EN ISO 18314-4:2021
(Main)Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of illuminant (ISO 18314-4:2020)
Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of illuminant (ISO 18314-4:2020)
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 of chromaticity coordinates of a pair of samples under reference conditions that do not exactly match, recommendations are given on which correction measures are to be taken. 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 that two colours appear to be the same under a specific geometry for visual assessment and selected standard observer and standard illuminant pair, but is 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 18314-4:2020)
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 den Fall, dass die Farborte eines Probenpaares unter Referenzbedingungen nicht exakt übereinstimmen, werden Empfehlungen gegeben, welche Korrekturmaßnahmen zu ergreifen sind. Bei der Reproduktion von Farben wird der Metamerie-Index als Qualitätsmaß verwendet, um Toleranzen für Farbunterschiede 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 Restfarbabstände üblich sind.
ANMERKUNG In der Farbliteratur und Fachbüchern wird manchmal auch der Begriff der Geometrischen Metamerie für den Fall verwendet, dass 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 metamérisme de paires d'échantillon pour changement d'illuminant (ISO 18314-4:2020)
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 de coordonnées de chromaticité d’une paire d’échantillons dans des conditions de référence qui ne correspondent pas exactement, des recommandations sont données 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 couleurs, pour laquelle des tolérances communes à l'évaluation d’écarts résiduels de couleurs 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 18314-4:2020)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-september-2021
Analizna kolorimetrija - 4. del: Metamerični indeks parov vzorcev pri spremembi
vrste svetila (ISO 18314-4:2020)
Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of
illuminant (ISO 18314-4:2020)
Analytische Farbmessung - Teil 4: Metamerie-Index von Probenpaaren bei
Lichtartwechsel (ISO 18314-4:2020)
Analyse colorimétrique - Partie 4: Indice de metamérisme de paires d'échantillon pour
changement d'illuminant (ISO 18314-4:2020)
Ta slovenski standard je istoveten z: EN ISO 18314-4:2021
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
June 2021
EUROPÄISCHE NORM
ICS 87.060.10
English Version
Analytical colorimetry - Part 4: Metamerism index for
pairs of samples for change of illuminant (ISO 18314-
4:2020)
Analyse colorimétrique - Partie 4: Indice de Analytische Farbmessung - Teil 4: Metamerie-Index
metamérisme de paires d'échantillon pour changement von Probenpaaren bei Lichtartwechsel (ISO 18314-
d'illuminant (ISO 18314-4:2020) 4:2020)
This European Standard was approved by CEN on 21 June 2021.
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, Turkey 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18314-4:2021 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
The text of ISO 18314-4:2020 has been prepared by Technical Committee ISO/TC 256 "Pigments,
dyestuffs and extenders” of the International Organization for Standardization (ISO) and has been taken
over as EN ISO 18314-4:2021 by 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 December 2021, and conflicting national standards
shall be withdrawn at the latest by December 2021.
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.
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, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 18314-4:2020 has been approved by CEN as EN ISO 18314-4:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 18314-4
First edition
2020-08
Analytical colorimetry —
Part 4:
Metamerism index for pairs of
samples for change of illuminant
Analyse colorimétrique —
Partie 4: Indice de metamérisme de paires d'échantillon pour
changement d'illuminant
Reference number
ISO 18314-4:2020(E)
©
ISO 2020
ISO 18314-4:2020(E)
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
ISO 18314-4:2020(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 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 . 4
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 . 9
Annex A (informative) Calculation examples .10
Bibliography .23
ISO 18314-4:2020(E)
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
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.
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 2020 – All rights reserved
ISO 18314-4:2020(E)
Introduction
For the phenomenon of metamerism of pairs of samples, three different kinds are distinguished:
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. defined 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 observer during an observation situation. The colour matching functions change with the size of the
observation field on the retina. Such change of the observation field can also occur if, for example, the pair of
samples is examined from different distances.
INTERNATIONAL STANDARD ISO 18314-4:2020(E)
Analytical colorimetry —
Part 4:
Metamerism index for pairs of samples for change of
illuminant
1 Scope
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 of chromaticity coordinates of a pair of samples
under reference conditions that do not exactly match, recommendations are given on which correction
measures are to be taken. 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
...
SLOVENSKI STANDARD
01-september-2021
Analizna kolorometrija - 4. del: Metamerični indeks parov vzorcev pri spremembi
vrste svetila (ISO 18314-4:2020)
Analytical colorimetry - Part 4: Metamerism index for pairs of samples for change of
illuminant (ISO 18314-4:2020)
Analytische Farbmessung - Teil 4: Metamerie-Index von Probenpaaren bei
Lichtartwechsel (ISO 18314-4:2020)
Analyse colorimétrique - Partie 4: Indice de metamérisme de paires d'échantillon pour
changement d'illuminant (ISO 18314-4:2020)
Ta slovenski standard je istoveten z: EN ISO 18314-4:2021
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
June 2021
EUROPÄISCHE NORM
ICS 87.060.10
English Version
Analytical colorimetry - Part 4: Metamerism index for
pairs of samples for change of illuminant (ISO 18314-
4:2020)
Analyse colorimétrique - Partie 4: Indice de Analytische Farbmessung - Teil 4: Metamerie-Index
metamérisme de paires d'échantillon pour changement von Probenpaaren bei Lichtartwechsel (ISO 18314-
d'illuminant (ISO 18314-4:2020) 4:2020)
This European Standard was approved by CEN on 21 June 2021.
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, Turkey 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18314-4:2021 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
The text of ISO 18314-4:2020 has been prepared by Technical Committee ISO/TC 256 "Pigments,
dyestuffs and extenders” of the International Organization for Standardization (ISO) and has been taken
over as EN ISO 18314-4:2021 by 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 December 2021, and conflicting national standards
shall be withdrawn at the latest by December 2021.
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.
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, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 18314-4:2020 has been approved by CEN as EN ISO 18314-4:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 18314-4
First edition
2020-08
Analytical colorimetry —
Part 4:
Metamerism index for pairs of
samples for change of illuminant
Analyse colorimétrique —
Partie 4: Indice de metamérisme de paires d'échantillon pour
changement d'illuminant
Reference number
ISO 18314-4:2020(E)
©
ISO 2020
ISO 18314-4:2020(E)
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
ISO 18314-4:2020(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 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 . 4
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 . 9
Annex A (informative) Calculation examples .10
Bibliography .23
ISO 18314-4:2020(E)
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
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.
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 2020 – All rights reserved
ISO 18314-4:2020(E)
Introduction
For the phenomenon of metamerism of pairs of samples, three different kinds are distinguished:
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. defined 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 observer during an observation situation. The colour matching functions change with the size of the
observation field on the retina. Such change of the observation field can also occur if, for example, the pair of
samples is examined from different distances.
INTERNATIONAL STANDARD ISO 18314-4:2020(E)
Analytical colorimetry —
Part 4:
Metamerism index for pairs of samples for change of
illuminant
1 Scope
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 of chromaticity coordinates of a pair of samples
under reference conditions that do not exactly match, recommendations are given on which correction
measures are to be taken. 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
...
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