ISO 12647-8:2021
(Main)Graphic technology — Process control for the production of half-tone colour separations, proof and production prints — Part 8: Validation print processes working directly from digital data
Graphic technology — Process control for the production of half-tone colour separations, proof and production prints — Part 8: Validation print processes working directly from digital data
This document specifies requirements that can be used for determining the conformance of systems that produce a hard-copy validation print, directly from digital data, which is intended to simulate the expected appearance of material printed in accordance with a characterized printing condition. It is not intended for use in determining the conformance of production printing systems (digital or conventional) since many aspects of production printing are not covered in this document.
Technologie graphique — Contrôle des processus de confection de sélections couleurs tramées, d'épreuves et de tirages — Partie 8: Processus d'impression de maquette couleur produite à partir de données numériques
Grafična tehnologija - Vodenje procesa izdelave rastriranih barvnih izvlečkov, preskusnih in proizvodnih odtisov - 8. del: Vrednotenje postopka tiskanja, izdelanega neposredno iz digitalnih podatkov
Ta dokument določa zahteve, ki jih je mogoče uporabiti pri določanju skladnosti sistemov, ki izdelajo papirno različico tiska neposredno iz digitalnih podatkov, ki je namenjena simuliranju pričakovane oblike gradiva, natisnjenega v skladu z opisanimi pogoji tiskanja.
Ni namenjen določanju skladnosti sistemov proizvodnega tiskanja (digitalnih ali običajnih), saj ta dokument ne zajema številnih vidikov proizvodnega tiskanja.
General Information
Relations
Buy Standard
Standards Content (Sample)
SLOVENSKI STANDARD
SIST ISO 12647-8:2022
01-maj-2022
Nadomešča:
SIST ISO 12647-8:2014
Grafična tehnologija - Vodenje procesa izdelave rastriranih barvnih izvlečkov,
preskusnih in proizvodnih odtisov - 8. del: Vrednotenje postopka tiskanja,
izdelanega neposredno iz digitalnih podatkov
Graphic technology - Process control for the production of half-tone colour separations,
proof and production prints - Part 8: Validation print processes working directly from
digital data
Technologie graphique - Contrôle des processus de confection de sélections couleurs
tramées, d'épreuves et de tirages - Partie 8: Processus d'impression de maquette
couleur produite à partir de données numériques
Ta slovenski standard je istoveten z: ISO 12647-8:2021
ICS:
37.100.01 Grafična tehnologija na Graphic technology in
splošno general
SIST ISO 12647-8:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST ISO 12647-8:2022
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SIST ISO 12647-8:2022
INTERNATIONAL ISO
STANDARD 12647-8
Second edition
2021-05
Graphic technology — Process control
for the production of half-tone colour
separations, proof and production
prints —
Part 8:
Validation print processes working
directly from digital data
Technologie graphique — Contrôle des processus de confection de
sélections couleurs tramées, d'épreuves et de tirages —
Partie 8: Processus d'impression de maquette couleur produite à
partir de données numériques
Reference number
ISO 12647-8:2021(E)
©
ISO 2021
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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 2021 – All rights reserved
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Requirements . 3
4.1 Data requirements for validation print systems . 3
4.2 Validation print . 3
4.2.1 Validation print substrate qualification . 3
4.2.2 Coloration of printed parts . 3
4.2.3 Short- and long-term repeatability . 4
4.2.4 Permanence . . 5
4.2.5 Ink set gloss . 6
4.2.6 Tone value reproduction limits . 6
4.2.7 Tonality assessment . 6
4.2.8 Reproduction of vignettes . 6
4.2.9 Image resolving power . 7
4.2.10 Margin information . 7
5 Test methods . 8
5.1 System validation . 8
5.2 Validation print control strip . 8
5.3 Additional test objects . 8
5.4 Uniformity measurement . 9
5.5 Colour measurement . 9
5.6 Measurement of gloss . 9
5.7 Supplementary visual control element . 9
Annex A (normative) Technical requirements for validation print conformity .10
Annex B (informative) Determination of print durability after stabilization .12
Annex C (normative) Surface gamut patches .15
Annex D (informative) Categorising fluorescence .21
Bibliography .22
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SIST ISO 12647-8:2022
ISO 12647-8:2021(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 130, Graphic technology.
This second edition cancels and replaces the first edition (ISO 12647-8:2012), which has been
technically revised.
The main changes compared to the previous edition are as follows:
*
— CIE 1976 ∆E has been replaced with modern ∆E colour difference formulae;
ab 00
— a better metric for uniformity assessment, namely the measurement of 1D distortions of macroscopic
uniformity utilizing scanning spectrophotometers, has been added;
— a more content oriented control wedge has been added;
— a new Annex A has been added to align the content with ISO 12647-7, with respect to substrate
categorisation and conformance assessment;
— informative metrics that proved to be not practical, such as tonality, have been deleted.
A list of all parts in the ISO 12647 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 2021 – All rights reserved
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
Introduction
This document specifies the properties, and associated test methods, required for digital prints and
printing processes to meet the criteria established for “validation prints”.
In most printing workflows, there is a requirement for a visual representation of the expected
appearance of the document being printed that can be used as part of the agreement between customer
and printer. Where this visual representation is produced such that its characteristics (colour fidelity,
tone reproduction, registration, size, etc.) simulate those of the expected printing within tight
tolerances, it is usually referred to as a “contract proof”. As the name implies, contract proofs are used as
part of the contractual relationship between customer and printer and are used as a visual aim for the
press operator during printing as well as the absolute reference against which the finished production
is compared. Not unexpectedly, systems that can produce contract proofs are usually expensive and
require careful operation and maintenance. ISO 12647-7 specifies the requirements for contract proofs
and systems used to produce contract proofs directly from digital data.
Recently, other visualizations of the final printed product have found a place in the printing/proofing
workflow because designers and print buyers prefer not to go to the expense of using an ISO 12647-7
compliant contract proof any earlier in the process than necessary. In many situations, participants in
the workflow require a hardcopy visual reference of lesser quality than a contract proof. In the past,
those prints varied widely in quality and were often referred to as design proofs, concept proofs, layout
prints, etc. That quality level is here being referred to as a “validation print”.
Because data are exchanged electronically, and visualizations of those data are produced at multiple
sites, there is a requirement for defined requirements for validation prints to allow a degree of
consistency throughout the workflow. One of the goals of having less stringent requirements,
particularly on colour fidelity, is to allow the production of validation prints on less elaborate and less
costly devices than are required for contract proofs. The requirements for validation prints and the
systems used to produce validation prints are given in this document.
Validation prints are not intended to replace “contract proofs” for predicting colour on production
printing devices. It is expected that the modifications of the requirements for validation prints, along
with the requirements for contract proofs, will continue in the future as industry requirements and
imaging technologies develop.
© ISO 2021 – All rights reserved v
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SIST ISO 12647-8:2022
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SIST ISO 12647-8:2022
INTERNATIONAL STANDARD ISO 12647-8:2021(E)
Graphic technology — Process control for the production
of half-tone colour separations, proof and production
prints —
Part 8:
Validation print processes working directly from digital
data
IMPORTANT — This document contains colours which are considered to be useful for the correct
understanding of the document. Users should therefore consider printing this document using a
colour printer.
1 Scope
This document specifies requirements that can be used for determining the conformance of systems
that produce a hard-copy validation print, directly from digital data, which is intended to simulate the
expected appearance of material printed in accordance with a characterized printing condition.
It is not intended for use in determining the conformance of production printing systems (digital or
conventional) since many aspects of production printing are not covered in this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
ISO 187, Paper, board and pulps — Standard atmosphere for conditioning and testing and procedure for
monitoring the atmosphere and conditioning of samples
ISO 2813, Paints and varnishes — Determination of gloss value at 20°, 60° and 85°
ISO 3664, Graphic technology and photography — Viewing conditions
ISO 8254-1, Paper and board — Measurement of specular gloss — Part 1: 75 degree gloss with a converging
beam, TAPPI method
ISO 12040, Graphic technology — Prints and printing inks — Assessment of light fastness using filtered
xenon arc light
ISO 12640-1, Graphic technology — Prepress digital data exchange — Part 1: CMYK standard colour image
data (CMYK/SCID)
ISO 12642-2, Graphic technology — Input data for characterization of 4-colour process printing — Part 2:
Expanded data set
ISO 12647-1, Graphic technology — Process control for the production of half-tone colour separations,
proof and production prints — Part 1: Parameters and measurement methods
ISO 13655:2016, Graphic technology — Spectral measurement and colorimetric computation for graphic
arts images
ISO 15397:2014, Graphic technology — Communication of graphic paper properties
© ISO 2021 – All rights reserved 1
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
ISO 15930-1, Graphic technology — Prepress digital data exchange — Use of PDF — Part 1: Complete
exchange using CMYK data (PDF/X-1 and PDF/X-1a)
ISO 15930-4, Graphic technology — Prepress digital data exchange using PDF — Part 4: Complete exchange
of CMYK and spot colour printing data using PDF 1.4 (PDF/X-1a)
ISO 15930-6, Graphic technology — Prepress digital data exchange using PDF — Part 6: Complete exchange
of printing data suitable for colour-managed workflows using PDF 1.4 (PDF/X-3)
ISO 15930-7, Graphic technology — Prepress digital data exchange using PDF — Part 7: Complete exchange
of printing data (PDF/X-4) and partial exchange of printing data with external profile reference (PDF/X-4p)
using PDF 1.6
ISO 15930-8, Graphic technology — Prepress digital data exchange using PDF — Part 8: Partial exchange
of printing data using PDF 1.6 (PDF/X-5)
ISO 15930-9, Graphic technology — Prepress digital data exchange using PDF — Part 9: Complete exchange
of printing data (PDF/X-6) and partial exchange of printing data with external profile reference (PDF/X-6p
and PDF/X-6n) using PDF 2.0
ISO/TS 18621-21, Graphic technology — Image quality evaluation methods for printed matter — Part 21:
Measurement of 1D distortions of macroscopic uniformity utilizing scanning spectrophotometers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12647-1 and the following
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
validation print substrate
substrate used for validation print processes, usually characterized by its light fastness or permanence
properties, with only essential requirements dictated by the printing process
3.2
print stabilization period
time after which the print is chemically and physically stable
Note 1 to entry: It is necessary that this property of the validation print system be specified by the manufacturer.
It is most important that the print is stable with respect to colour changes.
3.3
validation print
print produced directly from digital data early in the production chain following this document,
representative of the concept for the final product
Note 1 to entry: A validation print can have reduced accuracy compared to contract proof.
3.4
production substrate
substrate to be used for production printing, including a substrate originally intended for the validation
printing press under test
Note 1 to entry: A production substrate can be a paper with an ink receiving layer or a paper optimized for
electrophotographic printing.
2 © ISO 2021 – All rights reserved
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ISO 12647-8:2021(E)
3.5
PDF/X
title of a series of ISO standards regarding the use of the Portable Document Format (PDF) for the
dissemination of digital data intended for print reproduction
4 Requirements
4.1 Data requirements for validation print systems
Validation print systems shall accept digital data delivered as PDF/X data files in accordance with one
of the conformance levels defined in ISO 15930-1, ISO 15930-4, ISO 15930-6, ISO 15930-7, ISO 15930-8
or ISO 15930-9. Where the digital data is delivered as PDF/X data files, the intended printing condition
being simulated shall be that defined in the OutputIntents array of the PDF/X file. Where a profile is
required for data conversion, the profile that is the value of the DestOutputProfile key in the PDF/X file
shall be used. In case of multi primary based printing conditions (e.g. 5C, 6C, 7C or 8C), data should
be delivered as PDF/X-5n. Since this is currently not industrial common, the sender and receiver shall
agree on the pertinent data exchange.
NOTE There are a number of industry test suites for testing PDF/X conformance such as the Ghent PDF
[21] [23]
Output Suite 4.0 or 5.0 or the Altona Test Suite .
4.2 Validation print
4.2.1 Validation print substrate qualification
In an ideal situation, the validation print substrate should be the same as the production substrate. As
this ideal situation is seldom possible, the following criteria apply for the validation print substrate.
a) The gloss level of both the printing substrate and validation print substrate should be estimated
as one of matte, semi-matte or gloss either by the substrate manufacturer or by measuring as
described in 5.6. Matte substrates should not be used to make validation prints for gloss printing
substrates and gloss substrates should not be used to make validation prints for matte printing
substrates.
b) The white point of the unprinted validation print substrate shall allow a colorimetric match of the
substrate of the intended printing condition to be simulated with a colour difference of less than or
equal to 3,0 ΔE units when measured according to ISO 13655.
00
To assure a white point match, the validation print substrate should have a CIE L* value that is
higher than the substrate of the printing condition to be simulated.
c) The validation print substrate should belong to the same fluorescence classification as the
production substrate. Fluorescence classification in four levels of faint, low, moderate, and high
shall be made in accordance with the testing procedures described in ISO 15397:2014, 5.12.
Additional information is provided in Annex D.
4.2.2 Coloration of printed parts
4.2.2.1 Validation print system within-sheet uniformity
The variability of the coloration across the validation print format shall be verified by printing each
of the three test forms described in 5.4. Each test form shall be measured at nine locations on each
sheet as follows. Divide the printed area into thirds both horizontally and vertically and measure at
the centre of each area. All selected locations across the printed test area for each test tint, after the
stabilization period, shall have the following:
a) standard deviation less than or equal to 1,5 for CIE L*, a* and b*;
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
b) maximum ∆E colour difference less than or equal to 2 units between the average of the 9 readings
00
and any one reading.
NOTE The requirements specified in a) and b) are not statistically consistent but have been observed to be
achievable in a well-controlled digital printing system.
The uniformity shall also be measured by using the "Macro-Uniformity-Score" method defined in
ISO/TS 18621-21, also known as M-Score. Three tone value combinations specified in 5.4 shall be
evaluated as the uniformly tinted area. The "Macro-Uniformity-Score" shall be greater than or equal to
50 and should be greater than or equal to 60.
4.2.2.2 Colour simulation requirements for validation prints
The CIELAB colour coordinates of the patches of the ISO 12642-2 target and the validation print control
strip defined in 5.2 shall agree with the aim values of the printing condition being simulated as given by
the data (see 4.1) within the appropriate tolerances specified in Table 1.
NOTE 1 The colorimetric aim values for all patches are included in, or can be derived from, the colorimetric
values of the reference characterization data set.
a
Table 1 — Tolerances for reproduction of all patches in the validation print by comparison to
the values of the characterization data of the printing condition being simulated
Unit: 1
Patch in validation print form Tolerance
ΔE ≤ 3,0
Substrate
00
95th percentile: ΔE ≤ 5,0
All patches described in 5.2 (without the boundary 00
patches)
Average: ΔE ≤ 2,5
00
Average: ≤ 2,5
ΔC
h
Patches described in 5.2 c
Maximum: ≤ 4,0
ΔC
h
Selected surface gamut patches as listed in Annex C
Average: ΔE ≤ 3,0
00
(taken from ISO 12642-2)
Average: ΔE ≤ 2,5
00
b
All patches described in ISO 12642-2
95th percentile: ΔE ≤ 5,0
00
ΔE ≤ 3,5
Spot colours (solids)
00
a
Described in Clause 5.
b
For multicolour reference printing conditions, only the patches in 5.2 shall be used.
These tolerances apply only to conformance of validation prints as defined in A.1 and A.2. They can also
be used for validation prints made for a particular printing condition when tested in the field using only
a control wedge. They might be inappropriate as tolerances for daily use at production sites due to the
increased production costs required to maintain the equipment in this optimum state.
NOTE 2 It is expected that validation printing system can also reproduce solid spot colours, provided that a
clear identification by the CIELAB colour or spectral definition such as ISO 17972-4 (CxF/X-4).
NOTE 3 Only when spot colour availability is declared, the declared spot colours are evaluated.
4.2.3 Short- and long-term repeatability
Three validation prints containing at least the primary and CMY secondary colour solids, and primary
colour mid-tones shall be produced. There shall be a 1 hour time difference between the production of
the first and second print and a one day time difference between the first and third validation print.
Recalibration before production of each print is permitted. For each print, measurements shall be made
on the first print produced after the vendor-specified stabilization period. The maximum CIEDE2000
4 © ISO 2021 – All rights reserved
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
CIELAB colour difference between any two of the three samples of each colour shall not exceed the
values shown in Table 2.
Table 2 — Repeatability of primary and CMY secondary colour solids
and primary colour mid-tones (CIEDE2000 -colour differences)
Unit: 1
Mid-tones
Type Solids
(40 % to 50 %)
Validation print 2,0 2,5
NOTE For certain print systems, the same point on a validation print can be formed from a different source
on different days; strictly speaking, this is testing reproducibility not repeatability. For these systems, there is no
true test of repeatability.
4.2.4 Permanence
4.2.4.1 Print stabilization period
A test should be performed and reported to verify that the print colorant has sufficient resistance to
a defined mechanical abrasion after any manufacturer's defined stabilization period. One optional
test method is specified in Annex B. In any test, the time required for the validation print solids to
reach mechanical stability should not exceed the manufacturer’s defined stabilization period. In the
case that there is no manufacturer’s defined stabilization period, it should not exceed 30 min. This
test should be performed for each separate combination of materials, driving software, colorant and
printing condition that potentially can change the print stabilization time. If the validation print has
been coated, this shall be reported.
4.2.4.2 Fading and light fastness testing
Fading testing shall use the solid tones of the C, M ,Y ,R ,G ,B plus K (7 patches). The measurement
condition shall be in accordance with ISO 13655:2016, M1 with white backing. Colorimetric calculation
shall be in accordance with ISO 13655.
The validation print stabilization period shall be specified by the manufacturer. The variability
(“fading”) of the C ,M ,Y ,R ,G ,B plus K patches over time, in the dark, shall not exceed 1,5 ∆E colour
00
difference units during the first 24 hours after the print stabilization period.
Four copies of a test form shall be prepared on the validation print substrate, which contain unprinted
parts and patches of printed primaries and CMY secondaries both as solids and as midtones.
Combinations of all of the process colours used by the validation printing system shall be included in
this set, which may include more than four colorants.
Three copies of the test form shall be stored for a print stabilisation period of at least 24 h in the dark
under standard atmosphere according to ISO 187 (at 23 °C ± 1 °C and a relative humidity of 50 % ± 2 %
RH).
The CIELAB colour values of the validation printing substrate and the printed patches shall be measured
according to ISO 13655 M0, M1 or M2 on white backing.
Each of the three copies of the test form shall be subjected to one of the following storage conditions.
a) 24 h at 25 °C ± 1 °C and at a relative humidity of 25 % ± 2 % in the dark.
b) 24 h at 40 °C ± 1 °C and at a relative humidity of 80 % ± 2 % in the dark.
c) One week at 40 °C ± 1 °C and at a relative humidity of 10 % ± 2 % in the dark.
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SIST ISO 12647-8:2022
ISO 12647-8:2021(E)
For each of these treatments, for the substrate and for all patches of the test form the maximum colour
difference between
...
INTERNATIONAL ISO
STANDARD 12647-8
Second edition
2021-05
Graphic technology — Process control
for the production of half-tone colour
separations, proof and production
prints —
Part 8:
Validation print processes working
directly from digital data
Technologie graphique — Contrôle des processus de confection de
sélections couleurs tramées, d'épreuves et de tirages —
Partie 8: Processus d'impression de maquette couleur produite à
partir de données numériques
Reference number
ISO 12647-8:2021(E)
©
ISO 2021
---------------------- Page: 1 ----------------------
ISO 12647-8:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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 2021 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 12647-8:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Requirements . 3
4.1 Data requirements for validation print systems . 3
4.2 Validation print . 3
4.2.1 Validation print substrate qualification . 3
4.2.2 Coloration of printed parts . 3
4.2.3 Short- and long-term repeatability . 4
4.2.4 Permanence . . 5
4.2.5 Ink set gloss . 6
4.2.6 Tone value reproduction limits . 6
4.2.7 Tonality assessment . 6
4.2.8 Reproduction of vignettes . 6
4.2.9 Image resolving power . 7
4.2.10 Margin information . 7
5 Test methods . 8
5.1 System validation . 8
5.2 Validation print control strip . 8
5.3 Additional test objects . 8
5.4 Uniformity measurement . 9
5.5 Colour measurement . 9
5.6 Measurement of gloss . 9
5.7 Supplementary visual control element . 9
Annex A (normative) Technical requirements for validation print conformity .10
Annex B (informative) Determination of print durability after stabilization .12
Annex C (normative) Surface gamut patches .15
Annex D (informative) Categorising fluorescence .21
Bibliography .22
© ISO 2021 – All rights reserved iii
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ISO 12647-8:2021(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 130, Graphic technology.
This second edition cancels and replaces the first edition (ISO 12647-8:2012), which has been
technically revised.
The main changes compared to the previous edition are as follows:
*
— CIE 1976 ∆E has been replaced with modern ∆E colour difference formulae;
ab 00
— a better metric for uniformity assessment, namely the measurement of 1D distortions of macroscopic
uniformity utilizing scanning spectrophotometers, has been added;
— a more content oriented control wedge has been added;
— a new Annex A has been added to align the content with ISO 12647-7, with respect to substrate
categorisation and conformance assessment;
— informative metrics that proved to be not practical, such as tonality, have been deleted.
A list of all parts in the ISO 12647 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 2021 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 12647-8:2021(E)
Introduction
This document specifies the properties, and associated test methods, required for digital prints and
printing processes to meet the criteria established for “validation prints”.
In most printing workflows, there is a requirement for a visual representation of the expected
appearance of the document being printed that can be used as part of the agreement between customer
and printer. Where this visual representation is produced such that its characteristics (colour fidelity,
tone reproduction, registration, size, etc.) simulate those of the expected printing within tight
tolerances, it is usually referred to as a “contract proof”. As the name implies, contract proofs are used as
part of the contractual relationship between customer and printer and are used as a visual aim for the
press operator during printing as well as the absolute reference against which the finished production
is compared. Not unexpectedly, systems that can produce contract proofs are usually expensive and
require careful operation and maintenance. ISO 12647-7 specifies the requirements for contract proofs
and systems used to produce contract proofs directly from digital data.
Recently, other visualizations of the final printed product have found a place in the printing/proofing
workflow because designers and print buyers prefer not to go to the expense of using an ISO 12647-7
compliant contract proof any earlier in the process than necessary. In many situations, participants in
the workflow require a hardcopy visual reference of lesser quality than a contract proof. In the past,
those prints varied widely in quality and were often referred to as design proofs, concept proofs, layout
prints, etc. That quality level is here being referred to as a “validation print”.
Because data are exchanged electronically, and visualizations of those data are produced at multiple
sites, there is a requirement for defined requirements for validation prints to allow a degree of
consistency throughout the workflow. One of the goals of having less stringent requirements,
particularly on colour fidelity, is to allow the production of validation prints on less elaborate and less
costly devices than are required for contract proofs. The requirements for validation prints and the
systems used to produce validation prints are given in this document.
Validation prints are not intended to replace “contract proofs” for predicting colour on production
printing devices. It is expected that the modifications of the requirements for validation prints, along
with the requirements for contract proofs, will continue in the future as industry requirements and
imaging technologies develop.
© ISO 2021 – All rights reserved v
---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 12647-8:2021(E)
Graphic technology — Process control for the production
of half-tone colour separations, proof and production
prints —
Part 8:
Validation print processes working directly from digital
data
IMPORTANT — This document contains colours which are considered to be useful for the correct
understanding of the document. Users should therefore consider printing this document using a
colour printer.
1 Scope
This document specifies requirements that can be used for determining the conformance of systems
that produce a hard-copy validation print, directly from digital data, which is intended to simulate the
expected appearance of material printed in accordance with a characterized printing condition.
It is not intended for use in determining the conformance of production printing systems (digital or
conventional) since many aspects of production printing are not covered in this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
ISO 187, Paper, board and pulps — Standard atmosphere for conditioning and testing and procedure for
monitoring the atmosphere and conditioning of samples
ISO 2813, Paints and varnishes — Determination of gloss value at 20°, 60° and 85°
ISO 3664, Graphic technology and photography — Viewing conditions
ISO 8254-1, Paper and board — Measurement of specular gloss — Part 1: 75 degree gloss with a converging
beam, TAPPI method
ISO 12040, Graphic technology — Prints and printing inks — Assessment of light fastness using filtered
xenon arc light
ISO 12640-1, Graphic technology — Prepress digital data exchange — Part 1: CMYK standard colour image
data (CMYK/SCID)
ISO 12642-2, Graphic technology — Input data for characterization of 4-colour process printing — Part 2:
Expanded data set
ISO 12647-1, Graphic technology — Process control for the production of half-tone colour separations,
proof and production prints — Part 1: Parameters and measurement methods
ISO 13655:2016, Graphic technology — Spectral measurement and colorimetric computation for graphic
arts images
ISO 15397:2014, Graphic technology — Communication of graphic paper properties
© ISO 2021 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO 12647-8:2021(E)
ISO 15930-1, Graphic technology — Prepress digital data exchange — Use of PDF — Part 1: Complete
exchange using CMYK data (PDF/X-1 and PDF/X-1a)
ISO 15930-4, Graphic technology — Prepress digital data exchange using PDF — Part 4: Complete exchange
of CMYK and spot colour printing data using PDF 1.4 (PDF/X-1a)
ISO 15930-6, Graphic technology — Prepress digital data exchange using PDF — Part 6: Complete exchange
of printing data suitable for colour-managed workflows using PDF 1.4 (PDF/X-3)
ISO 15930-7, Graphic technology — Prepress digital data exchange using PDF — Part 7: Complete exchange
of printing data (PDF/X-4) and partial exchange of printing data with external profile reference (PDF/X-4p)
using PDF 1.6
ISO 15930-8, Graphic technology — Prepress digital data exchange using PDF — Part 8: Partial exchange
of printing data using PDF 1.6 (PDF/X-5)
ISO 15930-9, Graphic technology — Prepress digital data exchange using PDF — Part 9: Complete exchange
of printing data (PDF/X-6) and partial exchange of printing data with external profile reference (PDF/X-6p
and PDF/X-6n) using PDF 2.0
ISO/TS 18621-21, Graphic technology — Image quality evaluation methods for printed matter — Part 21:
Measurement of 1D distortions of macroscopic uniformity utilizing scanning spectrophotometers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12647-1 and the following
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
validation print substrate
substrate used for validation print processes, usually characterized by its light fastness or permanence
properties, with only essential requirements dictated by the printing process
3.2
print stabilization period
time after which the print is chemically and physically stable
Note 1 to entry: It is necessary that this property of the validation print system be specified by the manufacturer.
It is most important that the print is stable with respect to colour changes.
3.3
validation print
print produced directly from digital data early in the production chain following this document,
representative of the concept for the final product
Note 1 to entry: A validation print can have reduced accuracy compared to contract proof.
3.4
production substrate
substrate to be used for production printing, including a substrate originally intended for the validation
printing press under test
Note 1 to entry: A production substrate can be a paper with an ink receiving layer or a paper optimized for
electrophotographic printing.
2 © ISO 2021 – All rights reserved
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ISO 12647-8:2021(E)
3.5
PDF/X
title of a series of ISO standards regarding the use of the Portable Document Format (PDF) for the
dissemination of digital data intended for print reproduction
4 Requirements
4.1 Data requirements for validation print systems
Validation print systems shall accept digital data delivered as PDF/X data files in accordance with one
of the conformance levels defined in ISO 15930-1, ISO 15930-4, ISO 15930-6, ISO 15930-7, ISO 15930-8
or ISO 15930-9. Where the digital data is delivered as PDF/X data files, the intended printing condition
being simulated shall be that defined in the OutputIntents array of the PDF/X file. Where a profile is
required for data conversion, the profile that is the value of the DestOutputProfile key in the PDF/X file
shall be used. In case of multi primary based printing conditions (e.g. 5C, 6C, 7C or 8C), data should
be delivered as PDF/X-5n. Since this is currently not industrial common, the sender and receiver shall
agree on the pertinent data exchange.
NOTE There are a number of industry test suites for testing PDF/X conformance such as the Ghent PDF
[21] [23]
Output Suite 4.0 or 5.0 or the Altona Test Suite .
4.2 Validation print
4.2.1 Validation print substrate qualification
In an ideal situation, the validation print substrate should be the same as the production substrate. As
this ideal situation is seldom possible, the following criteria apply for the validation print substrate.
a) The gloss level of both the printing substrate and validation print substrate should be estimated
as one of matte, semi-matte or gloss either by the substrate manufacturer or by measuring as
described in 5.6. Matte substrates should not be used to make validation prints for gloss printing
substrates and gloss substrates should not be used to make validation prints for matte printing
substrates.
b) The white point of the unprinted validation print substrate shall allow a colorimetric match of the
substrate of the intended printing condition to be simulated with a colour difference of less than or
equal to 3,0 ΔE units when measured according to ISO 13655.
00
To assure a white point match, the validation print substrate should have a CIE L* value that is
higher than the substrate of the printing condition to be simulated.
c) The validation print substrate should belong to the same fluorescence classification as the
production substrate. Fluorescence classification in four levels of faint, low, moderate, and high
shall be made in accordance with the testing procedures described in ISO 15397:2014, 5.12.
Additional information is provided in Annex D.
4.2.2 Coloration of printed parts
4.2.2.1 Validation print system within-sheet uniformity
The variability of the coloration across the validation print format shall be verified by printing each
of the three test forms described in 5.4. Each test form shall be measured at nine locations on each
sheet as follows. Divide the printed area into thirds both horizontally and vertically and measure at
the centre of each area. All selected locations across the printed test area for each test tint, after the
stabilization period, shall have the following:
a) standard deviation less than or equal to 1,5 for CIE L*, a* and b*;
© ISO 2021 – All rights reserved 3
---------------------- Page: 8 ----------------------
ISO 12647-8:2021(E)
b) maximum ∆E colour difference less than or equal to 2 units between the average of the 9 readings
00
and any one reading.
NOTE The requirements specified in a) and b) are not statistically consistent but have been observed to be
achievable in a well-controlled digital printing system.
The uniformity shall also be measured by using the "Macro-Uniformity-Score" method defined in
ISO/TS 18621-21, also known as M-Score. Three tone value combinations specified in 5.4 shall be
evaluated as the uniformly tinted area. The "Macro-Uniformity-Score" shall be greater than or equal to
50 and should be greater than or equal to 60.
4.2.2.2 Colour simulation requirements for validation prints
The CIELAB colour coordinates of the patches of the ISO 12642-2 target and the validation print control
strip defined in 5.2 shall agree with the aim values of the printing condition being simulated as given by
the data (see 4.1) within the appropriate tolerances specified in Table 1.
NOTE 1 The colorimetric aim values for all patches are included in, or can be derived from, the colorimetric
values of the reference characterization data set.
a
Table 1 — Tolerances for reproduction of all patches in the validation print by comparison to
the values of the characterization data of the printing condition being simulated
Unit: 1
Patch in validation print form Tolerance
ΔE ≤ 3,0
Substrate
00
95th percentile: ΔE ≤ 5,0
All patches described in 5.2 (without the boundary 00
patches)
Average: ΔE ≤ 2,5
00
Average: ≤ 2,5
ΔC
h
Patches described in 5.2 c
Maximum: ≤ 4,0
ΔC
h
Selected surface gamut patches as listed in Annex C
Average: ΔE ≤ 3,0
00
(taken from ISO 12642-2)
Average: ΔE ≤ 2,5
00
b
All patches described in ISO 12642-2
95th percentile: ΔE ≤ 5,0
00
ΔE ≤ 3,5
Spot colours (solids)
00
a
Described in Clause 5.
b
For multicolour reference printing conditions, only the patches in 5.2 shall be used.
These tolerances apply only to conformance of validation prints as defined in A.1 and A.2. They can also
be used for validation prints made for a particular printing condition when tested in the field using only
a control wedge. They might be inappropriate as tolerances for daily use at production sites due to the
increased production costs required to maintain the equipment in this optimum state.
NOTE 2 It is expected that validation printing system can also reproduce solid spot colours, provided that a
clear identification by the CIELAB colour or spectral definition such as ISO 17972-4 (CxF/X-4).
NOTE 3 Only when spot colour availability is declared, the declared spot colours are evaluated.
4.2.3 Short- and long-term repeatability
Three validation prints containing at least the primary and CMY secondary colour solids, and primary
colour mid-tones shall be produced. There shall be a 1 hour time difference between the production of
the first and second print and a one day time difference between the first and third validation print.
Recalibration before production of each print is permitted. For each print, measurements shall be made
on the first print produced after the vendor-specified stabilization period. The maximum CIEDE2000
4 © ISO 2021 – All rights reserved
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ISO 12647-8:2021(E)
CIELAB colour difference between any two of the three samples of each colour shall not exceed the
values shown in Table 2.
Table 2 — Repeatability of primary and CMY secondary colour solids
and primary colour mid-tones (CIEDE2000 -colour differences)
Unit: 1
Mid-tones
Type Solids
(40 % to 50 %)
Validation print 2,0 2,5
NOTE For certain print systems, the same point on a validation print can be formed from a different source
on different days; strictly speaking, this is testing reproducibility not repeatability. For these systems, there is no
true test of repeatability.
4.2.4 Permanence
4.2.4.1 Print stabilization period
A test should be performed and reported to verify that the print colorant has sufficient resistance to
a defined mechanical abrasion after any manufacturer's defined stabilization period. One optional
test method is specified in Annex B. In any test, the time required for the validation print solids to
reach mechanical stability should not exceed the manufacturer’s defined stabilization period. In the
case that there is no manufacturer’s defined stabilization period, it should not exceed 30 min. This
test should be performed for each separate combination of materials, driving software, colorant and
printing condition that potentially can change the print stabilization time. If the validation print has
been coated, this shall be reported.
4.2.4.2 Fading and light fastness testing
Fading testing shall use the solid tones of the C, M ,Y ,R ,G ,B plus K (7 patches). The measurement
condition shall be in accordance with ISO 13655:2016, M1 with white backing. Colorimetric calculation
shall be in accordance with ISO 13655.
The validation print stabilization period shall be specified by the manufacturer. The variability
(“fading”) of the C ,M ,Y ,R ,G ,B plus K patches over time, in the dark, shall not exceed 1,5 ∆E colour
00
difference units during the first 24 hours after the print stabilization period.
Four copies of a test form shall be prepared on the validation print substrate, which contain unprinted
parts and patches of printed primaries and CMY secondaries both as solids and as midtones.
Combinations of all of the process colours used by the validation printing system shall be included in
this set, which may include more than four colorants.
Three copies of the test form shall be stored for a print stabilisation period of at least 24 h in the dark
under standard atmosphere according to ISO 187 (at 23 °C ± 1 °C and a relative humidity of 50 % ± 2 %
RH).
The CIELAB colour values of the validation printing substrate and the printed patches shall be measured
according to ISO 13655 M0, M1 or M2 on white backing.
Each of the three copies of the test form shall be subjected to one of the following storage conditions.
a) 24 h at 25 °C ± 1 °C and at a relative humidity of 25 % ± 2 % in the dark.
b) 24 h at 40 °C ± 1 °C and at a relative humidity of 80 % ± 2 % in the dark.
c) One week at 40 °C ± 1 °C and at a relative humidity of 10 % ± 2 % in the dark.
© ISO 2021 – All rights reserved 5
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ISO 12647-8:2021(E)
For each of these treatments, for the substrate and for all patches of the test form the maximum colour
difference between colour values of the patches before and after the treatment shall not exceed 4,5
ΔE units.
00
In cases where validation prints are expected to be used for a longer period of time, light fastness
exposure shall be performed using a window glass filtered xenon lamp. It shall meet a light fastness
rating of 3 or greater using the blue wool test as described in ISO 12040. This corresponds to a dose of
2
43 000 kJ/m and a colour difference of ΔE < 4,5.
00
NOTE 1 Production printing substrates with OBAs are usually less stable than typical inkjet-based validation
printing substrates. However, in this case, it is expected that the validation print is stable over time and does
not reflect this specific behaviour. It is expected that a typical validation print is not used longer than 3 months,
hence a lightfastness test is only informative.
[1]
NOTE 2 It is anticipated that window glass application as described in ISO 105-B02 , such as optical filters,
be fitted to minimize short-wavelength light (less than 310 nm).
[15]
NOTE 3 For further information or alternative methods on light fastness testing, see ISO 18937 and
[16]
ISO 21139-1 . These International Standards have been recently published and are subject for future use in
this document.
4.2.5 Ink set gloss
The gloss of solid tone colours should be similar to that of the production print to be simulated. The ink
set gloss may be specified if deemed
...
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 12647-8
ISO/TC 130
Graphic technology — Process control
Secretariat: SAC
for the production of half-tone colour
Voting begins on:
2021-02-24 separations, proof and production
prints —
Voting terminates on:
2021-04-21
Part 8:
Validation print processes working
directly from digital data
Technologie graphique — Contrôle des processus de confection de
sélections couleurs tramées, d'épreuves et de tirages —
Partie 8: Processus d'impression de maquette couleur produite à
partir de données numériques
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 12647-8:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2021
---------------------- Page: 1 ----------------------
ISO/FDIS 12647-8:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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 2021 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/FDIS 12647-8:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Requirements . 3
4.1 Data requirements for validation print systems . 3
4.2 Validation print . 3
4.2.1 Validation print substrate qualification . 3
4.2.2 Coloration of printed parts . 3
4.2.3 Short- and long-term repeatability . 4
4.2.4 Permanence . . 5
4.2.5 Ink set gloss . 6
4.2.6 Tone value reproduction limits . 6
4.2.7 Tonality assessment . 6
4.2.8 Reproduction of vignettes . 6
4.2.9 Image resolving power . 7
4.2.10 Margin information . 7
5 Test methods . 8
5.1 System validation . 8
5.2 Validation print control strip . 8
5.3 Additional test objects . 8
5.4 Uniformity measurement . 9
5.5 Colour measurement . 9
5.6 Measurement of gloss . 9
5.7 Supplementary visual control element . 9
Annex A (normative) Technical requirements for validation print conformity .10
Annex B (informative) Determination of print durability after stabilization .12
Annex C (normative) Surface gamut patches .15
Annex D (informative) Categorising fluorescence .21
Bibliography .22
© ISO 2021 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/FDIS 12647-8:2021(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 130, Graphic technology.
This second edition cancels and replaces the first edition (ISO 12647-8:2012), which has been
technically revised.
The main changes compared to the previous edition are as follows:
*
— CIE 1976 ∆E has been replaced with modern ∆E colour difference formulae;
ab 00
— a better metric for uniformity assessment, namely the measurement of 1D distortions of macroscopic
uniformity utilizing scanning spectrophotometers, has been added;
— a more content oriented control wedge has been added;
— a new Annex A has been added to align the content with ISO 12647-7, with respect to substrate
categorisation and conformance assessment;
— informative metrics that proved to be not practical, such as tonality, have been deleted.
A list of all parts in the ISO 12647 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 2021 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/FDIS 12647-8:2021(E)
Introduction
This document specifies the properties, and associated test methods, required for digital prints and
printing processes to meet the criteria established for “validation prints”.
In most printing workflows, there is a requirement for a visual representation of the expected
appearance of the document being printed that can be used as part of the agreement between customer
and printer. Where this visual representation is produced such that its characteristics (colour fidelity,
tone reproduction, registration, size, etc.) simulate those of the expected printing within tight
tolerances, it is usually referred to as a “contract proof”. As the name implies, contract proofs are used as
part of the contractual relationship between customer and printer and are used as a visual aim for the
press operator during printing as well as the absolute reference against which the finished production
is compared. Not unexpectedly, systems that can produce contract proofs are usually expensive and
require careful operation and maintenance. ISO 12647-7 specifies the requirements for contract proofs
and systems used to produce contract proofs directly from digital data.
Recently, other visualizations of the final printed product have found a place in the printing/proofing
workflow because designers and print buyers prefer not to go to the expense of using an ISO 12647-7
compliant contract proof any earlier in the process than necessary. In many situations, participants in
the workflow require a hardcopy visual reference of lesser quality than a contract proof. In the past,
those prints varied widely in quality and were often referred to as design proofs, concept proofs, layout
prints, etc. That quality level is here being referred to as a “validation print”.
Because data are exchanged electronically, and visualizations of those data are produced at multiple
sites, there is a requirement for defined requirements for validation prints to allow a degree of
consistency throughout the workflow. One of the goals of having less stringent requirements,
particularly on colour fidelity, is to allow the production of validation prints on less elaborate and less
costly devices than are required for contract proofs. The requirements for validation prints and the
systems used to produce validation prints are given in this document.
Validation prints are not intended to replace “contract proofs” for predicting colour on production
printing devices. It is expected that the modifications of the requirements for validation prints, along
with the requirements for contract proofs, will continue in the future as industry requirements and
imaging technologies develop.
© ISO 2021 – All rights reserved v
---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 12647-8:2021(E)
Graphic technology — Process control for the production
of half-tone colour separations, proof and production
prints —
Part 8:
Validation print processes working directly from digital data
IMPORTANT — This document contains colours which are considered to be useful for the correct
understanding of the document. Users should therefore consider printing this document using a
colour printer.
1 Scope
This document specifies requirements that can be used for determining the conformance of systems
that produce a hard-copy validation print, directly from digital data, which is intended to simulate the
expected appearance of material printed in accordance with a characterized printing condition.
It is not intended for use in determining the conformance of production printing systems (digital or
conventional) since many aspects of production printing are not covered in this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
ISO 187, Paper, board and pulps — Standard atmosphere for conditioning and testing and procedure for
monitoring the atmosphere and conditioning of samples
ISO 2813, Paints and varnishes — Determination of gloss value at 20°, 60° and 85°
ISO 3664, Graphic technology and photography — Viewing conditions
ISO 8254-1, Paper and board — Measurement of specular gloss — Part 1: 75 degree gloss with a converging
beam, TAPPI method
ISO 12040, Graphic technology — Prints and printing inks — Assessment of light fastness using filtered
xenon arc light
ISO 12640-1, Graphic technology — Prepress digital data exchange — Part 1: CMYK standard colour image
data (CMYK/SCID)
ISO 12642-2, Graphic technology — Input data for characterization of 4-colour process printing — Part 2:
Expanded data set
ISO 12647-1, Graphic technology — Process control for the production of half-tone colour separations,
proof and production prints — Part 1: Parameters and measurement methods
ISO 13655:2016, Graphic technology — Spectral measurement and colorimetric computation for graphic
arts images
ISO 15397:2014, Graphic technology — Communication of graphic paper properties
© ISO 2021 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO/FDIS 12647-8:2021(E)
ISO 15930-1, Graphic technology — Prepress digital data exchange — Use of PDF — Part 1: Complete
exchange using CMYK data (PDF/X-1 and PDF/X-1a)
ISO 15930-4, Graphic technology — Prepress digital data exchange using PDF — Part 4: Complete exchange
of CMYK and spot colour printing data using PDF 1.4 (PDF/X-1a)
ISO 15930-6, Graphic technology — Prepress digital data exchange using PDF — Part 6: Complete exchange
of printing data suitable for colour-managed workflows using PDF 1.4 (PDF/X-3)
ISO 15930-7, Graphic technology — Prepress digital data exchange using PDF — Part 7: Complete exchange
of printing data (PDF/X-4) and partial exchange of printing data with external profile reference (PDF/X-4p)
using PDF 1.6
ISO 15930-8, Graphic technology — Prepress digital data exchange using PDF — Part 8: Partial exchange
of printing data using PDF 1.6 (PDF/X-5)
ISO 15930-9, Graphic technology — Prepress digital data exchange using PDF — Part 9: Complete exchange
of printing data (PDF/X-6) and partial exchange of printing data with external profile reference (PDF/X-6p
and PDF/X-6n) using PDF 2.0
ISO/TS 18621-21, Graphic technology — Image quality evaluation methods for printed matter — Part 21:
Measurement of 1D distortions of macroscopic uniformity utilizing scanning spectrophotometers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12647-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
validation print substrate
substrate used for validation print processes, usually characterized by its light fastness or permanence
properties, with only essential requirements dictated by the printing process
3.2
print stabilization period
time after which the print is chemically and physically stable
Note 1 to entry: It is necessary that this property of the validation print system be specified by the manufacturer.
It is most important that the print is stable with respect to colour changes.
3.3
validation print
print produced directly from digital data early in the production chain following this document,
representative of the concept for the final product
Note 1 to entry: A validation print can have reduced accuracy compared to contract proof.
3.4
production substrate
substrate to be used for production printing, including a substrate originally intended for the validation
printing press under test
Note 1 to entry: A production substrate can be a paper with an ink receiving layer or a paper optimized for
electrophotographic printing.
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ISO/FDIS 12647-8:2021(E)
3.5
PDF/X
title of a series of ISO standards regarding the use of the Portable Document Format (PDF) for the
dissemination of digital data intended for print reproduction
4 Requirements
4.1 Data requirements for validation print systems
Validation print systems shall accept digital data delivered as PDF/X data files in accordance with one
of the conformance levels defined in ISO 15930-1, ISO 15930-4, ISO 15930-6, ISO 15930-7, ISO 15930-8
or ISO 15930-9. Where the digital data is delivered as PDF/X data files, the intended printing condition
being simulated shall be that defined in the OutputIntents array of the PDF/X file. Where a profile is
required for data conversion, the profile that is the value of the DestOutputProfile key in the PDF/X file
shall be used. In case of multi primary based printing conditions (e.g. 5C, 6C, 7C or 8C), data should
be delivered as PDF/X-5n. Since this is currently not industrial common, the sender and receiver shall
agree on the pertinent data exchange.
NOTE There are a number of industry test suites for testing PDF/X conformance such as The Ghent PDF
[21] [23]
Output Suite 4,0 or 5,0 or the Altona Test Suite .
4.2 Validation print
4.2.1 Validation print substrate qualification
In an ideal situation, the validation print substrate should be the same as the production substrate. As
this ideal situation is seldom possible, the following criteria apply for the validation print substrate.
a) The gloss level of both the printing substrate and validation print substrate should be estimated
as one of matte, semi-matte or gloss either by the substrate manufacturer or by measuring as
described in 5.6. Matte substrates should not be used to make validation prints for gloss printing
substrates and gloss substrates should not be used to make validation prints for matte printing
substrates.
b) The white point of the unprinted validation print substrate shall allow a colorimetric match of the
substrate of the intended printing condition to be simulated with a colour difference of less than or
equal to 3,0 ΔE units when measured according to ISO 13655.
00
To assure a white point match, the validation print substrate should have a CIE L* value that is
higher than the substrate of the printing condition to be simulated.
c) The validation print substrate should belong to the same fluorescence classification as the
production substrate. Fluorescence classification in four levels of faint, low, moderate, and high
shall be made in accordance with the testing procedures described in ISO 15397:2014, 5.12.
Additional information is provided in Annex D.
4.2.2 Coloration of printed parts
4.2.2.1 Validation print system within-sheet uniformity
The variability of the coloration across the validation print format shall be verified by printing each
of the three test forms described in 5.4. Each test form shall be measured at nine locations on each
sheet as follows. Divide the printed area into thirds both horizontally and vertically and measure at
the centre of each area. All selected locations across the printed test area for each test tint, after the
stabilization period, shall have the following:
a) standard deviation less than or equal to 1,5 for CIE L*, a* and b*;
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ISO/FDIS 12647-8:2021(E)
b) maximum ∆E colour difference less than or equal to 2 units between the average of the 9 readings
00
and any one reading.
NOTE The requirements specified in a) and b) are not statistically consistent but have been observed to be
achievable in a well-controlled digital printing system.
The uniformity shall also be measured by using the "Macro-Uniformity-Score" method defined in
ISO/TS 18621-21, also known as M-Score. Three tone value combinations specified in 5.4 shall be
evaluated as the uniformly tinted area. The "Macro-Uniformity-Score" shall be greater than or equal to
50 and should be greater than or equal to 60.
4.2.2.2 Colour simulation requirements for validation prints
The CIELAB colour coordinates of the patches of the ISO 12642-2 target and the validation print control
strip defined in 5.2 shall agree with the aim values of the printing condition being simulated as given by
the data (see 4.1) within the appropriate tolerances specified in Table 2.
NOTE 1 The colorimetric aim values for all patches are included in, or can be derived from, the colorimetric
values of the reference characterization data set.
a
Table 2 — Tolerances for reproduction of all patches in the validation print by comparison to
the values of the characterization data of the printing condition being simulated
Unit: 1
Patch in validation print form Tolerance
ΔE ≤ 3,0
Substrate
00
95th percentile: ΔE ≤ 5,0
All patches described in 5.2 (without the boundary 00
patches)
Average: ΔE ≤ 2,5
00
Average: ≤ 2,5
ΔC
h
Patches described in 5.2 c
Maximum: ≤ 4,0
ΔC
h
Selected surface gamut patches as listed in Annex C
Average: ΔE ≤ 3,0
00
(taken from ISO 12642-2)
Average: ΔE ≤ 2,5
00
b
All patches described in ISO 12642-2
95th percentile: ΔE ≤ 5,0
00
ΔE ≤ 3,5
Spot colours (solids)
00
a
Described in Clause 5.
b
For multicolour reference printing conditions, only the patches in 5.2 shall be used.
These tolerances apply only to conformance of validation prints as defined in A.1 and A.2. They can also
be used for validation prints made for a particular printing condition when tested in the field using only
a control wedge. They might be inappropriate as tolerances for daily use at production sites due to the
increased production costs required to maintain the equipment in this optimum state.
NOTE 2 It is expected that validation printing system can also reproduce solid spot colours, provided that a
clear identification by the CIELAB colour or spectral definition such as ISO 17972-4 (CxF/X-4).
NOTE 3 Only when spot colour availability is declared, the declared spot colours are evaluated.
4.2.3 Short- and long-term repeatability
Three validation prints containing at least the primary and CMY secondary colour solids, and primary
colour mid-tones shall be produced. There shall be a 1 hour time difference between the production of
the first and second print and a one day time difference between the first and third validation print.
Recalibration before production of each print is permitted. For each print, measurements shall be made
on the first print produced after the vendor-specified stabilization period. The maximum CIEDE2000
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ISO/FDIS 12647-8:2021(E)
CIELAB colour difference between any two of the three samples of each colour shall not exceed the
values shown in Table 3.
Table 3 — Repeatability of primary and CMY secondary colour solids
and primary colour mid-tones (CIEDE2000 -colour differences)
Unit: 1
Mid-tones
Type Solids
(40 % to 50 %)
Validation print 2,0 2,5
NOTE For certain print systems, the same point on a validation print can be formed from a different source
on different days; strictly speaking, this is testing reproducibility not repeatability. For these systems, there is no
true test of repeatability.
4.2.4 Permanence
4.2.4.1 Print stabilization period
A test should be performed and reported to verify that the print colorant has sufficient resistance to
a defined mechanical abrasion after any manufacturer's defined stabilization period. One optional
test method is specified in Annex B. In any test, the time required for the validation print solids to
reach mechanical stability should not exceed the manufacturer’s defined stabilization period. In the
case that there is no manufacturer’s defined stabilization period, it should not exceed 30 min. This
test should be performed for each separate combination of materials, driving software, colorant and
printing condition that potentially can change the print stabilization time. If the validation print has
been coated, this shall be reported.
4.2.4.2 Fading and light fastness testing
Fading testing shall use the solid tones of the C, M ,Y ,R ,G ,B plus K (7 patches). The measurement
condition shall be in accordance with ISO 13655:2016, M1 with white backing. Colorimetric calculation
shall be in accordance with ISO 13655.
The validation print stabilization period shall be specified by the manufacturer. The variability
(“fading”) of the C ,M ,Y ,R ,G ,B plus K patches over time, in the dark, shall not exceed 1,5 ∆E colour
00
difference units during the first 24 hours after the print stabilization period.
Four copies of a test form shall be prepared on the validation print substrate, which contain unprinted
parts and patches of printed primaries and CMY secondaries both as solids and as midtones.
Combinations of all of the process colours used by the validation printing system shall be included in
this set, which may include more than four colorants.
Three copies of the test form shall be stored for a print stabilisation period of at least 24 h in the
dark under standard atmosphere according to ISO 187 (at 23 °C ± 1 °C and a relative humidity of
50 % ± 2 % RH).
The CIELAB colour values of the validation printing substrate and the printed patches shall be measured
according to ISO 13655 M0, M1 or M2 on white backing.
Each of the three copies of the test form shall be subjected to one of the following storage conditions.
a) 24 h at 25 °C ± 1 °C and at a relative humidity of 25 % ± 2 % in the dark.
b) 24 h at 40 °C ± 1 °C and at a relative humidity of 80 % ± 2 % in the dark.
c) One week at 40 °C ± 1 °C and at a relative humidity of 10 % ± 2 % in the dark.
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ISO/FDIS 12647-8:2021(E)
For each of these treatments, for the substrate and for all patches of the test form the maximum colour
difference between colour values of the patches before and after the treatment shall not exceed 4,5
ΔE units.
00
In cases where validation prints are expected to be used for a longer period of time, light fastness
exposure shall be performed using a window glass filtered xenon lamp. It shall meet a light fastness
rating of 3 or greater using the blue wool test as described in ISO 12040. This corresponds to a dose of
2
43 000 kJ/m and a colour difference of ΔE < 4,5.
00
NOTE 1 Production printing substrates with OVAs are usually less stable than typical inkjet-based validation
printing substrates. However, in this case, it is expected that the validation print is stable over time and does
not reflect this specific behaviour. It is expected that a typical validation print is not used longer than 3 mon
...
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