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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 Memberroland.thees@wan-ifra.org
© 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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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Cuboid color target values in category 1(coldset on standard paper)
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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)
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ISO tone value increase (TVI)
Category 1
26% curve
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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
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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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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
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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
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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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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
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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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© 2011 WAN-IFRA Roland Thees, Page 163
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
roland.thees@wan-ifra.orgwww.wan-ifra.org
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