Designation:E2729−09(Reapproved2015)StandardPracticeforRectificationofSpectrophotometricBandpassDifferences1ThisstandardisissuedunderthefixeddesignationE2729;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisstandardoutlinesthemethodsthatcanbeusedtodeconvolve,atleastpartially,thespectralbandpassdifferencesofrawspectraldataacquiredbyabridgedspectrophotometry.Suchdifferencesareintroducedbecausethespectralpassbandmustbeofsignificantbandwidthtoallowsufficientenergytoreachthedetector.Ontheotherhand,thespectraldatathatshouldbebeingreportedisthatofavirtual1-nmbandwidthspectruminordertobeusefulintheCIEmethodoftristimulusintegrationwhichinvolves1-nmsummation.1.2Thestandardestablishespracticesforwhether,when,andhowabandpassrectificationshouldbemadetoanyreflectanceortransmittancespectrumacquiredbyabridgedspectrophotometry.1.3Itisapplicablewheretheshapeofthepassbandistriangularandthebandwidthisequaltothemeasurementintervalbetweenpassbands.InformationisprovidedinSection7foruserswhenthatconditionisnotsatisfactorilymet.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2E284TerminologyofAppearanceE308PracticeforComputingtheColorsofObjectsbyUsingtheCIESystem3.Terminology3.1Definitions—Fordefinitionoftermsusedinthispractice,refertoTerminologyE284.3.2DefinitionsofTermsSpecifictoThisStandard:3.2.1virtual1-nmbandwidthspectrum,n—spectraldatathathavebeencorrectedbynumericalmethodssoastomatchascloselyaspossibleaspectrumfromthesamesourcebutwithaputativebandwidthof1nm.4.SummaryofPractice4.1Thepracticeassumesthattheshapeofthepassbandistriangula...
