EN ISO 18314-4:2024
(Main)Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of illuminant (ISO 18314-4:2024)
Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of illuminant (ISO 18314-4:2024)
This document specifies a formalism for the calculation of the illuminant metamerism of solid surface colours. It cannot be applied to colours of effect coatings without metrical adaptation.
This document only covers the phenomenon of metamerism for change of illuminant, which has the greatest meaning in practical application. In the case where chromaticity coordinates of a pair of samples under reference conditions do not exactly match, this document gives guidance on which correction measures to take. Regarding the reproduction of colours, the metamerism index is used as a measure of quality in order to specify tolerances for colour differences between a colour sample and a colour match under different illumination conditions.
The quantification of the illuminant metamerism of pairs of samples is formally performed by a colour difference assessment, for which tolerances that are common for the evaluation of residual colour differences can be used.
NOTE In the colorimetric literature and textbooks, the term geometric metamerism is sometimes used for the case where two colours appear to be the same under a specific geometry for visual assessment and selected standard observer and standard illuminant pair, but are perceived as two different colours at changed observation geometry. The term geometric metamerism is different to metamerism described in this document.
Analytische Farbmessung - Teil 4: Metamerie-Index von Probenpaaren bei Lichtartwechsel (ISO 18314-4:2024)
Dieses Dokument legt einen Formalismus zur Berechnung der Lichtart-Metamerie von Uni-Farben fest. Dieser kann ohne Anpassungen in der Metrik nicht auf Effektfarben von Überzügen bzw. Beschichtungen angewendet werden.
Dieses Dokument behandelt nur das Phänomen der Metamerie bei Lichtartwechsel, das in der praktischen Anwendung die größte Bedeutung hat. Für die Fälle, in denen die Farborte eines Probenpaares unter Referenz¬bedingungen nicht exakt übereinstimmen, enthält dieses Dokument Leitlinien für die zu ergreifenden Korrekturmaßnahmen. Bei der Reproduktion von Farben wird der Metamerie-Index als Qualitätsmaß verwendet, um Toleranzen für Farbabstände zwischen einer Farbvorlage und einer Farbnachstellung bei unterschiedlichen Beleuchtungsbedingungen festzulegen.
Die Quantifizierung der Lichtart-Metamerie von Probenpaaren wird formal auf eine Farbabstandsbewertung zurückgeführt, bei der Toleranzen herangezogen werden können, die bei der Bewertung reiner Restfarb¬abstände üblich sind.
ANMERKUNG In der Farbliteratur und Fachbüchern wird manchmal auch der Begriff der geometrischen Metamerie für den Fall verwendet, in dem zwei Farben unter einer bestimmten Beobachtungsgeometrie und einer gewählten Kombination aus Normalbeobachter und Lichtart gleich erscheinen, aber bei veränderter Beobachtungsgeometrie als zwei verschiedene Farben wahrgenommen werden. Der Begriff geometrische Metamerie unterscheidet sich von der in diesem Dokument beschriebenen Metamerie.
Analyse colorimétrique - Partie 4: Indice de métamérisme de paires d'échantillons pour changement d'illuminant (ISO 18314-4:2024)
Le présent document spécifie un formalisme pour le calcul du métamérisme de l’illuminant de couleurs de surfaces solides. Il ne s’applique pas à des couleurs de revêtements à effets sans adaptation métrique.
Le présent document ne couvre que le phénomène de métamérisme pour changement d’illuminant, qui a la plus grande signification dans l’application pratique. Dans le cas où les coordonnées trichromatiques d’une paire d’échantillons dans des conditions de référence ne correspondent pas exactement, le présent document fournit des recommandations sur les mesures de correction à prendre. En ce qui concerne la reproduction de couleurs, l’indice de métamérisme est utilisé comme mesure de qualité, de manière à spécifier des tolérances pour les écarts de couleurs entre un échantillon de couleurs et un appariement des couleurs dans différentes conditions d’éclairage.
La quantification du métamérisme de l’illuminant de paires d’échantillons est formellement réalisée par une évaluation de l’écart de couleur, pour laquelle des tolérances communes à l’évaluation d’écarts de couleurs résiduels peuvent être utilisées.
NOTE Dans la littérature et les manuels relatifs à la colorimétrie, le terme métamérisme géométrique est parfois utilisé dans le cas où deux couleurs semblent être identiques sous une géométrie spécifique pour l’évaluation visuelle et l’observateur de référence sélectionné et la paire d’illuminants normalisés, mais sont perçues comme deux couleurs différentes lorsque la géométrie d’observation est changée. Le terme métamérisme géométrique est différent du métamérisme décrit dans le présent document.
Analizna kolorimetrija - 4. del: Metamerični indeks parov vzorcev pri spremembi vrste svetila (ISO 18314-4:2024)
Ta dokument določa formalni postopek za izračun metamerizma barv na
trdni površini pri različnih svetilih. Postopka ni mogoče uporabiti za prevleke s posebnim barvnim učinkom brez metrične prilagoditve.
Ta dokument zajema samo pojav metamerizma pri spremembi svetila v najširšem pomenu praktične uporabe. Kjer se kromatske koordinate para vzorcev pod referenčnimi pogoji povsem ne ujemajo, ta dokument podaja napotke o potrebnih korektivnih ukrepih. Metamerični indeks se v zvezi z reprodukcijo barv uporablja kot meritev kakovosti za določanje odstopanja barvnih razlik med barvnim vzorcem in barvnim ujemanjem v različnih pogojih osvetlitve.
Kvantifikacija metamerizma parov vzorcev različnih svetil se formalno izvede z oceno barvne
različnosti, za katero se lahko uporabijo dovoljena odstopanja, ki so običajna pri ocenjevanju razlik ostankov barv.
OPOMBA: V literaturi in učbenikih o kolorimetriji se izraz geometrični metamerizem včasih uporablja za primere, kjer se dve barvi zdita enaki v določeni geometriji za vizualno oceno in pri izbranem standardnem opazovalcu in standardnem paru svetil, vendar se pri spremenjeni geometriji opazovanja dojemata kot dve različni barvi.
Izraz geometrični metamerizem se razlikuje od metamerizma, ki je opisan v tem dokumentu.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-marec-2024
Nadomešča:
SIST EN ISO 18314-4:2021
Analizna kolorimetrija - 4. del: Metamerični indeks parov vzorcev pri spremembi
vrste svetila (ISO 18314-4:2024)
Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of
illuminant (ISO 18314-4:2024)
Analytische Farbmessung - Teil 4: Metamerie-Index von Probenpaaren bei
Lichtartwechsel (ISO 18314-4:2024)
Analyse colorimétrique - Partie 4: Indice de métamérisme de paires d'échantillons pour
changement d'illuminant (ISO 18314-4:2024)
Ta slovenski standard je istoveten z: EN ISO 18314-4:2024
ICS:
17.180.20 Barve in merjenje svetlobe Colours and measurement of
light
87.060.10 Pigmenti in polnila Pigments and extenders
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 18314-4
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2024
EUROPÄISCHE NORM
ICS 87.060.10 Supersedes EN ISO 18314-4:2021
English Version
Analytical colorimetry - Part 4: Metamerism index for
pairs of samples for change of illuminant (ISO 18314-
4:2024)
Analyse colorimétrique - Partie 4: Indice de Analytische Farbmessung - Teil 4: Metamerie-Index
métamérisme de paires d'échantillons pour von Probenpaaren bei Lichtartwechsel (ISO 18314-
changement d'illuminant (ISO 18314-4:2024) 4:2024)
This European Standard was approved by CEN on 20 October 2023.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18314-4:2024 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 18314-4:2024) has been prepared by Technical Committee ISO/TC 256
"Pigments, dyestuffs and extenders" in collaboration with Technical Committee CEN/TC 298 “Pigments
and extenders” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by July 2024, and conflicting national standards shall be
withdrawn at the latest by July 2024.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 18314-4:2021.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 18314-4:2024 has been approved by CEN as EN ISO 18314-4:2024 without any
modification.
International
Standard
ISO 18314-4
Second edition
Analytical colorimetry —
2024-01
Part 4:
Metamerism index for pairs of
samples for change of illuminant
Analyse colorimétrique —
Partie 4: Indice de métamérisme de paires d'échantillons pour
changement d'illuminant
Reference number
ISO 18314-4:2024(en) © ISO 2024
ISO 18314-4:2024(en)
© ISO 2024
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ii
ISO 18314-4:2024(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 Reference illuminant . 3
6 Test illuminant . 3
7 CIELAB coordinates L*, a*, b* . 3
8 Metamerism index for change in illuminant . 4
8.1 General calculation methods .4
8.2 Basic calculation of the metamerism index from colour differences .5
8.3 Correction methods .5
8.3.1 Additive correction .5
8.3.2 Multiplicative correction .5
8.3.3 Spectral correction.6
8.4 Test report .10
Annex A (informative) Calculation examples .11
Bibliography .24
iii
ISO 18314-4:2024(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
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this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 256, Pigments, dyestuff and extenders, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 298,
Pigments and extenders, in accordance with the Agreement on technical cooperation between ISO and CEN
(Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 18314-4:2020), which has been technically
revised.
The main changes are as follows:
— a brief introduction about differentiation between metamerism and paramerism has been added in 8.1;
— Formula (1) has been updated to align with Formulae (2) and (4) to (24);
— the key of Figure A.1 has been updated.
A list of all parts in the ISO 18314 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
ISO 18314-4:2024(en)
Introduction
This document distinguishes three kinds of metamerism of pairs of samples:
a) Illuminant metamerism occurs if both of the object colours of a pair of samples are perceived as being
the same only under a specific illuminant (e.g. under illuminant D65), while they differ under a different
illuminant (e.g. illuminant A).
b) Observer metamerism occurs if the object colours of a pair of samples are perceived as being the same
by one observer, while a different observer perceives a colour difference under the same illuminant and
the same reference conditions.
NOTE 1 The observer metamerism is caused by differences between the distributions of spectral colour
matching functions of different observers.
c) Field-size metamerism occurs if both of the object colours of a pair of samples are perceived as being the
same on the retina for a size of an observation field (e.g. determined by the 2° standard observer), while
they differ for a different observation field on the retina (e.g. 10°).
NOTE 2 The reason for field-size metamerism is based on the existent colour matching functions of an obs
...
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