ISO 12647-7:2016

INTERNATIONAL ISO
STANDARD 12647-7
Third edition
2016-11-15
Graphic technology — Process control
for the production of halftone colour
separations, proof and production
prints —
Part 7:
Proofing processes working directly
from digital data
Technologie graphique — Contrôle des processus de confection de
sélections couleurs tramées, d’épreuves et de tirages —
Partie 7: Processus d’épreuve travaillant directement à partir de
données numériques
Reference number
ISO 12647-7:2016(E)
©
ISO 2016

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ISO 12647-7:2016(E)

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ISO 12647-7:2016(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 3
4.1 Colour difference measurements . 3
4.2 Data files, simulation of screens. 3
4.2.1 Data delivery . 3
4.2.2 Screen frequency . 3
4.2.3 Screen angle . 3
4.2.4 Dot shape . 3
4.2.5 Halftone proofs screening . 3
4.3 Proof print . 3
4.3.1 General. 3
4.3.2 Proofing substrate colour and gloss . 4
4.3.3 Colouration of printed parts . 4
4.3.4 Gamut . 5
4.3.5 Permanence of proofing substrate and printed parts . 5
4.3.6 Repeatability of proof printing . 6
4.3.7 Colourant rub resistance . 6
4.3.8 Ink set gloss . 7
4.3.9 Tone value reproduction limits . 7
4.3.10 Reproduction of vignettes . 7
4.3.11 Image register and resolving power . 7
4.3.12 Margin information . 7
5 Test methods . 8
5.1 Viewing conditions . 8
5.2 Control strip . 8
5.3 Additional test objects . 9
5.3.1 Resolution . 9
5.3.2 Primary and secondary process colours . 9
5.3.3 Resolving power . 9
5.3.4 Uniformity . 9
5.4 Colour measurement . 9
5.5 Measurement of gloss .10
5.6 Visual appraisal of proof-press-print matches .10
Annex A (normative) Technical requirements for proofing conformity .11
Annex B (normative) Rub resistance of the proof colourant .15
Annex C (normative) Outer gamut patches.18
Annex D (informative) Organizational certification routines for visual appraisal of proof-
print press-print matches .21
Bibliography .23
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ISO 12647-7:2016(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 on 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 the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 130, Graphic technology.
This third edition cancels and replaces the second edition (ISO 12647-7:2013), which has been
technically revised with the following changes:
— a number of anomalies identified by industry experts have been addressed;
— substrate selection and measurement specification has been modified to reflect industry practice;
— approximately equivalent CIEDE2000 colour difference values have been added;
— basic support for spot inks has been added;
— wording has been updated to reflect current terminology and industry thinking.
A list of all parts in the ISO 12647 series can be found on the ISO website.
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ISO 12647-7:2016(E)

Introduction
ISO 12647-1 serves to provide definitions, the general principles, the general order, the material to be
covered in ISO 12647-2 to ISO 12647-8, the definition of the data, the measurement conditions, and the
reporting style.
This document relates to the subject of digital proofing and establishes proofing requirements for the
most demanding part of the printing and publishing market.
This document specifies aim values (or sets of aim values) and tolerances for the primary parameters
specified in ISO 12647-1 for digital proof printing. Primary parameters that define a printing condition
include screening parameters (where applicable), the colours of the solids, the colour of the print
substrate, colours of intermediate tint values and the tone curve. This document also specifies test
methods for those properties of digital proof prints and their substrates that are considered relevant
for stable and reliable proofing conditions, and thus for a certification procedure.
The graphic technology industry makes extensive use of proofing to predict the rendering of digital data
files by a wide variety of high-definition, high-quality off-press printing processes and applications.
Each prediction is based on a characterization data set that defines a particular printing condition.
Typically, the specified printing condition is defined through an International Color Consortium (ICC)
profile or the associated characterization data set, both of which relate source data and colorimetric
values of the printed colour. Such data may be derived from printing conditions conforming to the
pertinent process standard of the ISO 12647 series by industry trade groups or individuals.
The purpose of a proof print is to simulate the visual characteristics of the finished production print
product as closely as possible. In order to visually match a particular printing condition, proofing
processes require a set of parameters to be specified that are not necessarily identical to those put
forward in ISO 12647-1 or another part of ISO 12647. This is caused by differences in colourant spectra
or phenomena such as gloss, light scatter (within the print substrate or the colourant), and transparency.
In such cases, it is also found that spectrocolorimetry takes precedence over densitometry.
Another problem area is the matching of a double-sided production print on a lightweight printing
substrate, such as often used in heat-set web and publication gravure printing, to a digital proof on
a nearly opaque substrate. If the proof was produced using a colour management profile based on
measurements with white backing, there will be an unavoidable visual and measurable difference
between the proof on the one hand and the production print placed on black on the other hand. A
black backing is required for double-sided production printing on non-opaque prints, as specified
in the pertinent parts of ISO 12647. The possible occurrence of such differences needs to be well
communicated, in advance, to all parties concerned.
Historically, there has been no consistency in the way that either the characterization data or the
criteria and limits for a satisfactory match have been provided. This has led to significant redundancy
and inconsistencies in the evaluation of proofing systems for different, but similar, applications, and a
cost and time burden on the industry. This document therefore attempts to provide guidance in this
area by providing specifications and associated testing procedures.
Annex A summarizes the requirements for the digital proof prints listed in the main body of this
document; these are weighted with respect to their relevance in three typical situations:
— requirements with which a proof print, made for a particular printing condition, must comply if it
is to be referenced in a contract between the printer and the provider of the digital data (Certified
Proof Creation);
— requirements with which a vendor’s proofing system, comprising hardware and software, must
comply if it is to be considered capable of reliably producing digital contract proofs for a particular
printing condition (Certified Proofing System);
— requirements with which a proof print made for a particular printing condition must comply when
tested in the field using only a control wedge (Certified Field Proof).
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ISO 12647-7:2016(E)

ISO 12647-8 defines requirements for validation prints. Because data are exchanged electronically
and visualizations of those data are produced at multiple sites, there is a market need for defined
requirements for validation prints to promote a degree of consistency throughout the workflow.
Validation prints are intended to be used at early stages of the print production workflow, particularly
at the document design stage and have less stringent requirements, particularly on colour fidelity, to
allow their production on less elaborate and less costly devices than are required for contract proofs.
Validation prints are not intended to replace “contract proofs” as specified in this document for
predicting colour on production printing devices. It is expected that the modifications of the
requirements for both contract proofs and validation prints, along with the requirements for contract
proofs, will continue in the future as industry requirements and imaging technologies develop.
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INTERNATIONAL STANDARD ISO 12647-7:2016(E)
Graphic technology — Process control for the production
of halftone colour separations, proof and production
prints —
Part 7:
Proofing processes working directly from digital data
1 Scope
This document specifies requirements for systems that are used to produce hard-copy digital
proof prints intended to simulate a printing condition defined by a set of characterization data.
Recommendations are provided with regard to appropriate test methods associated with these
requirements.
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° 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 12639, Graphic technology — Prepress digital data exchange — Tag image file format for image
technology (TIFF/IT)
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 13655, Graphic technology — Spectral measurement and colorimetric computation for graphic
arts images
ISO 15397:2014, Graphic technology — Communication of graphic paper properties
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12647-1 and the following apply.
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ISO 12647-7:2016(E)

ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
chromatic primaries
cyan, magenta and yellow process inks
3.2
CIELAB chromaticness difference
ΔC
h
difference between two colours of approximately the same lightness projected onto a constant lightness
plane in the CIELAB colour space
2 2
Note 1 to entry: This is calculated as ΔCa=−()CIECIEab+−()CIECIEb .
h ) 12 12
3.3
digital proof
soft-copy proof or hard-copy proof produced directly from digital data, on a display or a substrate,
respectively
3.4
digital proof print
digital hard-copy proof
digital proof (3.3) produced as a reflection copy on a proofing substrate (3.5)
3.5
proofing substrate
printing substrate used for hard-copy proofing processes
3.6
halftone proof
proof print made using the same screening technology (generally centre-weighted halftone dots) as the
intended production printing
Note 1 to entry: This is done to attempt to produce (and therefore check for the existence of) the same screening
artefacts, such as rosettes, moiré, or aliasing patterns, as expected in the corresponding production print. One
possibility is to base proofing on the bitmap produced on the production plate or film setter.
3.7
primaries
set of process inks: cyan, magenta, yellow and black
3.8
print stabilization period
time elapsed since the production of a proof print until a stable colour is achieved
Note 1 to entry: This property is to be specified by the manufacturer.
3.9
spot colour inks
inks which are not part of the set of process inks
Note 1 to entry: Spot colour inks are often used when printing brand colours.
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ISO 12647-7:2016(E)

4 Requirements
4.1 Colour difference measurements
In previous revisions of this document, CIELAB 1976 colour difference measurements (ΔE* ) were
ab
used as detailed in ISO 13655 for normative colour difference measurements.
Conformance with this document requires the reporting of all colour differences as CIEDE2000 (ΔE ).
00
NOTE The relationship of ΔE* to ΔE varies throughout the colour space and there is no simple correlation
ab 00
between the two metrics. Users are advised that some proofs that are in conformance with ISO 12647-7:2013
may not be in conformance with this document and that some proofs that are in conformance with this document
may not be in conformance with ISO 12647-7:2013.
4.2 Data files, simulation of screens
4.2.1 Data delivery
Digital proofing systems should accept digital data delivered as PDF/X data files as defined in ISO 15930
(all parts) or TIFF/IT files as defined in ISO 12639. Where TIFF/IT files are used, colour information
shall be included using tag 34675 or tag 34029 as defined in ISO 12639.
PDF/X requires that the intended printing condition be indicated. Where the intended printing condition
is included in the registry of characterizations maintained by the International Color Consortium (ICC)
and the digital data are cyan-magenta-yellow-black (CMYK), the name used in the ICC registry is usually
used for identification in lieu of including an ICC output profile. If the intended printing condition is not
included in said registry, PDF/X requires that an ICC output profile be included. If the data are other
than CMYK, the data are required to be defined colorimetrically using an ICC input profile or another
mechanism and an ICC CMYK output profile is required to be included; the rendering intent to be used
with the output profile is required to be communicated.
4.2.2 Screen frequency
Halftone proofs should have the same screen frequencies (screen rulings) as the production press print
to be simulated within a tolerance of ±3/cm.
4.2.3 Screen angle
Halftone proofs should have the same screen angles (with a tolerance of ±3°) as the production print to
be simulated.
4.2.4 Dot shape
Halftone proofs should have the same general dot shape as the production print to be simulated.
4.2.5 Halftone proofs screening
Where halftone proofs are used and the screen frequency, screen angle or dot shape are different from
that of the production press to be simulated, these differences shall be reported.
4.3 Proof print
4.3.1 General
When evaluating and communicating proofing substrate properties, the list of required criteria for
communication described in ISO 15397 should be followed.
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ISO 12647-7:2016(E)

4.3.2 Proofing substrate colour and gloss
In an ideal situation, the digital proofing substrate should be the same as the substrate to be used for
production printing. As this ideal situation is seldom possible, the digital proofing substrate shall fulfil
all of the following criteria.
a) The gloss level of both the printing substrate and proofing substrates shall be estimated as one of
matte, semi-matte or glossy either by the substrate manufacturer or by measuring as described in
5.5. Matte proofing substrates shall not be used to make proofs for glossy printing substrates and
glossy proofing substrates shall not be used to make proofs for matte printing substrates.
b) The white point of the unprinted proofing 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 proofing substrate should have a CIEL* value that is higher than the
substrate of the printing condition to be simulated.
c) The proofing substrate should belong to the same fluorescence classification as the production
paper. Fluorescence classification in four levels of faint, low, moderate, and high shall be made
using the testing procedures described in ISO 15397:2014, 5.12.
NOTE Fluorescence as defined in ISO 15397 is calculated by measuring D65 brightness evaluated as per
ISO 2470-2 with UV included (UV) and UV excluded (UV ) and taking the ratio UV/UV (see ISO 15397 for
ex ex
details). Usual categories for fluorescence are faint, low, moderate and high. In practice, it is often useful to add
an OBA free category in which case the faint category is split into OBA free and faint. The categories and ranges
for each are shown in Table 1.
Table 1 — Fluorescence categories and ranges
Category name Range
OBA free 0 ≤ OBA free ≤ 1
Faint 1 < faint ≤ 4
Low 4 < low ≤ 8
Moderate 8 < moderate ≤ 14
High 14 < high ≤ 25
4.3.3 Colouration of printed parts
The measurement conditions shall be as specified in 5.4; the digital control strip specified in 5.2 and an
ISO 12642-2 compliant chart shall be used.
The CIELAB colour coordinates of the process colour solids shall agree with the pertinent aim values
of the printing condition to be simulated as given by the data (see 4.2.1), within 3,0 ΔE units. The
00
CIELAB metric hue difference for CMY shall not exceed 2,5.
The variability of the colouration across the proof print format is limited by the provision that the
colours of nine measurement locations evenly spaced on the test objects (see 5.3.4), which have been
printed without prior modification in view of the printing condition, shall have the following:
— a standard deviation of less than 0,5 each for values of L*, a*, and b*;
— a maximum of 2,0 ΔE units between the average value and any one point.
00
The CIELAB colour coordinates of the control patches, defined in 5.2 or ISO 12642-2, shall agree with
the pertinent aim values of the printing condition to be simulated as given by the data (see 4.2.1) within
the tolerances specified in Table 2.
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ISO 12647-7:2016(E)

If the proofing conditions are such that the simulation of the production printing substrate requires
overprinting of the proofing substrate, the maximum colour difference between the overprinted
proofing substrate and the production printing substrate shall be less than or equal to 3,0 ΔE units.
00
Table 2 — Additional tolerances for control patches
Control patch description Tolerance
All patches specified in 5.2 except spot colour ink patches Maximum ΔE ≤ 5,0
00
Average ΔE ≤ 2,5
00
A CMY overprint scale roughly replicating the neutral scale for an average
Maximum ΔC ≤ 3,5
h
printing condition comprising a minimum of five patches spaced
Average ΔC ≤ 2,0
h
approximately uniform intervals across the tone scale
All patches of ISO 12642-2 Average ΔE ≤ 2,5
00
95th percentile ΔE ≤ 5,0
00
All spot colour ink solid patches specified in 5.2 Maximum ΔE ≤ 2,5
00
NOTE 1  The tolerances pertain to the deviation of the proof values from the values of the characterization data of the
printing condition to be simulated.
The specification of ΔE tolerances lower than 2,5 is presently not practical due to poor inter-model agreement; however,
00
when the same instrument is being used to make both sets of measurements, it is recommended that the tolerances be halved.
If the final proof print is subjected to surface finishing, the final colours might deviate significantly from those of the
unfinished print. In this case, a new proofer or simulation profile or other adjustments are required.
Spot colour ink solid patches should be clearly identified by the CIELAB colour of the solid spot ink on the print substrate.
There is no standard way to communicate the intended colour of a tint of a spot ink and so communication of spot ink tint
aim values and tolerances shall be determined by a separate agreement between participants, for example by means of a
physical reference sample.
NOTE 2  Previous versions of this document used the metric ΔH which is very unstable for differences close to the neutral
axis and so this has been replaced by chromaticness difference ΔC which provides a more reliable measure.
h
4.3.4
...