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EUROPEAN STANDARD
EN 61966-7-1
NORME EUROPÉENNE
August 2006
EUROPÄISCHE NORM
ICS 33.160.60; 35.180; 37.100.10 Supersedes EN 61966-7-1:2002

English version
Multimedia systems and equipment -
Colour measurement and management
Part 7-1: Colour printers -
Reflective prints -
RGB inputs
(IEC 61966-7-1:2006)
Systèmes et appareils multimédia - Multimediasysteme und -geräte -
Mesure et gestion de la couleur Farbmessung und Farbmanagement
Partie 7-1: Imprimantes couleur - Teil 7-1: Farbdrucker -
Imprimés par réflexion - Reflektierende Drucke -
Entrées RVB RGB-Eingänge
(CEI 61966-7-1:2006) (IEC 61966-7-1:2006)

This European Standard was approved by CENELEC on 2006-07-01. CENELEC 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 Central Secretariat or to any CENELEC member.

This European Standard exists in two official versions (English and German). A version in any other language
made by translation under the responsibility of a CENELEC member into its own language and notified to the
Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61966-7-1:2006 E
Foreword
The text of document 100/1061/FDIS, future edition 2 of IEC 61966-7-1, prepared by IEC TC 100, Audio,
video and multimedia systems and equipment, was submitted to the IEC-CENELEC parallel vote and was
approved by CENELEC as EN 61966-7-1 on 2006-07-01.
This European Standard supersedes EN 61966-7-1:2002.
This European Standard includes the following technical changes with respect to EN 61966-7-1:2002:
a) In addition to the default illuminant, D50, D65, F11 and illuminant A were added as optional
illuminants.
b) The numbering of the colour patches in the test-chart file was changed for easy understanding of the
measurement location.
c) Two test-chart files: short-term instability test chart and spatial non-uniformity test chart were added.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2007-04-01
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2009-07-01
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61966-7-1:2006 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 61966-2-1 NOTE  Harmonized as EN 61966-2-1:2000 (not modified).

__________
- 3 - EN 61966-7-1:2006
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60050-845 1987 International Electrotechnical Vocabulary - -
(IEV) - Chapter 845: Lighting
ISO 216 1975 Writing paper and certain classes of printed EN ISO 216 2001
matter - Trimmed sizes - A and B series

ISO/CIE 10526 1999 CIE standard illuminants for colorimetry - -

ISO/CIE 10527 1991 CIE standard colorimetric observers - -

1)
CIE 15 - Colorimetry - -
1)
Undated reference.
INTERNATIONAL IEC
STANDARD 61966-7-1
Second edition
2006-05
Multimedia systems and equipment –
Colour measurement and management –
Part 7-1:
Colour printers – Reflective prints – RGB inputs

 IEC 2006  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale X
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 61966-7-1  IEC:2006(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .7
4 Letters and symbols .9
5 Conditions .9
5.1 Environmental conditions .9
5.2 Sampling conditions .10
5.3 Measurement conditions.11
5.4 Method of calculation .12
6 Spectral characteristics .14
6.1 Attributes to be measured .14
6.2 Method of measurement .14
6.3 Presentation of the result .14
7 Basic colorimetric characteristics.15
7.1 Attribute to be measured .15
7.2 Method of measurement .15
7.3 Presentation of the results.15
8 Tone reproduction characteristics.16
8.1 Attribute to be measured .16
8.2 Method of measurement .16
8.3 Presentation of the results.17
9 Spatial non-uniformity characteristics .18
9.1 Attribute to be measured .18
9.2 Method of measurement .18
9.3 Presentation of the result .18
10 Temporal instability characteristics.19
10.1 Short-term instability .19
10.2 Long-term instability .20
11 Dependency on illuminant characteristics .23

Annex A (normative) Values in the colour test-chart file .26
Annex B (normative) Specification of the measurement positions in the spatial non-
uniformity test-chart file and the reporting form .32
Annex C (normative) Specification for the measurement of short-term instability
characteristics .37
Annex D (informative) Estimation of effect for backing material change .38
Annex E (informative) Layout of the colour test-chart file reproduced as a reflective print  39
Annex F (informative) Layout of the spatial non-uniformity test-chart file reproduced
as a reflective print .40
Annex G (informative) Layout of the short-term instability test-chart file reproduced as
a reflective print .41

Bibliography.42

– 3 –
61966-7-1  IEC:2006(E)
Figure 1 – Spectral reflectance of the primary and secondary saturated colours, and
white, grey and black .15
* * *
Figure 2 – Example plots for gamut of colours in the CIE 1976 L a b colour space.16
Figure 3 – An example of reporting tone reproduction characteristics.17

Table 1 – Reference to Table A.1 .14
Table 2 – Reference to Table A.3 .17
Table 3 – Conditions for sampling and measurements .19
Table 4 – Specification of data in the colour test chart file and the form for reporting
the result in the long-term instability measurement .22
Table 5 – Specification of colour patches.23
Table 6 – Specification of data in the colour test chart file and the form of reporting the
result of dependency on illuminants measurement – .24
Table 7 – Specification of data in the colour test chart file and the form of reporting the
result of dependency on illuminants measurement – .25
Table A.1 – Specification of the colour test chart file and the form for reporting –
Primary colours.26
Table A.2 – Specification of the colour test-chart file and the form for reporting – 6-by-
6-by-6 cubic data .26
Table A.3 – Specification of the colour test-chart file and the form for reporting – Data
and form for gradation .30
Table B.1 – Form of reporting with measurement positions .32
Table C.1 – Short-term instability characteristics .37

– 4 – 61966-7-1  IEC:2006(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
MULTIMEDIA SYSTEMS AND EQUIPMENT –
COLOUR MEASUREMENT AND MANAGEMENT –

Part 7-1: Colour printers – Reflective prints – RGB inputs

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61966-7-1 has been prepared by Task Area 2: Colour
measurement and management, of IEC technical committee 100: Audio, video and multimedia
systems and equipment.
This second edition cancels and replaces the first edition published in 2001. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition.
a) In addition to the default illuminant, D50, D65, F11 and illuminant A were added as
optional illuminants.
b) The numbering of the colour patches in the test-chart file was changed for easy
understanding of the measurement location.

– 5 –
61966-7-1  IEC:2006(E)
c) Two test-chart files: short-term instability test chart and spatial non-uniformity test chart
were added.
The text of this standard is based on the following documents:
FDIS Report on voting
100/1061FDIS 100/1082/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC 61966 consists of the following parts, under the general title Multimedia systems and
equipment – Colour measurement and management:
Part 1:  General (proposed work item)
Part 2-1: Colour management – Default RGB colour space – sRGB
Part 2-2: Colour management – Extended RGB colour space – scRGB
Part 2-4: Colour management – Extended-gamut YCC colour space for video applications –
xvYC (to be published)
Part 2-5: Colour management – Optional RGB colour space – opRGB (under consideration)
Part 3:  Equipment using cathode ray tubes
Part 4:  Equipment using liquid crystal display panels
Part 5:  Equipment using plasma display panels
Part 6: Front projection displays
Part 7-1: Colour printers – Reflective prints – RGB inputs
Part 7-2: Colour printers – Reflective prints – CMYK inputs (proposed work item)
Part 8:  Multimedia colour scanners
Part 9:  Digital cameras
Part 10: Quality assessment – Colour image in network systems (proposed work item)
Part 11: Quality assessment – Impaired video in network systems (proposed work item)

The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this standard may be issued at a later date.

– 6 – 61966-7-1  IEC:2006(E)
INTRODUCTION
This part of IEC 61966 is applicable to characterization of colour printers that produce colour
on opaque substrate corresponding to digital data files in which colour image information is
expressed in a red–green–blue colour space. The characterization will be realized by
objective measurements to be utilized for colour management in open systems. The
measured and reported results are used to relate the equipment-dependent and undefined red
–green–blue colour space to the default RGB colour space defined as the sRGB by
IEC 61966-2-1. This standard is also applicable to assessment of colour image attributes on
reflective prints reproduced from colour digital image files.
The recommended usage of the standard is for evaluation of the output of home and office
RGB printers.
– 7 –
61966-7-1  IEC:2006(E)
MULTIMEDIA SYSTEMS AND EQUIPMENT –
COLOUR MEASUREMENT AND MANAGEMENT –

Part 7-1: Colour printers – Reflective prints – RGB inputs

1 Scope
This part of IEC 61966 specifies a set of data in colour test chart files for measurements,
sampling of successive prints, measurement conditions and forms of reporting the results so
as to make possible the characterization of the colour printer and comparison of the results of
measurements. The sets of data for measurements are in colour test chart files expressed in
a red–green–blue colour space, to which corresponding colour images are reproduced on
reflective substrate. The methods of measurement in this standard are designed to be
applicable to reflective colour prints for consumer use. The reflective colour prints may be
produced by non-impact colour printers, incorporating such technologies as ink-jet,
sublimation transfer, thermal transfer, electro-photography and other similar technologies.
This standard does not specify limiting values for various attributes.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60050(845):1987, International Electrotechnical Vocabulary (IEV) – Chapter 845: Lighting
ISO 216:1975, Writing paper and certain classes of printed matter – Trimmed sizes – A and B
series
ISO/CIE 10526:1999, CIE standard illuminants for colorimetry
ISO/CIE 10527:1991, CIE standard colorimetric observers
CIE 15, Colorimetry
3 Terms and definitions
For the purposes of this document, terms and definitions which relate to lighting in
IEC 60050(845), as well as the following, apply.
3.1
colour printer
system composed of an application programme to handle colour digital image files, a driver
for equipment that produces colour images on a substrate, and the equipment itself which
accepts equipment specific data for each input channel and is able to process by such
technologies as ink jet, sublimation transfer, thermal transfer, or electro-photography and
other similar technologies
NOTE The colour printer includes a system whereby the equipment that reproduces prints is connected direct to
another piece of equipment in which a set of colour digital image data is contained.

– 8 – 61966-7-1  IEC:2006(E)
3.2
driver
software code which converts output data from an application programme to feed a series of
digital signals to the equipment which produces reflective prints
3.3
application programme
any software which has access to the colour digital image file and output colour image
information to the driver, and possibly renders the colour image on displays
3.4
consumable
any material necessary to run colour printers; for example, sheets of paper, toners, ink, fuser
oil, etc.
3.5
half-tone screen
set of rules for two-dimensional pixel layouts to render a tone
3.6
image
visible two-dimensional representation of electronic signals intended to form a picture
3.7
substrate
opaque substance providing support for a medium
3.8
reflective print
colour image reproduced on a piece of substrate
3.9
gamut of colours
* * *
L a b
three-dimensional maximum range of reproducible colours expressed in the CIE 1976
colour space defined in CIE15
3.10
primary colours
colours used to define a colour space incorporated in the colour digital image file
NOTE Red, green and blue are the primary colours for this standard.
3.11
secondary colours
colours to be defined by a mixture of two primary colours except black
NOTE Cyan, magenta and yellow are the secondary colours for this standard.
3.12
saturated colours
primary colours and secondary colours intended to be reproduced corresponding to their
maximum excitation of electronic signals
NOTE Saturation means the maximum excitation purity (chromaticity) limited by each specific system.
3.13
reproduced colours
colorimetric information measured from the reflective print, expressed in the CIE 1976 colour
space defined in CIE 15
– 9 –
61966-7-1  IEC:2006(E)
3.14
tone reproduction
relationship between data in the colour digital image file which are intended to reproduce the
images of primary, secondary and achromatic colours and the CIE 1976 lightness values of
reflective prints actually reproduced
3.15
characterization
process of obtaining the spectral characteristics, basic colorimetric characteristics, tone
reproduction characteristics, spatial non-uniformity characteristics, temporal instability
characteristics or dependency on illuminant characteristics. In general, these characteristics
relate the input RGB signal to some measured CIE colour values
3.16
electronic signal
data prepared as a colour digital image file intended to form a picture
4 Letters and symbols
The letters and symbols consistently adopted in this part of IEC 61966 are summarized below.
Number of samples of reflective prints for measurements
N
s
*
N
u
Metric in colour difference ΔE for spatial non-uniformity within a page
ab
*
N
t
Metric in colour difference ΔE for short-term instability among successive
ab
reflective prints
p
Printing speed of the colour printer
S(λ) Spectral power distribution of the illuminant D50 as default, D65, F11 and
illuminant A optional
Spectral reflectance of a printed image
ρ(λ)
Digital data in integers fed to colour printers
D , D , D
R G B
N
R , G , B
Data normalized by 2 − 1, where N is the number of bits per channel
~ ~
* Colour in CIE 1976 UCS in reference to printed colour white (see also
~* *
L , a , b
equation (4))
NOTE Special attention should be given to the illuminant and illumination used. Future work is hoped for in this
area for consumer situations.
5 Conditions
5.1 Environmental conditions
Sampling and measurements shall be carried out within the environmental conditions
specified by the manufacturer of the equipment that produces reflective prints, unless
otherwise specified by this standard. The environmental conditions, at least the room
temperature and the relative humidity, during sampling and measurement shall be reported,
together with the presentation of the results of measurements.
NOTE Recommended environmental conditions are a temperature of 20 °C ± 5 °C, a relative humidity of
65 % ± 10 % and atmospheric pressure from 86 kPa to 106 kPa, unless otherwise specified.

– 10 – 61966-7-1  IEC:2006(E)
5.2 Sampling conditions
5.2.1 Substrate
The substrate shall be opaque as specified by the manufacturer of the equipment that
produces reflective prints as either recommended or default. The substrate shall be exposed
for at least one day in order to be accustomed to the environmental conditions.
5.2.2 Settings and operation
5.2.2.1 Half-tone screen
All sampling shall be carried out in the half-tone screen mode whenever applicable. This shall
be as specified by the manufacturer of the equipment that produces reflective prints as either
recommended or default. When multiple options such as half-tone screen for texts, graphics,
and natural pictures are available, the choices shall be reported together with the
presentation of the results of measurements.
If the half-tone screen is not applicable, this shall be reported together with the presentation
of the results.
5.2.2.2 Resolution
All sampling shall be carried out with the resolution setting specified by the manufacturer of
the equipment that produces reflective prints as either recommended or default. When
multiple options such as resolution for texts, graphics, natural pictures are available, the
choices shall be reported together with the presentation of the results of measurements.
5.2.2.3 Miscellaneous settings
Colour rendering, digital filtering and tone reproduction characteristics shall be set as
specified by the manufacturer of the printing equipment that produces reflective prints as
either recommended or default.
The application programme used should provide no extra colour processing or enhancement.
Otherwise, a type of colour processing or enhancement shall be reported.
5.2.3 Number of samples
To minimize an error due to short-term variation and non-uniformity within a page, the number
of samples of reflective prints N should be decided by equation (1), except for Clause 9, and
s
10.1 and 10.2.
2 2
N = N + N (1)
s u t
*
where N is the metric in colour difference ΔE for spatial non-uniformity within a page as
u ab
*
defined in equation (7) and N is the metric in colour difference ΔE for short-term instability
t ab
among successive reflective prints as defined in equation (8).
The number of samples less than N shall be reported together with the presentation of the
s
results of measurements.
NOTE For simplicity of the characterization procedure, N = 1 may be allowed.
s
– 11 –
61966-7-1  IEC:2006(E)
5.2.4 Operation of colour printers
All sampling shall be carried out in line with the conditions specified in the operation manuals
of the colour printer, unless otherwise specified in this standard.
5.2.5 Electric power source
All sampling shall be carried out with an a.c. power source with nominal voltage ±10% of
stable frequency.
5.2.6 Consumables
All sampling shall be carried out with the consumables for the equipment that produces
reflective prints as specified by the manufacturer of the equipment.
5.2.7 Other conditions
All sampling shall be carried out after the warm-up time specified by the manufacturer of the
equipment that produces reflective prints, unless otherwise specified in this standard.
NOTE If the equipment that produces reflective prints has multiple paper trays, any paper tray can be used for
sampling.
5.3 Measurement conditions
5.3.1 General
To minimize an error due to instability of the instruments for colorimetric measurement, the
reflective prints shall be measured at least three times and the measured data shall be
averaged. The number of average times less than three shall be reported together with the
presentation of the results of measurements.
5.3.2 Spectrophotometric and colorimetric measurements
Reflective prints shall be measured successively without any time interval, unless otherwise
specified.
For spectrophotometric measurement, spectral reflectance of the reflective prints shall be
measured over the wavelengths at least from 400 nm to 700 nm every 10 nm for the reflective
print illuminated by incandescent lamps and every 5 nm for the reflective print illuminated by
fluorescent lamps.
NOTE 1 The measurement over the wavelengths from 380 nm to 780 nm is recommended.
NOTE 2 The spectral reflectance should be measured using a spectrophotometer with either 0°/45° or 45°/0°
geometry as specified in ISO 5-4, in order to remove the specular component of the reflected light.
NOTE 3 With some media and colorants, fluorescence may affect the colorimetry measured.
For colorimetric measurement, the spectral radiance of the illumination shall be approximated
to the illuminant D50, as default, defined in Table 1.1 of CIE 15.
The name of the manufacturer of the measuring instrument, the model number and the
manufactured date shall be reported together with the measured results.
5.3.3 Backing material
White backing material, such as five pieces or more of the same substrate on which the colour
image is printed, shall be used. When other backing materials are used, the specification of
the material shall be reported together with the presentation of the results of measurements.
NOTE For estimation of the effect of backing material changes, refer to Annex D.

– 12 – 61966-7-1  IEC:2006(E)
5.4 Method of calculation
5.4.1 Illuminants and colorimetric observers
The illuminant D50, as default, defined in Table 1.1 of CIE 15 and the CIE 1931 Standard
Colorimetric Observer defined in ISO/CIE 10527 shall be used for calculation of the tristimulus
values from the measured spectral data. D65, F11 and illuminant A can be used for the
calculation as optional. If any other illuminants are used, this shall be reported.
NOTE For some measurements, optical reflective density may be used but it should be noted that the measured
values depend on the instruments used for the measurement.
5.4.2 Tristimulus values
The tristimulus values X , Y and Z in the CIE 1931 XYZ colour space for object colours and
illuminant colours shall be calculated by the summations of the products of the spectral power
distribution S(λ) of the illuminant D50 as default, D65, F11 and illuminant A as optional, the
spectral reflectance ρ(λ) of the printed image, and the colour matching functions x(λ) , y(λ) ,
z(λ) , in accordance with equation (2).
X = S(λ)ρ(λ)x(λ)dλ
∫
vis
K
Y = S(λ)ρ(λ)y(λ)dλ (2)
∫
vis
K
Z = S(λ)ρ(λ)z(λ)dλ
∫
vis
K
where K = S()λ y()λ dλ .
∫
vis
5.4.3 CIELAB colour space
* * * * * *
The CIELAB values L , a and b in the CIE 1976 L a b colour space shall be calculated as
in equation (3) in accordance with CIE 15.
 Y  3
*
 
L = 116 − 16
 
Y
 n
1 1
 
  3   3
X Y
*
   
a = 500 − (3)
 
   
X Y
 n  n
 
 
1 1
 
  3   3
Y Z
*
= 200   − 
b
 
   
Y Z
 n  n
 
 
where the tristimulus values X , Y and Z correspond to the default illuminant D50;
n n n
X = 96,42, 0Y = 100,0 and Z = 82,49 to optional illuminant D65; X = 95,04, 0Y = 100,0 and
n n n n n
Z = 108,89 to optional illuminant F11; X = 100,95, 0Y = 100,0 and Z = 64,37 to optional
n n n n
illuminant A; X = 109,85, 0Y = 100,0 and Z = 35,58 .
n n n
Relative values to the colour white shall also be calculated when it is required in accordance
with equation (4).
– 13 –
61966-7-1  IEC:2006(E)
~   3
Y
*
L = 116  − 16
 
Y
 W
1 1
 
    
X 3 Y 3
~*
   
a = 500 − (4)
 
   
X Y
 W  W
 
 
1 1
 
~   3   3
Y Z
*
   
b = 200 −
 
   
Y Z
 W  W 
 
where the tristimulus values X , Y and Z correspond to the printed colour white resulting
W W W
N
from 1D = D =D = 2 − under the illuminant D50 as default, D65, F11 and illuminant A
R G B
optional.
5.4.4 Averaging CIELAB values
The colorimetric values in the CIELAB colour space for reproduced colour chips obtained by
multiple printing jobs shall be averaged over all the measured and calculated values as in
equation (5).
N
s
* *
L = L
n
∑
N
s
n=1
N
s
* *
a = a (5)
∑ n
N
s
n=1
N
s
* *
b = b
∑ n
N
s
n=1
for Clauses 6, 7 and 8, where N is the number of printing jobs defined in equation (1); and
s
M
* *
L = L
m
∑
M
m=1
M
* *
a = a (6)
∑ m
M
m=1
M
* *
b = b
∑ m
M
m=1
* *
for 10.1, where M is the number of printing jobs defined in 10.1.2. For simplicity, L , a and
*
b are written without the bars in the following clauses.

– 14 – 61966-7-1  IEC:2006(E)
6 Spectral characteristics
6.1 Attributes to be measured
Spectral reflectance of reflective prints for primary colours, secondary colours, black and
white.
6.2 Method of measurement
The colour test chart file containing data for red–green–blue as the primary colours, cyan–
magenta–yellow as the secondary colours, and black, grey and white shall be prepared. The
names of the colours and the identification numbers in Table A.1 are shown in Table 1 below.
Table 1 – Reference to Table A.1
Identification Identification
Colour Colour
number number
Red 13B Yellow 15C
Green 14B Black 13A
Blue 15B Grey 14A
Cyan 13C White 15A
Magenta 14C
NOTE Actual data in a red-green-blue colour space in Table A.1 provide examples for the case of 8-bit
quantization for each channel.
All colours shall be reproduced as a piece of reflective print on one sheet of substrate, as
shown in Annex E. Annex E shows alphanumeric characters, such as "01 to 16" vertically and
"A to U" horizontally. The first two digits of the identification number indicate the vertical
position, and the last one digit indicates the horizontal position. It shall be repeated for
N
s
times as specified in equation (1). Spectral reflectance ρ(λ) of each reproduced colour patch
shall be measured by the spectrophotometer in accordance with the specification in 5.3.2.
6.3 Presentation of the result
The spectral reflectance, ρ(λ) , averaged at each wavelength, for the primary saturated
colours, the secondary saturated colours, and black and white shall be plotted as in Figure 1.
The measured spectral reflectance of each colour shall be converted to the CIE 1931 XYZ
* * *
values using equation (2), and the CIELAB values in the CIE 1976 L a b colour space shall
be calculated from the tristimulus values in the CIE 1931 XYZ colour space in accordance with
equation (3). The CIELAB values shall be averaged as in equation (5) and entered in the form
shown in Table A.1 at the column positions specified in Table 1.

– 15 –
61966-7-1  IEC:2006(E)
1 1
9 6
0,8 0,8
1 5
0,6 0,6
0,4 0,4
0,2 0,2
0 0
400 450 500 550 600 650 700
400 450 500 550 600 650 700
Wavelength  nm
Wavelength  nm
IEC  832/01 IEC  833/01
Figure 1a – Spectral reflectance of the primary Figure 1b – Spectral reflectance of the secondary
saturated colours, grey and white saturated colours and black

NOTE Identification numbers of the plots are the same as in Table 1.
Figure 1 – Spectral reflectance of the primary and secondary saturated colours,
and white, grey and black
7 Basic colorimetric characteristics
7.1 Attribute to be measured
Relationship between the data in red–green–blue in the colour test chart file and reproduced
corresponding colours as reflective prints.
7.2 Method of measurement
The colour test chart file containing data for the 6-by-6-by-6 cubic data points specified by the
data identification numbers in Table A.2 shall be used. The file shall be processed to obtain a
piece of reflective print on one sheet of substrate as an arrangement of colour patches, as
shown in Annex E, for N times, as specified in equation (1).
s
NOTE The number of the cubic data points may be increased, for example, to account for discontinuities or non-
monotonic artefacts indicated in Figure 3.
The spectral reflectance of each colour patch of the reflective print should be measured. The
measured data shall be calculated according to equation (2). The tristimulus values and
X , Y
* * *
Z shall be converted to the CIELAB colour space, L , a and b in accordance with equation
(3), which shall be averaged as in equation (5).
NOTE For simplicity of the measurement procedure, colorimeters may be used to acquire the tristimulus values
X, Y and Z directly in accordance with the specification in 5.3.2.
7.3 Presentation of the results
Results of the measurement followed by the calculation shall be entered in the corresponding
column positions of Table A.2. The reported CIELAB values shall also be plotted as in Figure
2.
Reflectance
Reflectance
– 16 – 61966-7-1  IEC:2006(E)
–50
–100
–100 –50 0 50 100
a*
IEC  834/01
* *
Figure 2a – Gamut of colours in b versus a plane
L* L*
100 100
80 80
60 60
40 40
20 20
0 0
–100 –50 0 50 100
–100 –50 0 50 100
a*
b*
IEC  835/01 IEC  836/01
* * * *
Figure 2b – Gamut of colours in L versus a plane Figure 2c – Gamut of colours in L versus b plane

* * *
Figure 2 – Example plots for gamut of colours in the CIE 1976 L a b colour space
8 Tone reproduction characteristics
8.1 Attribute to be measured
Relationship between the input data for the primary and secondary colours and black, and the
CIE 1976 lightness of the reproduced colours.
8.2 Method of measurement
The colour test-chart file containing data specified by Table 2 for the input full-scale ranges
shall be prepared for the primary colours, the secondary colours, and black. Table 2 shows
the identification numbers corresponding to Table A.3 for each set of colours for reproduction
and measurements.
b*
– 17 –
61966-7-1  IEC:2006(E)
Table 2 – Reference to Table A.3
Colour Identification numbers Colour Identification numbers
Red From 01S to 15S Magenta From 14D to 14R
Green From 01T to 15T Yellow From 15D to 15R
Blue From 01U to 15U Black From 16A to 16U
Cyan From 13D to 13R
The file shall be processed to obtain a piece of reflective print on one sheet of substrate as an
arrangement of colour patches, as shown in Annex E, for N times, as specified in equation
s
(1).
NOTE The number of cubic data points may be increased, for example, to account for discontinuities or non-
monotonic artefacts indicated in Figure 3.
The spectral reflectance of each colour patch of the reflective print shall be measured and the
measured data shall be calculated according to equation (2). One of the tristimulus values, Y ,
*
shall be converted to the lightness L in the CIELAB colour space in accordance with
*
equation (3). The lightness L shall be averaged as in equation (5).
NOTE For simplicity of the measurement procedure, colorimeters may be used to acquire one of the tristimulus
values Y directly in accordance with the specification in 5.3.2.
8.3 Presentation of the results
The measured and calculated results, including the rest of the CIELAB values shall be
*
reported in the columns specified in Table 2 to Table A.1. The averaged lightness L versus
normalized input data shall also be reported as the plots shown in Figure 3, where normalized
input data for red and cyan is (2R + G + B) 4 , for green and magenta is (R + 2G + B) 4 and for
black is (R + G + B) 3 .
100 100
90 90
80 80
yellow
70 70
green
cyan
black
60 60
black
magenta
50 50
red
40 40
30 blue 30
20 20
10 10
0 0
0 0,2 0,4 0,6 0,8 1,0 0 0,2 0,4 0,6 0,8 1,0
Normalized input Normalized input

IEC  837/01 IEC  838/01
Figure 3a – Tone reproduction for red, green, Figure 3b – Tone reproduction for cyan, magenta,
blue and black yellow and black

NOTE Output characteristics such as lightness versus chroma may be reported to show gradations.
Figure 3 – An example of reporting tone reproduction characteristics

CIE 1976 lightness
CIE 1976 lightness
– 18 – 61966-7-1  IEC:2006(E)
9 Spatial non-uniformity characteristics
9.1 Attribute to be measured
Non-uniformity of achromatic image reproduced within one sheet of substrate.
9.2 Method of measurement
The data in the spatial non-uniformity test chart file for this measurement shall be 80 % of the
full scale for red–green–blue.
The size of the substrate shall be either A4 defined by ISO 216 or letter size . If another size
is recommended by the manufacturer of the equipment that reproduces the reflective print, it
shall be reported together with the presentation of the results of measurements.
The location of the measurement points should be defined from top-left of the substrate in
landscape and 15 mm ± 2 mm distance to the bottom-right repeatedly, until the next data
point is outside of the substrate. An example of the points is shown in Table B.1. If the
location of data points is different from the recommendation, it shall be reported together with
the presentat
...