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INCQC 2012 Tutorial Verona en 111201

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23.11.2011 23.11.2011 1 © 2011 WAN-IFRA Roland Thees INCQC 2012–2014 Verona, 1. December 2011 Roland Thees, Industrial Engineer Project Manager Consulting WAN-IFRA GmbH & Co. KG ISO Committee Member [email protected] © 2011 WAN-IFRA Roland Thees, Page 2 INCQC 2012-2014 International Newspaper Color Quality Club Organized by IFRA since 1994 Confirms a newspaper‘s high standard of printing quality Helps the newspaper to convince advertisers and agencies of its productivity Supports all efforts of a newspaper to generate customer loyalty by ensuring satisfied and convinced readers
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23.11.201123.11.2011

11

© 2011 WAN-IFRA Roland Thees

INCQC 2012–2014

Verona, 1. December 2011

Roland Thees, Industrial EngineerProject Manager ConsultingWAN-IFRA GmbH & Co. KGISO Committee [email protected]

© 2011 WAN-IFRA Roland Thees, Page 2

INCQC 2012-2014

International Newspaper Color Quality Club

Organized by IFRA since 1994

Confirms a newspaper‘s high standard of printing quality

Helps the newspaper to convince advertisers and agencies of its productivity

Supports all efforts of a newspaper to generate customer loyalty by ensuring satisfied and convinced readers

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© 2011 WAN-IFRA Roland Thees, Page 3

Topics of the INCQC Tutorial

Objective of the competition

Benefits of participation and Club membership

Time schedule and deadline overview

Printing in accordance with the ISO 12647-3 newspaper standard

Innovations in the standard expected for 2012

INCQC 2012-2014 requirements, instructions and categories

Continuous quality control – Self-Check, IFRA Check

Criteria and judging the general printing quality

Tools and ways to achieve high-quality newspaper printing

© 2011 WAN-IFRA Roland Thees, Page 4

Agenda 1. December 2011

Introduction of Trainer and of Participants

Importance, use and objective of the INCQC

Goals and benefits of standardization

Specifications of the Coldset 12647-3 standard

Modifications to be expected in the standard in 2012

INCQC procedure, time, schedule and administration

Instructions, technical details and General Print Quality evaluation

Quality Management

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© 2011 WAN-IFRA Roland Thees, Page 5

Worldwide support (as of November 2011)

Associazione Stampatori Italiana Giornali (ediland.it)

Asociación Técnica de Diarios Latinoamericanos (atdl.org)

BasICColor (BasICColor.de)

EAE (eae.com)

Goss International (gossinternational.com)

manroland AG (manroland.com)

Newspaper Association of America (naa.org)

Q.I. Press Controls BV (www.qipc.com)

Sanomalehtien Litto (sanomalehdet.fi)

X-Rite (xrite.com)

Zeitungs Marketing Gesellschaft (zmg.de)

© 2011 WAN-IFRA Roland Thees, Page 6

Objective of the INCQC

To support the newspaper in relation to customer loyalty (only asatisfied generates satisfied advertisers)

To ensure consistently high-quality daily newspaper production

To drive the trend towards full-color, attractive newspaper pages

To provide marketing materials so that the newspaper can present itself convincingly to agencies as a competent advertising partner

To promote the ISO quality standards worldwide in order to ensure a uniform appearance of printed color ads

To offer attractive IFRA Club membership in order to promote the sharing of experience

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© 2011 WAN-IFRA Roland Thees, Page 7

Benefits of INCQC participation

Ensures competitiveness towards rival media

Provides promotional material to help attract advertisers

Winners are highly respected and honoured with a prestigious award

Workflow is optimized and know-how and competence is gained for the selection of materials and production methods

Better control of progress in standardisation based on known parameters

Provides a basis for discussions and facts for negotiations with suppliers

Motivates personnel and honours efforts

Customer complaints can be recognised or rejected objectively based on technical measurements (printing within or outside of ISO)

© 2011 WAN-IFRA Roland Thees, Page 8

Reasons for INCQC participation

Result of a survey in January 2011, INCQC + Certification

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© 2011 WAN-IFRA Roland Thees, Page 9

Registration

Online registration,brochure and instructionsunder:

www.colorqualityclub.org

Registration

Continuous quality check:

www.colorqualityclub.org

Run Self Check

© 2011 WAN-IFRA Roland Thees, Page 10

Time frame

Instructions available for downloading from 29.06.2011

Registrations received up to 17.10.2011 are offered a free test run inNovember 2011. The report shows how much optimization work remains to be done.

Mailing of a measured reference print in October 2011

Registration deadline for participation is 31.12.2011

Test chart production from January to March 2012 = 1 x monthly

Submission of test prints by end of the month in each case

Production of the monthly evaluation by 15th of the following month

The overall evaluation per category, incl. ranking, ready by June 2012

INCQC awards presentation ceremony during IFRA Expo 2012 in Madrid

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© 2011 WAN-IFRA Roland Thees, Page 11

INCQC 2012 Time Schedule

Downloads and test runs

© 2011 WAN-IFRA Roland Thees, Page 12

Conditions of participation

A participant is always a specific newspaper title at a specific location

Every publishing house and every printing operation can register an unlimited number of titles

A publishing house can register several locations eith the same title, thus permitting a comparison of locations

Participation is treated with strict confidence

Club membership and the certificate are issued for a newspaper title produced at a specific printing location on condition that the minimum number of points stated in the instructions were obtained

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© 2011 WAN-IFRA Roland Thees, Page 13

Features of INCQC 2012-2014

Test chart production within the framework of the regular newspaper production times, without resource-consuming special shifts

Creation of participant categories in order to cover all processes involved in newspaper production

Evaluation of the “daily quality” instead of special production runs

Establishment of the capacity of an operation to consistently satisfy a defined quality level

Avoidance to a large degree of a subjective jury

No limitation on the number of Club members

© 2011 WAN-IFRA Roland Thees, Page 14

ISO 12647

Graphic technology standard that defines process control for production of color separation, proof and production print

7 sub divisions

-1: Measurement methods

-2: Offset lithography

-3: Coldset offset (Newspaper production)

-4: Publication gravure printing

-5: Screen printing

-6: Flexographic printing

-7: Proofing

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© 2011 WAN-IFRA Roland Thees, Page 15

ISO for the news publishing industry:

Graphic technology standard 12647-3:2005

12647 is a set of standards consisting of several subversions. -3 is newspaper printing, -2 is the general offset standard, -1 describes the measuring processes

:2005 means that this version was published in 2005. As the “youngest” version, it continues to be valid

ISO standards are subject to review at 5-year intervals

The newspaper printing standard was published for the first time in 1998

17 pages worth reading

© 2011 WAN-IFRA Roland Thees, Page 16

Why standardisation?

Different quality of raw materials

Materials from many different suppliers

Different newsprints in same production run

Batch to batch variations

Usual problems – Wrong shades of ink, darker newsprint shade, set-off and print through affecting the general print quality, fluff accumulation, runnability issues etc…

Unless raw materials are standardised, production cannot be standardised

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© 2011 WAN-IFRA Roland Thees, Page 17

Advantages of applying the standard

An outstanding characteristic of newspapers is their capacity, despite independent production sites, to achieve uniform colour reproductionworldwide by the use of the ISO standard

Deviations can be avoided by knownquality parameters

Irregularities in the used materials are recognisable and can be eliminated

Globally operating advertising agencies and companies expect the exact repro-duction of the intended colour tone

© 2011 WAN-IFRA Roland Thees, Page 18

Aim of a standardized newspaper production

Plannable, predictable results for the graphic designer

Consistently high-quality printing in daily production

Personnel management:

Increasing quality consciousness and acquiring know-how

Personnel motivation by concrete targets

Saving costs by analysis of weak points

Customer loyalty:

Promotionally effective certificate gives competitive edge

High-quality product appearance flatters the reader

Qualtifiable production quality generates advertiser loyalty

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© 2011 WAN-IFRA Roland Thees, Page 19

Standards prevent prints in different visual appearance

© 2011 WAN-IFRA Roland Thees, Page 20

Advertisers problem with Newspapers

Identical Artwork as PDF File sent to multiple Printers

Printed at many different printing sites

Any print locations with specific settings

Lot’s of different Hardware (e.g. presses) and software

Different configurations within the presses

Country-specific materials like ink and paper

=> Same Ad may reproduce differently with unstandardised production process

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© 2011 WAN-IFRA Roland Thees, Page 21

Core topics of the ISO 12647-3 standard

Tone value increase curve uniformly defined with 26% in the mid-tone

Tone value increasewithin 5% tolerance (+/-) of the tone value increase curve

Mid-tone spread between max. 6%

40er chain-dot screen

240% coverage

© 2011 WAN-IFRA Roland Thees, Page 22

Newsshade for ISO standard paper

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© 2011 WAN-IFRA Roland Thees, Page 23

ISO color values and register precision

The shown ISO color values apply for coldseton standard newsprint

The register deviation should fall short of 0.3mm and be less than0.15 mm

© 2011 WAN-IFRA Roland Thees, Page 24

ISO color space for coldset

The recommended color sequence is either

CMYK

or KCMY

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© 2011 WAN-IFRA Roland Thees, Page 25

ISO AM screen angle definition

The screen angle of the dominant color should be 135°

© 2011 WAN-IFRA Roland Thees, Page 26

Solid Ink Densities

For information only

To give a reference for printer to help in printing

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© 2011 WAN-IFRA Roland Thees, Page 27

Needs why to modify the 12647-3 standard

Technical reasons: Technological advances are changing both operational equipment as well as working methods

Emotional reasons: Personnel, readers and advertisers are changing their behaviour, the attitude towards the medium“newspaper” has changed

Competition: There is a large number of competing media(iPad, tablet, online), the decision to buy a product depends not only on the content but also on the overall appearance

Change of the existing static production parameters to defining minimum levels

© 2011 WAN-IFRA Roland Thees, Page 28

ISO 12647-3:2005 Reasons for change

Analog data handling is dying out:Films practically no longer usedPlate exposure systems practically no longer used

All definitions for “Film” can be removed (this involves several pages) in order to permit concentration on the printing forme

Changes to proofing -> digital or softproof

Clear incorporation of “waterless offset”

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© 2011 WAN-IFRA Roland Thees, Page 29

ISO 12647-3:2010 -> Screens

Up to now, for example, 500 l/cm specified for imagers, in future 500 l/cm or more

The specification for the 40 chain-dot screen changes to a bandwidth of 40 to 54 screen, with dot link-up at 40% and at60%

Non-periodic screens, (FM, frequency-modulated), otherscreen angles and other dot shapes are permissible

It is expressly stated that, despite deviating settings, the printed final product must be ISO-conform, this concerns especially the tone value increase and color values

© 2011 WAN-IFRA Roland Thees, Page 30

ISO 12647-3:2010 -> Coverage

Technical remark: FM screens have up to ca. 6% less tone value increase than AM screens. Theoretically, this can be corrected in the RIP. However, in case of major corrections this can lead to stepped gradations and fuzziness in smooth backgrounds.

240% coverage in print is the maximum (previously 260%), 220% is given as a reasonable target

In case of a high ink laydown, the black share should be at least 90% (previously 85%)

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© 2011 WAN-IFRA Roland Thees, Page 31

ISO 12647-3:2010 -> Preflight

The need for a PreFlight Check is specified for the first time

Reason: no uniform standard exists for data production

Software:InDesign, CS1 bis CS5Quark, V3.3 bis V8Corel, V9 bis Suite X5Pagemaker, V5 bis V7MS Publisher 2007/2010Scribus, V1 bis 1.3Illustrator, V7 bis CS5Freehand, V7 bis V11Inkscape, V 0.47Photoshop, V5 bis CS5Gimp, V1 bis 2.7Word, Power Point etc.

Betriebssysteme:MAC OS X ffMac OS bis 9.2Windows XP, WIN 7Linux, UNIXAndroid, Chrome OS,Web-OS von HP

Fonts:TrueTypeType 1OpentypeType 3CID-FontsBitMap Fonts

Kompression: ZIP, GIF, TIFFJPEG, JPEG 2000JBIG2, LZW, CCITT

Bilder1 Bit2 Bit, 4 Bit8 Bit12 Bit, 16 Bit

PDF-Formate:PDF 1.2 PDF 1.3; JPEG, Device NPDF 1.4; Transparenzen PDF 1.5; LayerPDF 1.6; Opentype FontsPDF 1.7; multiple filesPDF 1.8EPS: Level 1,2,3PS: Level 1,2,3DCS: 1 und 2

© 2011 WAN-IFRA Roland Thees, Page 32

ISO 12647-3:2010 -> New: Gray balance

Calculation of the visual values of neutral gray

Depending on paper white and maximal CMY application

a* = a*paper x (1 - 0.85 x (L*paper - L*) / (L*paper – L*cmy))

b* = b*paper x (1 - 0.85 x (L*paper - L*) / (L*paper – L*cmy))

The 0.85 multiplication factor describes the visual perception of85% of the actual paper white (put another way: 85% of the light is reflected, 15% absorbed)

Identical formula as in the offset standard 12647-2

Standard values can be published only for defined printing conditions and the accompanying ICC profile

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© 2011 WAN-IFRA Roland Thees, Page 33

ISO 12647-3:2010 -> Printing condition

First-time definition of a printing condition for standard newsprint, with the objective of extending this Table in the future by additional conditions, e.g. SC or LWC paper

© 2011 WAN-IFRA Roland Thees, Page 34

ISO 12647-3:2010 -> Newsshade

Overview of the target values for newsprint

Unchangedtolerance values:

ΔL*: 4

Δa*: 2

Δb*: 2

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© 2011 WAN-IFRA Roland Thees, Page 35

ISO 12647-3:2010 -> L*a*b* Target values

Separate listing of the target values on black and white backing in order to avoid mix-ups

Minor adaptation of the magenta b* value to “-1” (old: “-2”), based on more than15,000 WAN-IFRAmeasurements

© 2011 WAN-IFRA Roland Thees, Page 36

ISO 12647-3:2010 -> Color tolerances

Definition of color tolerances both for the primary as well as binding for the secondary colors (previously only informative)

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ISO 12647-3:2010 -> Color register

Register deviation must be ≤ 0.2 mm

The color register deviation is calculated by the theory ofPythagoras:

a² + b² = c²

Cyan (ref) Magenta Yellow BlackLateral register (in micrometres) 0 50 10 -50,00Circumferential register (in micrometres) 0 0 10 -143,62

175,00M-K

Largest deviation between two colors in register Largest deviation between:

-150

-100

-50

0

50

-100 -50 0 50 100

MagentaYellowBlackCyan (ref)

© 2011 WAN-IFRA Roland Thees, Page 38

ISO 12647-3:2010 -> TVI curve

Uniform 26% curve

Calculation of the tone value-specific increase by the polynomial function

TVI (x) = 100*(a*x4 + b*x3 + c*x2 + d*x)

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© 2011 WAN-IFRA Roland Thees, Page 39

ISO 12647-3:2010 -> Mid-tone spread

Simplification of the existing Table in order to facilitate understanding and specification of the measuring patches as40/50 and 70/80

The mid-tone spread applies for all CMYK colors and is no longer confined to CMY as before

© 2011 WAN-IFRA Roland Thees, Page 40

ISO 12647-3:2010 -> Densities

Densities serve only for information purposes, are not part of the standard and are based on empirical values

ISO Status E, relative density (calibration on the paper), with polarizing filter:

Cyan/Magenta/Yellow D 0,90

BlackD 1,10

ISO Status T, absolute density, without polarizing filter:

Cyan D 0.90; Magenta D 0.90; Yellow D 0.85; Black D 1.05

Paper values C: 0,23, M: 0,24, Y: 0,27, K: 0,22

N.B.: Status T and Status E values are not comparable, there are major deviations especially in yellow

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© 2011 WAN-IFRA Roland Thees, Page 41

INCQC 2012-2014

Categories and test charts

Instructions and technical details

© 2011 WAN-IFRA Roland Thees, Page 42

ISO 12647-3:2010 -> INCQC 2012-2014

The rules of the previous INCQC already integrated in part the planned innovations in the newspaper printing standard

Gray balance, but with existing values

Mid-tone spread CMYK

Other new features of INCQC 2012-2014

Evaluation of the CMYK colors corresponding to the Delta E deviation in accordance with the ISO specification

Evaluation of tone value increase at 40% (as to date) andadditionally in the 70% measuring patch

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© 2011 WAN-IFRA Roland Thees, Page 43

INCQC participation categories

4 categories allow the participation of nearly all newspaper titles,independent of the production process used. The evaluation criteria differ accordingly

Category 1: Coldset-offset on newsprint

Category 2: Heatset or UV offset on newsprint

Category 3: Heatset or UV offset on SC or LWC paper

Category 4: Extra category for newspaper printing on tinted paper or for printing processes outside of offset printing, e.g. flexo or digital printing

The category assignment is done online up to the time the test begins

© 2011 WAN-IFRA Roland Thees, Page 44

Cuboid version for 2012

46% of the participants in a survey preferred the Cuboid with 6x4 dots, as it is easiest to position this in the regular production run with the approval of the newsroom

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© 2011 WAN-IFRA Roland Thees, Page 45

Development of the IFRA Cuboid

The Cuboid was designed at WAN-IFRA in close cooperation with international color experts

Since 2009, the Cuboid has become established worldwide at newspapers as an accepted print test element

the Cuboid can run in regular production

its handling corresponds to that of a customer ad

the consistent high quality is measured and judged under regularconditions

time and cost-intensive special production runs with exceptional investment of resources are avoided

© 2011 WAN-IFRA Roland Thees, Page 46

INCQC test chart “IFRA Cuboid 2012”

Single-column colorfiller ad, 42 x 28 mm

With integrated color register measuring element

Scaling must be avoided under all circumstance

Version ID for each test month

Chaning version ID

Color register measuring element

Corner dots for measuring head positioning

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© 2011 WAN-IFRA Roland Thees, Page 47

Color values of the IFRA Cuboid 2012

Positioning possible in both horizontal and upright format

Scaling must be avoided under all circumstances

© 2011 WAN-IFRA Roland Thees, Page 48

Positioning of the Cuboid

Anywhere in the main section as a filler ad, printed in the entire run or by means of a plate change after the regular production run

No positioning in the fold, as that complicated the evaluation

A different version of the Cuboid for each test month (January to March 2012) is made available for downloading

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© 2011 WAN-IFRA Roland Thees, Page 49

Cuboid 2012 handling - Rules

Position like a customer ad, without additional ink trapping elements, etc.

Do not change format

Do not position in the fold, as otherwise the evaluation of the printed sample is adversely affected by set-off and soiling

The reverse side of the Cuboid must be printed with newspaper-type contents

Newspaper pages that only contain the Cuboid, have nothing printed on the reverse side, are printed on deviating paper grades or have different/missing pin holes on the page are evaluated as a special print with individual points subtraction

© 2011 WAN-IFRA Roland Thees, Page 50

Application of the ISO standard

Newspapers are usually produced on web offset presses, but delivered untrimmed

It is only by using control elements that it is possible to verify that technical criteria for production control, quality control and discerning customers have been satisfied

Traditional control strips at the head and foot of the page: good from the technical point of view, in most cases rejected by the newsroom

Ad-like test elements are widely accepted

Printing test pages outside of production

Image content-based systems

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Measuring instruments at WAN-IFRA

Spectrophotometer X-Rite EyeOne iO(measuring table)

angle of observation 2°

light source D50

measuring geometry 45°/0°

black backing

Color register measurement withTechkon RMS 910

© 2011 WAN-IFRA Roland Thees, Page 52

INCQC Instructions

Explanation of the INCQC 2012-2014 criteria

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© 2011 WAN-IFRA Roland Thees, Page 53

Cuboid color target values in category 1(coldset on standard paper)

© 2011 WAN-IFRA Roland Thees, Page 54

Cuboid color target values in category 2(heatset/UV on standard paper)

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Cuboid color target values in category 3(heatset/UV on SC or LWC paper)

© 2011 WAN-IFRA Roland Thees, Page 56

ISO tone value increase (TVI)

Category 1

26% curve

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© 2011 WAN-IFRA Roland Thees, Page 57

Newsshade

The ISO-conform lightness of newsprint (newsshade) permits a good contrast and is therefore more reader-friendly. The color cast of the paper should be low. A sufficient opacity minimizes the show-through that is unavoidalbe in newsprint

Evaluation: The target values less the ISO tolerances conttitute the minimum level in each caseje. A lighter paper than specified by ISO is rewarded by allocation of the full number of points

© 2011 WAN-IFRA Roland Thees, Page 58

Newsshade tolerances

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Mid-tone spread

The mid-tone spread is one of the decisive quality factors for the color effect of a newspaper. In particular the widespread trend towards ink-saving methods via ICC profiles or independent “InkSaver” software is transforming the former skeleton black in the color image into a dominant factor. Due to this major significance, all inks in this evaluation are subject to the narrow ISO tolerances of mid-tone spread for colors.

© 2011 WAN-IFRA Roland Thees, Page 60

Mid-tone spread

Report presentation

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Tone value increase

It is only by observing the dot gain specified in the ISO criteria that it is possible to clearly plan and verify the expected printed color result throughout the production chain, from draft to proof, preview and final printing. This is the only wayfor the graphic designer and customer to reliably predict the effect of the color in a printed ad. The following figures are valid only for category 1

© 2011 WAN-IFRA Roland Thees, Page 62

Tone value increase

The graphic is based on the bases of 40% and 70%

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© 2011 WAN-IFRA Roland Thees, Page 63

Gray balance

The gray balance allows neutral, pinting free of color casts. Early detection of color shifts and a “ fine tuning”of the page

The light paper gray is the individual, neutral color reference adapted for the eye.

Because of the paper color, the gray axis is usually at an angle to the L* axis

Paper color

Light gray, within the tolerance

Medium gray, outside the tolerance

Dark gray, within the tolerance

Darkest CMY gray

© 2011 WAN-IFRA Roland Thees, Page 64

Calculating the gray balance

(1) Calculation of the individual reference gray axis based on newsshade and dark CMY gray

(2) Mathematical definition of the ideal a*b* values of the printed CMY light gray, medium gray and dark gray based on the L* value in each case

(3) The measured a*b* values are compared to the individually calculated, ideal a*b* gray values

The calculated color difference is “Delta C* absolute”

The max. permissible deviation “Delta C* absolute” is 3

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Evaluation of the gray balance

The printed CMY gray tones are compared to the reference gray axis. The deviation is given as “Delta C* absolute”

© 2011 WAN-IFRA Roland Thees, Page 66

Graphic representation of gray balance

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Color space

In the three-dimensionalcolor space we calculate the color volume corresponding to the selected category in order to obtain a useful comparative value

© 2011 WAN-IFRA Roland Thees, Page 68

Color conformity of the individual colors

Included in the standard is a definition for both primary and secondary colors in each case a target value, described as color gamut and defined by L*a*b* values

The supplied colors must match these values in order to enable the printing plant to satisfy the required color standards in the printed product

Only minor adjustments can be made by means of density variations during the printing process permit

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Calculating color conformity

The objective is to establish whether the color used achieves the minimum range

If the color and print production exceed what the concerned standard demands, this theoretically constitutes a deviation butthe full number of points are still awarded for this good result

The measured color is compared to the Chroma (C*ab) of the reference color. If the measured value C*ab larger than or equal to the C*ab reference and the minimum lightness L* and color angle Hue (h*) angle are satisfied, then the achieved color gamut is larger and therefore better than the ISO standard

If the color gamut within or less than the standard, an evaluation is done corresponding to the Delta E calculation

© 2011 WAN-IFRA Roland Thees, Page 70

Example for color conformity

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Color register

The IFRA Cuboid contains the required measuring dots, with exactly defined intervals

For the evaluation, we take the average of 3 measurements

The register deviation should be less than 0.15 mm to obtain the full number of points

© 2011 WAN-IFRA Roland Thees, Page 72

Color register

Calculation of the color register deviation is done based on the theory of Pythagoras:

a² + b² = c²

Cyan (ref) Magenta Yellow BlackLateral register (in micrometres) 0 50 10 -50,00Circumferential register (in micrometres) 0 0 10 -143,62

175,00M-K

Largest deviation between two colors in register Largest deviation between:

-150

-100

-50

0

50

-100 -50 0 50 100

MagentaYellowBlackCyan (ref)

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General printing quality

Evaluation of two production copies from 2 different months

Selected randomly from the submitted 3 x 10 copies

Evaluation of the first 16 color pages of the newspaper

Format-independent, broadsheet or tabloid

Evaluation of the general printing is done based on criteria that every user can recognise (= user principle)

© 2011 WAN-IFRA Roland Thees, Page 74

General printing quality

The marked-up copies and list of points are part of the evaluation report

The first 16 full color pages of each newspaper title start out as100% correct production

Points are subtracted for detected shortcomings/defects

= subtractive evaluation

A weighted subtraction of points is done for each recognised criterion (e.g. printing plate edges)

Independent of the intensity of the fault, points are subtractedonly 1x for the page concerned

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© 2011 WAN-IFRA Roland Thees, Page 75

Criteria “General Printing Quality”:

Color content of the newspaper

Print process quality

Color register

Mechanical printing quality

Image and graphic quality

© 2011 WAN-IFRA Roland Thees, Page 76

General Printing Quality:“Color content of the pages”

Full number of points awarded only in case of 4-color production throughout the newspaper

Points subtracted for 2c

Points subtracted for b/w pages

Reason: The error potential in 4c printing is much greater than in 2c or b/w printing

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General Printing quality:“Print process quality and color register”

Blanks in the print-out

Overinking, underinking

Density fluctuations

Show-through

Ink rub-off on hands and clothes

Mis-register

© 2011 WAN-IFRA Roland Thees, Page 78

Mechanical printing quality:

Set-off or smearing

Impressions of draw rollers, rings, marks

Hickies, picking, creasing

Ghosting, doubling

Printing plate scratches and plate edges

Pin holes pulled -out or pin holes in image area

Dirt stains, poor lateral register

Poor ribbon register

Toning, fuzziness

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Image and graphic quality

Ink piling in the image, image areas fill-in

Color cast, color saturation inconsistent

Poor screen quality (e.g. moiré)

Poor contrast range

Image too bright or too dark

Streaking, tonal value jumps

Fuzzy images (not evaluated)

Poor detail reproduction

© 2011 WAN-IFRA Roland Thees, Page 80

Evaluation of GPQ (GeneralPrint Quality:

Each criterion is applied only 1 x per page

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Percentage breakdown of the evaluation criteria

Newsshade9%

Mid-tone spread3%

Gray balance9%

Dot gain 40%3%

Color register9%

Dot gain 70%3%

Gen. Print quality46%

Color space4%

Color conformity Delta E14%

© 2011 WAN-IFRA Roland Thees, Page 82

Consistently high-quality printing

The special aspect of the INCQC is that what must be achieved is not a one-time good result with a special production run, but that the regular daily production must demonstrably show a consistent and quantifiable high quality

One of the categories (#4) is judged especially on whether it is capable of repeatably producing consistent and predictable results

For advertisers, this has the major benefit that the expected printed results are plannable and usually do not require a specal check

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Success-table

For each test run a minimum number of points for the sum total of all criteria must be achieved

The consistency check ensures that each individual criterion satisfies the standard during the test period

The evaluation reports (January to March) are produced by the middle of the month in each case

The final report for March with confirmation of Club membership is produced by June 2012

The evaluation of general printing quality is done based on 2 randomly selected copies from different months and from the reader‘s point of view

© 2011 WAN-IFRA Roland Thees, Page 84

Evaluation diagram

All criteria in the Table must be satis-fied in both horizontal and vertical direction

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Evaluation procedure

In every competition month from January to March 2012 the IFRA Cuboid must be printed at least once under standardized conditions as part of a regular issue of your newspaper.

The appropriate version of the IFRA Cuboid, duly indicated by name, must be printed for each competition month.

The IFRA Cuboid version specified for each month must be printed. Failure to observe this rule will result in the participant concerned forfeiting points.

Ten sample copies of each issue must be submitted on schedule for evaluation.

© 2011 WAN-IFRA Roland Thees, Page 86

Preparations for a successful participation

Download IFRA test element “Cuboid 2012”

Webseite „www.colorqualityclub.org“

Download, read and understand instructions

In case of queries: phone or e-mail us

Test-print the ad-like “IFRA Cuboid”

Register by 17.10. and benefit from the possibility of a free evaluation by WAN-IFRA

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Color Quality – Self Check

www.colorqualityclub.org

Color Quality Self Check is free WAN-IFRA tool with color space calculator

Online input on the WAN-IFRA website of values measured by the participant using a spectrophotometer

The Techkon RMS is required for the color register measurement

The report is sent out via e-Mail and is available for downloading

The results are meaningful only if measuring was done in accordance with the ISO and the measuring instrument used is calibrated

© 2011 WAN-IFRA Roland Thees, Page 88

Color Quality – IFRA Check

www.colorqualityclub.org

Color Quality IFRA Check is a pay-for tool with color space calculator and contains the identical measurement-based evaluation routines as the INCQC

You submit the test prints to WAN-IFRA where evaluation is done in the laboratory under standardised conditions using calibrated measuring instruments

The instruments used are the X-Rite Eyeone iO spectrophotometer for color and density measurement and Techkon RMS 910 for register measurement

The final report is sent out by e-Mail

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Steps to success

1. Use suitable paper and checked inks

2. Ensure achievement of the required color values (color gamut taking into account density values)

3. Correct the tone value increase curves via the RIP

4. Maintain color register in print production

5. Set the general printing quality at a high level:

by training and motivating personnel

by technical maintenance of the production equipment

by a willingness to allow proposals, changes and optimizations

© 2011 WAN-IFRA Roland Thees, Page 90

Where to start?

Reproduction PrePress Press

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Where to start?

Reproduction PrePress Press

© 2011 WAN-IFRA Roland Thees, Page 92

Where to start?

Reproduction PrePress Press

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Where to start?

Reproduction PrePress Press

© 2011 WAN-IFRA Roland Thees, Page 94

Take care which PDF version you use

PDF 1.2: first wide spread version, big file size

PDF 1.3: optimized for the printing industry, includes JPEG, Device N Colormanagement and good compression method

PDF 1.4: feature „transparencies“, printable only after flattening

PDF 1.5: new features „Layer, JPEG 2000, 16 Bit Images“, required conversion to run the files on the RIP

PDF 1.6: new features „Opentype fonts and N-Channel“

PDF 1.7 (ISO 32000-1): feature „multiple files in one document“

PDF 1.8: Reference in preparation (www.adobe.com)

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PDF/X-Versions for the printing industry

PDF/X is a subset of settings to generate a printable file

X-1a: only CMYK and Spotcolours

X-3: CMYK and Spotcolours, but also RGB and Lab are allowed. Requires Colourmanagement

All Fonts have to be embedded

All Images without encryption and without LZW compression

Defined BleedBox, defined TrimBox

No JavaScript, no PostScript commands, no form fields

No Transparencies, no Transfercurves

© 2011 WAN-IFRA Roland Thees, Page 96

Why to go for Ink-Saving technologies

An average newspaper faces a consumption of 20.000 kg of black ink and a total of 50.000 kg of coloured ink per year per.

Calculate € 2 per kg, in this example we‘re talking about €140.000 on Ink-costs per year

The following presentation is about the possibility to eliminateapproximate 10% to 15% costs with an investment in ink saving technology

In the above mentioned example, appr. € 14.000 to € 21.000 less expenses can be achived – means saved per year

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How is Ink-Saving working

Ink-Saving is a question of colour matching

The sum of colour elements which addition results in grey will be replaced be black only

GCR – Grey Component Replacement

Grey components:

70% Cyan + 70% Magenta + 70% Yellow = Dark Grey

30% Cyan + 30% Magenta + 30% Yellow = Light Grey

So: why printing grey with expensive coloured ink

Solution: Printing grey with black ink only

© 2011 WAN-IFRA Roland Thees, Page 98

Ink-Saving results on colour separation

Cyan Magenta Yellow Black Composite

No Ink saving,

350% TAC, Ink coverage

Ink saving,

220% TAC, Ink coverage

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Ink-Saving

Example from a big printing plant:

Ink consumption for 1.2 million copies in kg, 4/4 colour

M K Total

withoutInk Saver 408,7 268,2 1859,4

withInk Saver 264,6 346,0 1597,7

difference -144,1 +77,8 261,7

% saving

Y

852,6

755,0

-97,6

C

329,9

232,1

-97,8

14,09 %

© 2011 WAN-IFRA Roland Thees, Page 100

Ink-Saving colour effects!

No visually observable effect, people watching the printed image do not see any difference.

Colorimetric values in the composite image remain unchanged.

Achromatic areas, 3 color grey areas resulting of similar contingents of Cyan, Magenta, Yellow (e.g. 30% Cyan, 30% Magenta, 30% Yellow) are converted to Black

Heavy changes in the single colour separations:

Cyan, Magenta, Yellow are reduced

Black is increased.

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InkSaving Methods

ICC-Profiles

FM (Frequence-Modulated) screening

DeviceLink standard (=static) ICCprofiles

Vendor-specific static DeviceLink profile

Real-time dynamic DeviceLinking and immediate recalculation depending on specific data analysis per single file.

© 2011 WAN-IFRA Roland Thees, Page 102

InkSaving by using ICC-profiles

Using ICC Colour management

requires investment in ICC-profiles (some are free, like IFRA ISOnewspaper26v4.icc), usage during RGB-CMYK conversion

requires manpower and know how

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InkSaving by FM (frequence modulated) screening

Embedded in the RIP

Using FM-screening or Hybrid screening technology

requires an investment in screening technology, mostly for multiple RIP‘s

Lot‘s of suppliers are on the market

without any claim on completeness: Adobe Brilliant Screen, Agfa Sublima, Kodak Staccato, Heidelberg Diamond Screening

Results vary, some user confirm Ink-savings with FM, but there are also some discussions about it. Individual testing is required – in any case.

© 2011 WAN-IFRA Roland Thees, Page 104

FM (Frequence modulated) screening

Plenty of FM rasterelements are closely arranged to each other. They absorb more light than a comparable amount of standard AM rasterelements. This results in a lower area of printing dots, which requires in the end less ink

AM

FM

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InkSaving by DeviceLink profiles

DeviceLink Profiles, depending on standard ICC which can be embedded in applications like Photoshop

specific DeviceLink profiles which connects Input CMYK channels directly with output CMYK channels, without the loop to L*a*b*

Colour Server DeviceLink technology

dedicated colour server with applied vendor specific static device link profiles

dynamic real-time device linking by analyzing the file, generating a temporary DeviceLink profile (Input-Output profile) and immediate recalculating the colour channels.

© 2011 WAN-IFRA Roland Thees, Page 106

GCR

Example color

No UCR/GCR Moderate GCR Strong GCR

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Device Linking - Preparation for specific output devices

ICC-based or dynamic server based recalculation of the values of the different colour channels

Cyan

Magenta

Yellow

Black

Cyan

Magenta

Yellow

Black

Devices for Sheet Fed printing

Devices for Newspaper

Link to

© 2011 WAN-IFRA Roland Thees, Page 108

Benefits of Ink-Saving

Between 10 and 20% less consumption (and also cost reduction) of expensive coloured Ink

Better printability of paper and stable grey balance

Reduces colour variations during the print run

Better drying because of less ink has to penetrate the paper

Less smearing on guide and draw rollers

Reduced Fountain solution, reduced Ink mist

Less shine through

Smooth process in mailroom

Less waste in total

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Workflow with Inksaving tools

Inksaving can happen on single elements in case of usage with standard applications like Photoshop

Inksaving can happen on a stand alone Colour Server, running the whole page before ripping

Inksaving can be part of the RIP in case of using ICC-profiles or FM-screening

© 2011 WAN-IFRA Roland Thees, Page 110

Reproduction

Consistent application of color management in processinginternal and external data

Regular calibration of monitor, proof-printer, scanner

Application of IFRA ISO ICC profile contains:

ISO color space

Color of standard newsprint

240% total inking

Tone increase curves with 26%

Category 2, 3, 4: Use of improved/tinted paper and/or dryer: use special ICC profiles

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RIP

Proofing

File

LAB

LAB Generate profile for proofing system

Use ISOnewspaper26v4.icc for absolute colorimetric proofing:

on newsprint (possibly simulation)

include media wedge for analysis

Use DeviceLink to avoid Lab conversion

CMYK data

RIP

© 2011 WAN-IFRA Roland Thees, Page 112

L= 0 to 100a= -128 to 127b= -128 to 127

L*a*b* colour system

CIELAB (1976)

Exact and easier for representation

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L = 50 a = 0 b = -128

L = 33 a = +48 b = -27

white, L

black

-agreen

+ared

+byellow

-bblue

3D model of the L*a*b* colour space

© 2011 WAN-IFRA Roland Thees, Page 114

Calibration charts and targets - Examples

IT8.7/2 target for scanner profiling

IT8.7/3 target for press profiling

Gmg colorchecker chart for Digital camera profiling

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Tone value increase curve

The 26% curve is based on worldwide agreement

Newspaper customers have the possibility, by means of a proof, to simulate and judge the actual appearance of the printed ad in advance

This offers international advertisers, such as Mercedes, Toyota, Dell, CocaCola, etc., the opportunity to plan the color effect

Color content can be published with a comparable standard of quality in different newspapers worldwide

This means that specific advertising messages can be communicated not only via the text, but also through images and graphics

© 2011 WAN-IFRA Roland Thees, Page 116

Tone value increase - Factors

Screen definition, AM or FM

Paper properties

Plate and imaging method (positive/negative)

Printing blanket, compressing, cylinder packing

Solid density (ink application, ink layer thickness respectively)

Printing speed, with/without drying

Humidity, climatic conditions

Ink and inking system temperature

Fountain agent: pH, conductivity, hardness, temperature

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Mid-tone spread

Describes the difference in tone value increase between the process colors in the mid-tone (40%)

Correction in the RIP only after stabilisation of the printing process

The smaller the better are grey balance and color reproduction

Good result - consistent Negative – inconsistent and too high

© 2011 WAN-IFRA Roland Thees, Page 118

RIP settings to control the TVI

Imaging resolution 1270 dpi

Screening resolution 40 l/cm

Dot shape chain-type dot (Elliptical P)

Screen angle measured on paper

yellow 0° horizontal (3 o‘clock)

cyan 15° anti-clockwise

magenta 75° anti-clockwise

black (K) 135° anti-clockwise

Harlequin RIP: (bear in mind: 0° at 12 o’clock)

Harlequin: Extra Grey Levels ON Value = 1024

Harlequin: Precision Screening ON

Harlequin: Clear Centred Rosette OFF

Harlequin: Override Applications ON

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Controlled reproduction and print process:

Reproduction settings

Controlled platemaking

RIP settings

Generation of tonal value increase curves (TVI)

Mid-tone spread and grey balance

Measuring and optimising colour space

Measuring and improving colour register

Optimising density settings

© 2011 WAN-IFRA Roland Thees, Page 120

Plate exposure

1. Laser intensity (continuous tone wedge)

2. Check development (Thermostrip)

3. Exposure quality (CtP Testform)

4. Linearisation (RIP)

5. Continuous control

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Laser intensity control Example: AGFA N91 and UGRA/FOGRA control wedge

Problem: dot loss in print

AGFA: with full through-hardening, promised up to 400,000impressions (in practive average is 250,000)

Step 3 covered in UGRA continuous tone wedge (N91V: step 2)

No difference between step 2 and 3

(or N91V step 1 and 2 respectively)

To date, the continuous tone wedge offers the best possibility to test the correct through-hardening

© 2011 WAN-IFRA Roland Thees, Page 122

Continuous tone wedge to control Laser intensity

e.g. UGRA/FOGRA 1982, Fuji, Stouffer, …

Pay attention to differences in continuous tone steps

To be used with photopolymer and silver plates

Check if plate batch or chemistry were changed

The continuous tone wedge is the only test element that provides information about hardening

Imager should offer test mode

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Photopolymer plates

Photopolymers are negatively exposed: exposed areas are hardened with laser light and pre-heat

Laser intensity, plate sensitiveness, and plate development determine the number of possible impressions

High laser energy = high mileage (hopefully)

Excessive laser energy:

Gradation loss (tone value increase)

Line elements and type become thicker

© 2011 WAN-IFRA Roland Thees, Page 124

Developing machine

The following must be checked and documented:

Pre-heat, e.g. more than 110° C

pH-value

Pre-wash, fresh water supply, e.g. 750 ml/m2

Developer temperature, e.g. 24° C ± 2° C

Brush speed 130 rpm ± 20 rpm

Gumming 225 mg/m2 ± 50 mg/m2

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Developing machine

Frequent adjustment of brushes

© 2011 WAN-IFRA Roland Thees, Page 126

Exposure quality

Control tools:

Testforms:

Solid form

50% form

Control wedge form:

Tone values

Laser focus

Resolution

Plate measuring instrument

e.g. Techkon DMS

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Exposure quality

Check exposure consistencyacross the full plate

Check brush pressure

Every day, every laser (ideally)

© 2011 WAN-IFRA Roland Thees, Page 128

Exposure: What must be compared?

L R

Imager 1

L R

Imager 2

Use Siemens star to check 9 positions of each plate and laser focus

Each imager with its 2 plate positionsTone value precision in an imager: ± 2%

Deviation imager to imager: ± 2%

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Minimize differences between imagers

All laser are different - and they age

Avoid different laser manufacturers or different technical specifications

Lasers should have a similar level of utilisation

When one laser is replaced, its recommended to exchangeothers also

© 2011 WAN-IFRA Roland Thees, Page 130

-5,0

0,0

5,0

10,0

15,0

0 5 10 20 30 40 50 60 70 80 90 100

Linearisation in the RIP

Calculate average values after matching the imagers and positions

All imagers should be calibrated with just one RIP curve

Several RIP curves are recommended if different types of imagersand technologies are used

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Continuous control

Dependent on technology (photopolymer, thermal, silver, UV)

The control wedge permits the operator to simply and quickly carry out random visual checks on important properties

Control wedge outside the printable area on each plate

For example: AGFA DigiControl

Where appropriate, use closed loop control system (e.g. AGFA: Afirma, Nela: PQM+, 2B: PQCS) (see IFRA SR 2.32)

© 2011 WAN-IFRA Roland Thees, Page 132

Continuous control: e.g. by AGFA DigiControl

Gray dots for positive plates (Lithostar, Thermostar): neutral from 2x2

Negative plates: display of working point

First adjust to right laser power

Image the DigiControl with the right laser power on the correct position

Working point is e.g. C (see example)

Move to left side (e.g. B): over exposure or under development

Shift to right side: dense imaging or overdevelopment

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AGFA DigiControl

Reasons for shifts:

Changes in the laser energy

Becomes darker as laser energy increases

Focus changes

Details become darker if focusing fades

Becomes darker as developer ages

© 2011 WAN-IFRA Roland Thees, Page 134

Continuous control: Siemens Star

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Plate parameters

Plate dimensions: ISO 12635:2008

Length

Width

standardised Thickness: 0.28 mm +/- 0.01 mm

Parallelism

Influence of roughness on water distribution

© 2011 WAN-IFRA Roland Thees, Page 136

Surface of a new plate

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Plate after 135000 impressions(under normal conditions)

© 2011 WAN-IFRA Roland Thees, Page 138

Plate after 60000 impressions(under poor conditions)

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Dot loss during print production

Not well exposed border disappears in print

Tonal loss can not be avoided during print run

No standard available: When is a plate unusable?

Influences on plate durability from the printing procedure:

Pressure in the printing gap

Printing blanket

Materials (ink, paper)

Chemicals (water additives, cleaners)

© 2011 WAN-IFRA Roland Thees, Page 140

Dot loss in print

Lifecycle of a plate

50

60

70

80

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Reasons for dot gain

Optical dot gain:

Greatest share of dot gain

Paper surface

Light intensity

Dot size (l/cm)

Dot shape

Paper

Paper

© 2011 WAN-IFRA Roland Thees, Page 142

Reasons for dot gain

Mechanical dot gain:

Ink film thickness

Printing blanket (thickness, hardness)

Nip pressure

Ink (viscosity, emulsification)

Paper properties (roughness, volume, hardness)

Absorption behaviour (paper, ink)

Color sequence

Plate Print

Paper surface

Blanket

Raster dot

squeezing

Paper

Blanket

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Calculation of dot-gain curves

Preconditions:

Exposure and development ok

Tone loss of the plates is known and stored in the RIP

Target densities are known (maximum print contrast)

Printing towers adjusted: no slurring/doubling, provision of forme rollers and film roller, blanket thickness, etc.

Use stable plate phase of plates(>6000, <40000) for test prints

© 2011 WAN-IFRA Roland Thees, Page 144

Test print 1 – document status

Use linearised plates

50% file = 54% on plate before printing = 50% between 6000 and 40000 copies

Note materials used (film, type of plate, plate thickness, ink, water additives, printing blankets, etc.)

Print correctly:

Densities

Ink-water balance

Calculate tonal increase curves after e.g. 6000 impressions and at least 5 hours drying

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Test print 1 – Non-acceptable dot-gaincurves of several printing units

0

5

10

15

20

25

30

35

40

45

50

0 10 20 30 40 50 60 70 80 90 100

Tone steps from 0 to 100%

© 2011 WAN-IFRA Roland Thees, Page 146

Test print 2

Use RIP tone curves for platemaking

Print correctly:

Densities

Ink-water balance

Several prints are necessary to cover all towers and to have a statistical basis

Check tone curves after e.g. 6000 impressions and at least 6 hours drying time

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Dot-gain compensation:

Input the required ISO 26% dotgain curve in the RIP-software, e.g. Harlequin Calibration Manager (intended press) for CMYK

Example:50% + 26% = 76%

© 2011 WAN-IFRA Roland Thees, Page 148

Dot gain compensation: actual press

Input the average tone increase from test print 2

Fingerprint (actual press)

One curve for all colors or four curves (for Cyan, Magenta, Yellow and Black each)

Example:50% + 32.7% = 82.7%

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Dot-gain compensation: activate settings

Select calibration for the linearised plate

Select ideal press (ISO 26 curve, intended press)

Select actual press

RIP calculates the correct tone values based on these3 calibration curvesExample:50% file = 47% Film

= 53% Plate= 76% Paper

© 2011 WAN-IFRA Roland Thees, Page 150

Test print 3

Verify that all parameters are correct

Print again correctly

26% dot gain curve must be achieved (+/- 2%)

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Check dot gain curves

Tone increase convergence between the towers by:

Different printing blankets (hardness, thickness)

Correct contact pressure

Same materials (paper, ink, fountain solution additives)

If tone increase is generally too high or too low, adjust screen definition as necessary

Cortina

FM screen

© 2011 WAN-IFRA Roland Thees, Page 152

Grey balance

Optimisation in 0,5 % steps of the dot gain compenasation curve

CMY = 2,33%

CMYK = 4,35%

21,33

20,67

25,00

0

5

10

15

20

25

30

0 10 20 30 40 50 60 70 80 90 100

Dot gain

in %

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Optimising gray balance

Original Cuboid CMY gray patches composition in accordance with ISO:

Quarter-tone (10% C, 8% M, 8% Y)

Mid-tone (30% C, 24% M, 24% Y)

Three-quarter tone (50% C, 42% M, 42% Y)

With Ink Saver software, black replaces CMY values

Grey balance should be easier to achieve: ΔC* absolute < 3

© 2011 WAN-IFRA Roland Thees, Page 154

Color gamut

Size of required colorgamut is dependent on INCQC category

Better with sufficient paper white and optimized colordensities

Insufficent results to be discussed with the Ink supplier

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Diagonal mis-registershould be < 0.15 mm (max.: 0.30 mm) on all pages

Measuring elements

Visual

Measuring instrument-150

-100

-50

0

50

-100 -50 0 50 100

MagentaYellowBlackCyan (ref)

Measure color register

© 2011 WAN-IFRA Roland Thees, Page 156

Optimise color register

Fluctuations due to:

Platemaking

Fan-out: change of web speed

Fan-out: different swelling behaviour of paper

Web tension

Wear & tear (e.g. register pins, plate locks)

Operator (plating-up, use image corrector)

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Optimise color register

Advantages due to:

RIP scaling

Within the plate

Dependent on the cylinder position

FM screen (“only” optical advantage)

Video alignment at plate-making

Camera adjustment, satellite printing units, waterless

Image corrector (manual, speed-dependent, closed loop)

Automatic plate changing system

Set fan-out to production speed

© 2011 WAN-IFRA Roland Thees, Page 158

Press control

Preset based on RIP data corresponding to actual materials

Start-up curves for typical material combinations

1. Ink ductor curve (Cortina: temperature)

2. Fountain solution curve

Different curves for warm/cold press

Different curves for typical material combinations (plates, ink, paper, fountain solution additive, blankets)

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Ink ductor curves example

New ink ductor curves 09.02.2005

-5

0

5

10

15

20

25

30

35

40

45

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

Speed [R/h]

Ope

ning

Val

ue [%

]

15. Black 16. Cyan 17. Magenta 18. Yellow

© 2011 WAN-IFRA Roland Thees, Page 160

Set ink ductor curves

1. Check inking system and ink duct

2. Print waterless using dummy plates

3. Medium ink key opening

4. Copy removal in steady state at certain speeds (8, 12, 25, 40 revs./h)

5. Evaluate densities

6. Set curves

7. Test new curves

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Damping system curves example

New water curves, 09.02.2005

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

Speed [R/h]

Ope

ning

Val

ue [%

]

15. Black 16. Cyan 17. Magenta 18. Yellow

© 2011 WAN-IFRA Roland Thees, Page 162

Set damping system curves

1. 3 testformes: low, medium, high ink coverage

2. Use medium ink key opening/presetting data

3. Copy removal in steady state at certain speeds (8, 16, 24, 32, 40 revs./h)

4. Find setting above the point of smearing

5. If there is no special cold-start adjustment: apply a little more water at start-up speed

6. Test interaction of all curves

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Speeding up the Press

Carry out pre-inking

Allow for press reaction time

Use densitometer for ink setting

Read back only correct values (correct densities, correct speed) for adjusting the press presetting

© 2011 WAN-IFRA Roland Thees

Thank you for your attention.

Roland Thees, Industrial EngineerProject Manager Consulting

WAN-IFRA GmbH & Co. KG, DarmstadtTel.: +49 6151 733 788

[email protected]


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