTERNATIONALEDEL'ECLAIRAGE

CIECentralBureauKegelgasse27,A-1030Vienna,AUSTRIA

Tel:+43(1)71431870,Fax:+43(1)714318718

e-mail:

ciecb@ping.at

WWW:

http://www.cie.co.at/

--`,,,``,-`-`,,`,,`,`,,`

ISBN3901906339

COLORIMETRY

CIE15:2004

3rdEdition

UDC:

535.66

Descriptor:Colorimetry

535.67

Colourofobjects

612.843.31

Colourvision

159.937.51

Perceptionofcolour

CIE15:2004

ThisTechnicalReporthasbeenpreparedbyCIETechnicalCommittee1-48ofDivision1“VisionandColour”andhasbeenapprovedbytheBoardofAdministrationoftheCommissionInternationaledel'Eclairageforstudyandapplication.Thedocumentreportsoncurrentknowledgeandexperiencewithinthespecificfieldoflightandlightingdescribed,andisintendedtobeusedbytheCIEmembershipandotherinterestedparties.Itshouldbenoted,however,thatthestatusofthisdocumentisadvisoryandnotmandatory.ThelatestCIEproceedingsorCIENEWSshouldbeconsultedregardingpossiblesubsequentamendments.

CerapporttechniqueaétéélaboréparleComitéTechniqueCIE1-48delaDivision1“VisionetCouleur”etaétéapprouvéparleBureaudelaCommissionInternationaledel'Eclairage,pourétudeetemploi.Ledocumentexposelesconnaissancesetl'expérienceactuellesdansledomaineparticulierdelalumièreetdel'éclairagedécritici.IlestdestinéàêtreutiliséparlesmembresdelaCIEetpartoutlesintéressés.Ilfautcependantnoterquecedocumentestindicatifetnonobligatoire.IlfautconsulterlesplusrécentscomptesrendusdelaCIE,ouleCIENEWS,encequiconcernedesamendementsnouveauxéventuels.

DieserTechnischeBerichtistvomCIETechnischenKomitee1-48derDivision1“SehenundFarbe”ausgearbeitetundvomVorstandderCommissionInternationaledel'Eclairagegebilligtworden.DasDokumentberichtetüberdenderzeitigenStanddesWissensundErfahrungindembehandeltenGebietvonLichtundBeleuchtung;esistzurVerwendungdurchCIE-MitgliederunddurchandereInteressiertebestimmt.Essolltejedochbeachtetwerden,da?dasDokumenteineEmpfehlungundkeineVorschriftist.DieneuestenCIE-TagungsberichteoderdasCIENEWSsolltenimHinblickaufm?glichesp?tere?nderungenzuRategezogenwerden.

AnymentionoforganisationsorproductsdoesnotimplyendorsementbytheCIE.Whilsteverycarehasbeentakeninthecompilationofanylists,uptothetimeofgoingtopress,thesemaynotbecomprehensive.

Toutementiond'organismeoudeproduitn'impliquepasunepréférencedelaCIE.Malgrélesoinapportéàlacompilationdetouslesdocumentsjusqu'àlamisesouspresse,cetravailnesauraitêtreexhaustif.

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DieErw?hnungvonOrganisationenoderErzeugnissenbedeutetkeineBilligungdurchdieCIE.Obgleichgro?eSorgfaltbeiderErstellungvonVerzeichnissenbiszumZeitpunktderDrucklegungangewendetwurde,istesm?glich,da?diesenichtvollst?ndigsind.

CIE2004–Allrightsreserved

II

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CIE15:2004

ThisreporthasbeenpreparedbytheTechnicalCommittee1-48"RevisionofCIEdocument

15.2Colorimetry"ofCIEDivision1"ColourandVision"byusingpreviouslypublishedmaterialoftheCIEandconsideringresolutionsoftheCIEDivision1meetingatTeddington2000-04-06andRochester2001-06-22/23.ThispresentpublicationreplacesCIE15.2-1986"Colorimetry"I.

MembersoftheTechnicalCommitteeduringthepreparationofthisreportwere:

P.J.Alessi USA

E.C.Carter USA

M.D.Fairchild USA

R.W.G.Hunt UnitedKingdom

C.S.McCamy USA

B.Kránicz Hungary

J.R.Moore UnitedKingdom

L.Morren Belgium

J.H.Nobbs UnitedKingdom

Y.Ohno USA

M.R.Pointer UnitedKingdom

D.C.Rich USA

A.R.Robertson Canada

J.D.Schanda(chair) Hungary

R.Sève France

P.W.Trezona UnitedKingdom

K.Witt Germany

H.Yaguchi Japan

ThefollowingEditorialCommitteewasresponsiblefortheformulationofthedocument:E.C.Carter,Y.Ohno,M.R.Pointer,A.R.Robertson,R.Sève,J.D.Schanda,K.Witt.

ItemsofmainlyhistoricimportancehavebeenplacedintoAppendixA.

IAccordingtothenewCIEpublicationnumberingpolicy-thatindicatesanewrevisededitiononlybytheyearofpublication-thistechnicalreporthasgotthenumberof15:2004andnot15.3:2004.

III

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CIE15:2004

TABLEOFCONTENTS

SUMMARY VII

RESUME VII

ZUSAMMENFASSUNG VII

SCOPE 1

PREFACE 1

RECOMMENDATIONSCONCERNINGSTANDARDPHYSICALDATAOFILLUMINANTSANDSOURCES 2

Recommendationsconcerningstandardphysicaldataofilluminants 2

Artificialsourcesrepresentativeofilluminants 5

RECOMMENDATIONSCONCERNINGSTANDARDOFREFLECTANCE 5

RECOMMENDATIONSCONCERNINGGEOMETRICCONDITIONSFORCOLORIMETRY 5

Recommendednomenclaturefordirectionalirradiation 6

Forty-fivedegreedirectionalgeometry(45°x) 6

Forty-fivedegreeannulargeometry(45°a) 6

Zerodegreedirectionalgeometry(0°) 6

Eightdegreegeometry(8°) 7

Recommendedgeometryforreflectionmeasurements 7

Diffuse:eight-degreegeometry,specularcomponentincluded(di:8°) 7

Diffuse:eight-degreegeometry,specularcomponentexcluded(de:8°) 7

Eightdegree:diffusegeometry,specularcomponentincluded(8°:di) 7

Eightdegree:diffusegeometry,specularcomponentexcluded(8°:de) 7

Diffuse/diffusegeometry(d:d) 7

Alternativediffusegeometry(d:0°) 7

Forty-fivedegreeannular/normalgeometry(45°a:0°) 7

Normal/forty-fivedegreeannulargeometry(0°:45°a) 8

Forty-fivedegreedirectional/normalgeometry(45°x:0°) 8

Normal/forty-fivedegreedirectionalgeometry(0°:45°x) 8

Recommendedgeometryfortransmissionmeasurements 8

Normal/normalgeometry(0°:0°) 8

Diffuse/normalgeometry,regularcomponentincluded(di:0°) 9

Diffuse/normalgeometry,regularcomponentexcluded(de:0°) 9

Normal/diffusegeometry,regularcomponentincluded(0°:di) 9

Normal/diffusegeometry,regularcomponentexcluded(0°:de) 9

Diffuse/diffusegeometry(d:d) 9

RECOMMENDATIONSCONCERNINGSTANDARDOBSERVERDATA 9

CIE1931standardcolorimetricobserver 9

CIE1964standardcolorimetricobserver 10

RECOMMENDATIONSCONCERNINGTHECALCULATIONOFTRISTIMULUSVALUESANDCHROMATICITYCOORDINATES 12

Calculationoftristimulusvalues 12

Secondarylightsources(reflectingortransmittingobjects) 12

Illuminantsandself-luminousobjects 13

Theuseofabridgedortruncateddata 13

Abridgement 13

Truncation 14

Weightingfactors 14

Numericalprocedures 15

Bandwidthofaspectrometer 15

Calculationofchromaticitycoordinates 15

Equationsrepresentingrelationshipsbetweencolourstimuli 16

IV

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CIE15:2004

RECOMMENDATIONSCONCERNINGUNIFORMCOLOURSPACINGAND

COLOURDIFFERENCES 16

CIE1976uniformchromaticityscalediagram(UCSdiagram) 16

CIE1976uniformcolourspaces 16

CIE1976(L*a*b*)colourspace;CIELABcolourspace 17

CIE1976(L*u*v*)colourspace;CIELUVcolourspace 18

NotesonCIE1976uniformcolourspaces 19

Improvedindustrialcolourdifferenceevaluation 20

CIEDE2000totalcolourdifferenceformula 20

RECOMMENDATIONSCONCERNINGMISCELLANEOUSCOLORIMETRICPRACTICESANDFORMULAE 22

Dominantwavelengthandpurity 22

Dominantwavelength(ofacolourstimulus),d 22

Complementarywavelength(ofacolourstimulus),c 22

Colorimetricpurity,pc 22

Excitationpurity,pe 22

Specialmetamerismindices 23

Specialmetamerismindex:changeinilluminant 23

Specialmetamerismindex:changeinobserver 24

Assessmentofthequalityofadaylightsimulatorforcolorimetry 25

Theevaluationofwhiteness 26

Calculationofcorrelatedcolourtemperature 26

REFERENCES 27

TABLES 30

TableT.1.RelativespectralpowerdistributionsofCIEilluminants 30

11.2TableT.2.ComponentsS0(),S1(),S2() 33

TableT.3.Tristimulusvalues,chromaticitycoordinatesofCIEilluminants 35

TableT.4.CIE1931standardcolorimetricobserver 36

TableT.5.CIE1964standardcolorimetricobserver 38

TableT.6.Relativespectralpowerdistributionsofilluminantsrepresentingtypicalfluorescentlamps,forwavelengths=380nmto780nmat5nmintervals 40

TableT.7.Highpressuredischargelamps.HP1:Standardhighpressuresodiumlamp;HP2:Colourenhancedhighpressuresodiumlamp;HP3-5:Threetypesofhighpressuremetalhalidelamps 47

TableT.8.ColorimetricdataforthefluorescentlampilluminantsofTableT.6 49

TableT.9.ColorimetricdataforthehighpressureilluminantsofTableT.7 50

TableT.10.Valuesofthefirstdeviationfunctionusedinthecalculationoftheobservermetamerismindex 51

APPENDIXA.OLDRECOMMENDATIONS,NOWOBSOLETE,ASWELLASREFERENCESTONON-CIECOLOURDIFFERENCEFORMULAE 52

AppendixA.1.IlluminantBandSourceB 52

AppendixA.2.IlluminantCandSourceC 52

AppendixA.3.CIE1964uniformcolourspaceandcolourdifferenceformula 53

u,vuniformchromaticityscale(CIE1960UCS)diagram 53

1964uniformspaceandcolourdifferenceformula 53

AppendixA.4.CIE1994colourdifferenceformula(CIE94) 53

AppendixA.5.CMC(l:c)colourdifferenceformula 54

AppendixA.6.DIN99colourdifferenceformula 54

References 54

APPENDIXB.DEFINITIONSOFTHEr(),g(),b()COLOUR-MATCHINGFUNCTIONS,THECIERGBSYSTEMANDTHEDERIVATIONOFTHECIEXYZ

SYSTEMFROMTHECIERGBSYSTEMFORTHE1931STANDARDOBSERVER 55

AppendixB.1.Determinationofther(),g(),b()colour-matchingfunctions 55

AppendixB.2.DerivationoftheCIEXYZtrichromaticsystemfromtheCIERGBtrichromaticsystem 56

V

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CIE15:2004

AppendixB.3.Definitionofthecolour-matchingfunctionsintheCIE1964trichromaticsystem 57

Reference 61

APPENDIXC.ALTERNATIVEMETHODTODEFINEDAYLIGHTILLUMINANTS-METHODOFCALCULATION,CORRECTEDTABLESANDEQUATIONS(FOR

INFORMATIONANDEVALUATION) 62

References 65

APPENDIXD.REVERSETRANSFORMATIONFROMVALUESL*,a*,b*TO

TRISTIMULUSVALUESX,Y,Z 66

Reference 66

APPENDIXE.INFORMATIONONTHEUSEOFPLANCK’SEQUATIONFOR

STANDARDAIR 67

References 67

EXPLANATORYCOMMENTS 68

VI

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CopyrightInternationalCommissiononIlluminationProvidedbyIHSunderlicensewithCIE

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CIE15:2004

COLORIMETRYSUMMARY

ThispublicationprovidestherecommendationsoftheCIEconcerningbasiccolorimetry.Specifically,itincludestheuseofthestandardilluminantsandthestandardcolorimetricobservers;thereferencestandardforreflectance;theilluminatingandviewingconditions;thecalculationoftristimulusvalues,chromaticitycoordinates,colourspacesandcolourdifferences;andthevariousothercolorimetricpracticesandformulae.

ThispublicationisconsistentwiththefundamentaldataandproceduresdescribedintheCIEStandardsonColorimetry.

Forfurtherdetailsofsomeofthephenomenadiscussedherethereaderisdirectedtotheappropriatetechnicalreports.

COLORIMETRIERESUME

CedocumentdonnelesrecommandationsdelaCIEpourlacolorimétriedebase.Plusparticulièrementiltraitedel'emploidesilluminantsnormalisésetdesobservateurscolorimétriquesnormalisés,delaréférencenormaliséepourlefacteurderéflexion,desconditionsd'éclairageetd'observation,ducalculdescomposantestrichromatiques,descoordonnéestrichromatiques,desespaceschromatiquesetdesécartsdecouleur,ainsiquedel'emploidediversesautrespratiquesetformulescolorimétriques.

CettepublicationestenaccordaveclesdonnéesetprocéduresdebasequisontdécritesdanslesnormesCIEdecolorimétrie.

Pourdesdétailscomplémentairesrelatifsauxquestionstraitéesici,lelecteurestinvitéàconsulterlesrapportstechniquesappropriés.

FARBMESSUNGZUSAMMENFASSUNG

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DiehierwiedergegebenenEmpfehlungenderCIEbeziehensichaufdieAnwendungoderdieBenutzungderNormlichtartenundderNormalbeobachter,aufdenWei?standard,aufdieBeleuchtungs-undBeobachtungsbedingungen,aufdieBerechnungvonNormfarbwertenundNormfarbwertanteilen,Farbenr?umenundFarbabst?nden,undaufverschiedeneanderefarbmetrischePraktikenundFormeln.

DieseVer?ffentlichungstimmtmitdengrundlegendenDatenundVerfahrenüberein,dieinCIENormenfürFarbmessungbeschriebensind.

WeitereEinzelheiteneinigerhierdiskutierterPh?nomenefindetderLeseringeeignetentechnischenBerichten.

VII

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CIE15:2004

VIII

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CIE15:2004

SCOPE

ThisreportisintendedtoprovideaconsistentandcomprehensiveaccountoftherecommendationsoftheCIEforbasiccolorimetry.Itsummarisesbasiccolorimetricdataandpractices;itdoesnot,however,dealwithcolourappearancespecification.

PREFACE

BygeneralconsentinallcountriesthespecificationofbasicstandardsforuseincolorimetryistheprovinceoftheCommissionInternationaledel'Eclairage(CIE).ThefirstmajorrecommendationsregardingcolorimetricstandardsweremadebytheCIEin1931,andtheseformedthebasisofmoderncolorimetry.Theoriginalrecommendationsof1931werereviewedfromtimetotimebytheCIEColorimetryCommitteeandlaterbyCIEDivision1,VisionandColour.Whennecessarychangesweremade.Newrecommendationswereaddedtosupplementtheexistingonesortobroadenthescopeofcolorimetryinaccordancewithdevelopmentsinpracticeandscience.

ThedeliberationsandrecommendationsmadebytheCIEColorimetryCommitteeandDivision1arerecordedintheProceedingsofthevariousSessionsoftheCIE.HowevertheaccesstotheseProceedingshasalwaysbeenratherlimitedandmuchofthematerialpublishedintheProceedingsisobsoleteorinconsistentwithcurrentcolorimetricpractice.Therecommendations,whilefewinnumber,alsopresentanincoherentpicture.Manyrecommendationsaremerelyproposalsofstudyorworkoncertaintopicsthatwereconsideredimportantatthetime.

Forthesereasonsin1971theCIEpublishedaspecialdocumentoncolorimetrytoprovideaconsistentandcomprehensiveaccountofbasiccolorimetricrecommendations.Thisdocumentwasnotintendedtobeatextbookoncolorimetrybutratherareferencetothebasicstandardsthatgovernmoderncolorimetry.ThedocumentwasissuedasCIEPublicationNo.15(CIE,1971).

Since1971ithasbeennecessarytoaddtwosupplementstothedocument[Suppl.1onSpecialmetamerismindex:changeofilluminant(CIE,1972)andSuppl.2onRecommendationsonuniformcolourspaces,colour-differenceequationsandpsychometriccolourterms(CIE,1978)].SeveralTechnicalReportswerealsopublishedduringtheinterveningyears.PublicationCIE15.2,publishedin1986(CIE,1986b)incorporatedthefirsttwosupplements.Furtheramendments,describedindetailinCIE51-1981,Amethodforassessingthequalityofdaylightsimulatorsforcolorimetry(CIE,1981);CIE80-1989,Specialmetamerismindex:observermetamerism(CIE,1989);CIE101-1993,Parametriceffectsincolourdifferenceevaluation(CIE,1993);CIE116-1995,Industrialcolourdifferenceevaluation(CIE,1995a);CIE135/3,CIETC1-45report:Supplement1-1999toCIE51-1981,VirtualmetamersforassessingthequalityofsimulatorsofCIEilluminantD50(CIE,1999b)andCIE142-2001,Improvementtoindustrialcolourdifferenceevaluation(CIE,2001a)areallpartsoftheCIEsystemofcolorimetry.Thepresentversion,CIE15:2004summarisesallCIErecommendationsonbasiccolorimetry.Shortexplanatorytextsandahistoricoverviewarealsoincluded.Colourappearancemodelsarenotcovered,fortheseseeCIE131-1998(CIE,1998a);CIE159:2004(CIE,2004b)andCIEx014-1998(CIE,1998b).

Incompilingthisthirdeditiontheopportunityhasbeentakentoincorporateallrelevantrecommendations.Thepublicationsenumeratedinthepreviousparagraphcontainbackgroundinformationonthesinglesubjects,thoseinterestedinmoredetailaboutthedevelopmentoftherecommendationsandtheirbackgroundexperimentsarereferredtothesepublications.CIE15:2004isbasedonCIEstandardscontainingthefundamentaldataonCIEstandardilluminantsandstandardobservers.ThepresentlyofficialversionsofthesestandardsareCIES005-1998,CIEstandardilluminantsforcolorimetry(CIE,1998c)(publishedalsoasISO10526:1999)andCIES002-1986,CIEstandardcolorimetricobservers(CIE,1986a),(publishedalsoasCIE/ISO10527:1991).Thesestandardscontainthefundamentalcolorimetricdata[seealsoCIEDS014-2.2:2004(CIE,2004a)].

Itisanticipatedthatfurtheramendmentsofcolorimetricpracticeandfurtherstandardswillbepublished,thusoneshouldconsultthelatestCIElistofpublicationspublishedinCIEProceedings,andinmostrecentTechnicalReports;thisinformationisalsoavailableontheCIEworldwidewebhomepage

(http://www.cie.co.at/).

1

CIE15:2004

Thewordingoftheoriginalrecommendationshasbeenalteredtobeconsistentwithmodernnomenclatureandinsomecasestheoriginalrecommendationshavealsobeenmodifiedincontenttobringthemintolinewithpresentdaythinkingandpractice.TheversionsgiveninthisdocumentaretherecommendationsnowinforceandsupersedeallpreviousrecommendationsuntilsuchtimeasanyamendmentsarepublishedbytheCIE.

Therecommendationsaredividedintothefollowingsevengroups:

Recommendationsconcerningstandardphysicaldataofilluminantsandsources.

Recommendationsconcerningthestandardofreflectance.

Recommendationsconcerninggeometricconditionsforcolorimetry.

Recommendationsconcerningstandardobserverdata.

Recommendationsconcerningthecalculationoftristimulusvaluesandchromaticitycoordinates.

Recommendationsconcerninguniformcolourspacingandcolourdifference.

Recommendationsconcerningmiscellaneouscolorimetricpracticesandformulae.

Thedefinitivedatarelatingtostandardcolorimetricilluminantsandobserversarethosegivenat1nmintervalsintheappropriateCIEstandards[CIE,1998c(tobereplacedbyCIE,2004a);CIE,1986a].Thedatahavenotbeenprintedinthepresentreport,butareincludedintheaccompanyingCD-ROM.Abridgeddata,at5nmintervals,aregiveninSection11,andthesemaybeusedinthosecaseswherecalculationatthewiderintervalsisunlikelytoproduceanysignificanterror.

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ForallcolorimetriccalculationswavelengthinstandardairshouldbeusedII1.

RECOMMENDATIONSCONCERNINGSTANDARDPHYSICALDATAOFILLUMINANTSANDSOURCES

Recommendationsconcerningstandardphysicaldataofilluminants2

Itisrecommendedthatthefollowingilluminants,definedbyrelativespectralpowerdistributionsgiveninTable1ofCIES005-1998(CIE,1998c)III,beusedforgeneralcolorimetry.

CIEstandardilluminantA

TherelativespectralpowerdistributionSA()isdefinedbytheequation

1,435107

5

S()100?560?

exp

28485601

(3.1)

?

?

A ??

exp

1,435107

2848 1

whereisthewavelengthinnanometresandthenumericalvaluesinthetwoexponentialtermsaredefinitiveconstantsoriginatingfromthefirstdefinitionofIlluminantAin19313.Thisspectralpowerdistributionisnormalizedtothevalue100(exactly)atthewavelength560nm(exactly).

CIEstandardilluminantAisdefinedoverthespectralregionfrom300nmto830nmIVinCIES005-1998(CIE,1998c)tosixsignificantdigits.Shouldhigherprecisionbeneeded,

IISuperscriptsofArabicnumeralsrefertoExplanatoryCommentsgivenon72.

IIIThespectralpo