2. G7 Master Qualification Basic Training
1. Idealliance and the Value of G7
2. G7 Principles- Gray Balance & Tonality
3. G7 Target Conditions - Global Standards and Specifications
4. G7 Color Managed Workflows
5. G7 Process Control and Quality Assurance
6. Using G7 with Color Management – Expectations and Value
7. G7 Compliance & G7 Master Submission
8. Education and Innovation
Creators of ISO Standards
in the World
ISO Experts & Unique
Status of Liaison A to ISO
Largest Certifying
Body in the World as
Measured by ISO
Most Recognized
Industry Training in
the World
12 Global Offices
Globally
Transformative
Partners
9. G7 Master Qualification for Print Facilities
G7® Grayscale Compliance:
This is the fundamental level of G7. Regardless of printing technology, if we can ensure that a
printer or press prints the neutral tone ramp well, then all other colors will tend to fall into line
more easily.
G7® Targeted Compliance:
This is a secondary level of G7. G7 Targeted is achieved when G7 Grayscale is achieved.
The solid ink measurements for primaries and secondaries (KCMY and RGB) and substrate color
are also within spec to one of the G7-based TARGETED color spaces.
G7® Colorspace Compliance:
This is the third level of G7 compliance and the most stringent.
G7 Colorspace includes all the requirements of the G7 Targeted level (and therefore the G7
Grayscale level) adds the matching to an entire Reference Print Condition, E.G. IT8.7/4.
10. Idealliance G7 Programs
G7 Expert Certification
Individuals trained, tested, and authorized
by Idealliance to train G7 Masters
• Skilled, tested and proven leaders in print
production
• Users of global standards to match proof-to-
print
• Committed to reducing costs, speed to market
• Improve their client’s brand image
11. G7 Expert Certification
A G7 Expert has demonstrated expertise in the field of color management, process and quality control for proofing
and printing utilizing the G7 methodology & specification. A G7 Expert is able to analyze color and print related
issues and take corrective action to bring systems and processes in control to a set method, standard or
specification with repeatable, predictable results. A G7 Expert has attended and successfully completed an
Idealliance G7 Expert Training with a minimum level of 90% proficiency. Certification is valid for two years.
Individuals certified as a G7 Expert must hold individual, or be employed by an organization holding, Idealliance
membership. Recertification is required every two years. The G7 Expert must recertify by successfully completing
the Recertification Review & Exam within 90 days of certification expiration.
12. G7® Value and Benefits
• G7® is Idealliance’s industry-leading set of
specifications for achieving gray balance
• G7 achieves visual similarity across all print
processes.
G Represents Gray
7 Represents CMYK+RGB
14. G7® Technical Definition
• Defines a universal neutral appearance for printed
grays.
• Calibrates based on Tonality and Gray Balance
Offset Inkjet Flexo
15. G7® Leading Global Specification
Revised into ISO 12647-2
Pantone® Color Bridge is G7® calibrated
Used since 2006 by thousands and thousands
of printers globally
Specified by hundreds of major international
brands
16. • Customers expect consistent color
• Brand color requirements
• Across multiple presses and locations
• Reprinting same job or graphics
• One target regardless of device
• Proof to Press
• Customers expect consistent color
• Paper agnostic
• Predictable color accuracy
• Measurable, objective quality
G7® Value Print Service Providers
Consistency
17. G7® Value Print Service Providers
• Reduces make-ready time
• Reduces labor and waste
• All devices print to same target
• Sustaining expectations is easier
• G7 is an ANSI/CGATS specification for
targeting gray balance
• Agile – Load balancing work
• Shift production lines confidently
Efficiency
18. G7® Value Brands
• Color consistency reinforces trust
• Color variation erodes brand loyalty
subconsciously
• Color is an essential part of brand loyalty
• Color is a crucial factor in quality perception
• Color enhances consumers’ experience
with a product
• Color is an emotional attribute of a brand
Consistency
19. G7® Value Brands
• Reduced design cycles
• Reduced cost of design proofing
• Eliminate the need for on-site press checks
• Faster design-to-print cycle
• No fuss job reprints
Efficiency
20. G7® Value Supply Chain
• Simple data exchange to communicate
quality needs
• Concise expectations for acceptable color
• Aligns supply chain partners to the same
sheet of music
Communication
22. • Based on human visual perception
• Defines a universal “near neutral"
for the printed appearance of gray
• Single Color (black) vs. Multi Color (CMY)
• Controls
• TONALITY and
• GRAY BALANCE
What is G7?
23. • Defines a simple method for
calibrating CMYK printing devices.
• Simple, fast, one-step process to
calibrate any print system
• (Single Color (Black) to CMYK)
• Applicable across all CMYK print
technologies, inks and substrates
What is G7?
25. • G7 is a gray management system
• Managing gray balance & tonality using simple CMYK calibration
curves
• G7 is not a ”color management" system
• Complete color management requires G7 + additional color
management. Does not replace ICC Profiles, Process Control
• Tone reproduction improve when grays are correct
What is G7 NOT?
26. • Gray balance + tonality are controlled with
simple 1-D curves.
• G7 produces a shared neutral appearance on
all printing systems.
The G7 Method: Core Concept
27. • Achieving G7 Grayscale compliance with
CMYK (1-D) curves alone, and no extra color
management
• Individual (C+M+Y+K) curves can be imported
from external software (LUTs, DLPs, etc.) or
calculated by the printing system (Print Engine,
RIP, etc.)
The G7 Method: Core Concept Application
29. • Based on Tonal Value Increase (TVI) of separate CMYK
ink scales
Dot Gain (TVI) calibration
30. Traditional Dot Gain (TVI) calibration achieves...
• With Standard Dot Gain Curves (TVI)
RIP Curves TVI Curves
+ =
31. • A color swatch can have the same TVI but different
tonality
50% black ink, 20% TVI
TVI does not compensate for tonality
32. • Dot Gain is a ratio of ink film reflectance (density)
• Not a direct indicator of "appearance“
• Any two points can vary in appearance
TVI does not compensate for tonality
33. • Any two swatches can have the same TVI, but vary in
appearance.
Example:
Dot Gain alone (TVI) does not control gray balance
CTVI = 18% MTVI = 18% YTVI = 18%
34. • Gray balance is also impacted by various other print
variation
Dot Gain alone (TVI) does not control gray balance
Green/blue “cool” caused by print variation : Trapping,
Sequence, Ink Hue, Opacity?
35. TVI = Inconsistent Grays = Inconsistent Color
Digital Ink Jet Offset
Before
After
36. • G7 (gray balance) is calibrated on two major print
functions
What makes G7 different?
3 Color
Process
(CMY
only)
Black (K
only)
G7 TVI
37. • Tonality and Gray Balance
G7 Aligns according to 2 Basic Visual Concepts
T
onality Gray balance (Near
Neutral)
41. • Neutral Print Density Curve
G7 NPDC: What is NDPC?
Neutral
Density
Gray Halftone dot % (CMY v K)
42. Origin of G7 Neutral Print Density (Tonality)
• G7 was developed as the ND vs. dot % of nine GRACoL
research print trials
Neutral Print
Density Curves
50. Substate Relative Gray Balance with G7
Appearance of gray matches the substrate it is printed on
Cool Substrate Neutral White Point Warm Substrate
Example: Poly Film Example: Uncoated
Board
51. Substrate Absolute Gray Balance with G7 (abs; a*, b* = 0)
Grays are inconsistent with substrate/paper white
Cool Substrate Neutral White Point Warm Substrate
Example: Poly Film Example: Uncoated
Board
57. • Stabilize the system.
• Produce a sample print. (No color management)
• Measure your calibration target. Ex. P2P
• Calculate RIP curves. By software or with formula (graph paper)
• Produce a second print with new RIP curves. (No color management)
• Check Results of Second Press Run.
• Create ICC (if needed).
G7 Calibration Steps
58. • Idealliance Certified G7 Systems
• A system that achieves G7 Grayscale by the G7 Method with 1-D curves alone
• Excludes systems that simulate G7, e.g. by color management, GCR, channel mixing, etc.
• Current list available at www.idealliance.org/g7systems
Automatic G7® Curve Calculation
59. Automatic G7® Curve Calculation: Systems
• FUJIFILM ColorPath™ Sync®
• Heidelberg Prinect® Color Toolbox
• CHROMiX/HutchColor Curve2™ /
Curve3™ / Curve4™
• Alwan Dynamic Printer
Calibration™
• ColorGATE Productionserver
• Color CareTM v 2.2.1
• Caldera Print Standard Verifier G7
• Kodak ColorFlow Software
• EFI Fiery Color Profiler Suite v.4.9 /
v.5.0
• PRISMAsync Color Print Server for
Canon imagePRESS
• ORIS Lynx
• Bodini Systems pressSIGN 8
• AGFA PressTune 8
• Koenig & Bauer QualityPass 8
• PRISMAsync Color Print Server V6
/ V7
• ONYX Media Manager with G7
v18.5
• AGFAAsanti 4.2
• Mellow Colour PrintSpec 4Canon
Visit www.Idealliance.org for details
70. HC Highlight Contrast – 25k or 25c, 19m, 19y
HR Highlight Range – 50k or 50c, 40m, 40y
SC Shadow Contrast – 75k or 75c, 66m, 66y
G7 Neutral Print Density Curves (NPDC)
71. Finding control patches in the P2P target
SC
75c 66m 66y
75k
HR
50c 40m 40y
50k
HC
25c 19m 19y
25k
72. Quick check of NPDC in mid-tones
50% gray ND relative to paper
Add paper ND to get target ND
HR_cmy = 0.54
HR_k = 0.50
Highlight Range (HR)
73. Evaluate NPDC in highlights
25% gray ND relative to paper
Add paper ND to get target ND
HC_cmy = 0.25
HC_k = 0.22
Highlight Contrast (HC)
25
74. Evaluate NPDC in shadows
75% gray ND relative to paper
Add paper ND to get target ND
SC_cmy = 0.90
SC_k = 0.90
(varies with DR)
Shadow Contrast (SC)
75
75. • HR and SC aims vary with tonal range (DR)
• But HC (25%) aims are constant
• (Same for all density ranges)
Target ND aims vary according to Tonal Range (density)
77. • G7 doesn’t add extra work (in theory)
• All devices must be calibrated anyway
• For some work, G7 is enough without profiles
• G7 extends the life of a profile
• If the device drifts, G7 brings the gray scale back to how the profile
was made - less need to re-profile
Why profile & G7?
78. • G7 can improve the quality of ICC color management
• Does the heavy lifting of tonality and gray balance
• Lets the profile concentrate on subtle color accuracy
• G7 controls highlight detail better than ICC
• Due to limited precision of IT8.7/4 and other profiling targets
Why profile & G7?
79. • G7 reduces the need for re-profiling
• ICC profiling is slower, more expensive than calibration
• ICC profiling can be DANGEROUS
Why profile & G7?
80. • Color is subjective
• ALL printing systems vary to some extent
• A proof is a “simulation” of a perfect press
• Every press run is slightly different
• Evaluating “quality” is not an exact science
• Quality is proportional to price
Reality check
81. An offset pressrun is a combination of science, skill and
luck
Over 100 variables, only about 10 of which can be
controlled at press time
Ink Jet printing is roughly 100x more stable than offset!
• That's why most proofing systems use ink jet
Printing is not an exact science
82. • ISO-standard papers are hard to find!!!
• Papers are bluer than ten years ago
• Paper color affects image color
• Don't expect a good proof simulation if you print on
non-standard paper
Non-standard papers
84. • G7 does NOT guarantee perfect color
• Nothing does!
• G7 manages gray balance and tonality
• G7 does not compensate for…
• Inconsistent materials
• Unstable processes
• Color gamut limitations
• Bad printing
G7 Limitations
85. • Like any calibration method, G7 does not eliminate
printing variation
• For best results, measure more than one sheet to
minimize variations on the device
• Offset G7 calibration (and profiling) requires more than
one test.
•
Ideally, repeat the exercise 2 or 3 times and take the average
G7 Cautions (continued)
86. • CMYK+OGV
• Adds Orange, Green and Violet to
CMYK inks
• Commonly used in packaging
(mostly offset and flexo)
• XCMYK
• Extended gamut method for 4-
color (CMYK) inks
• Methodology, data set and
profiles released by Idealliance in
2016
Extended Gamut Print Strategies
87. • Offset or Flexo:
• Print CMYK inks to high densities on good paper
• Use FM screening to enhance pastels
• Calibrate to G7
• Digital
• Match the XCMYK profile (free at Idealliance.org)
XCMYK method
90. G7 Master Compliance Levels
• G7 Grayscale
• G7 Targeted (Absolute or Relative)
• G7 Colorspace (Absolute or Relative)
91. G7 Grayscale Compliance
• G7 grayscale calibration
• Average w∆Ch:
• Maximum wCh:
• Average w∆L*:
• Maximum w∆L*:
< 1.5
< 3.0
< 1.5
< 3.0
• Minimum Level of Compliance
• Non-standard inks
*G7 Master Pass/Fail Requirements, Version 36, Aug 2019
92. G7 Targeted Compliance
• G7 Grayscale plus...
• Inks match a defined CRPC
• ∆E00 ≤: CMY 3.5, K 5, RGB 4.2
• CRPC can be standard or custom
• (Send custom data with application)
• Example: G7-calibrated offset
• Standard Level of Compliance
93. G7 Colorspace Compliance
• Elite Level of Compliance
• G7 Targeted plus IT8.7/5 tolerances...
• Proofing:
≤ 1.5 ∆E00
≤ 1.5 ∆E00
≤ 3 ∆E00
≤ 5 ∆E00
• Substrate
• All patches average
• 95th percentile
• Maximum
• Press:
• Substrate
• All patches average
• 95th percentile
≤ 3 ∆E00
≤ 3.5 ∆E00
≤ 5 ∆E00
94. G7 Colorspace Compliance
• CRPC can be public (e.g. GRACoL) or custom*
*Custom submissions must include IT8.7/5 data
• Expected performance:
• Good neutral match
• Good solid color match
• Good pictorial color match
95. G7 Targeted & Colorspace - Relative
• Same as G7 Targeted or G7 Colorspace but utilized with
non-standard white point substrate
• Different color or lightness
• Ink solids are compared to the defined CRPC, modified
by "SCCA" (Substrate-Corrected Colorimetric Aims)
• NOTE: Highlights, Color, & Grays , colors and grays
shift towards substrate color and brightness
96. • ∆E < 1.5 = Excellent Proof
• ∆E < 2.0 = Average Proof
• ∆E < 3.0 = Average Press (offset)
• Average of all patches within a
characterization target
• IT8.7/5 (TC1617) / IT8.7/4
Typical Delta E tolerances : Proof & Press
97. • On-site training requirements
• Supported by online tutorials and other material
• Affidavit signed by Expert and Master employee
• Samples must be produced by employee, not Expert
G7 Master procedures summary
Requirements Affidavit Samples
98. • Each device aims for a named compliance level:
• Grayscale, Targeted, or Colorspace
•
• Print samples must contain latest QR code
• www.idealliance.org - changes quarterly
G7 Master print samples
G7 sample prints must be made by the
Master employee, not the Expert
99. Recommended:
• G7 Verifier
Also accepted:
• P2P51 or P2P25
Sample targets - G7 Grayscale & Targeted
100. •
•
•
Sample targets - G7 Colorspace
• Recommended:
• TC1617, IT8.7/5
• Also accepted:
• G7 Verifier or P2P51 or P2P25 + IT8.7/4
+
or or
102. All the best for your Master certification
Learn more about G7® at
www.idealliance.org/G7
ISHANT KALKAL *G7 Expert - (Pre-sales Manager) RSG Solutions Pvt. Ltd. New Delhi
E-Mail Address – ishant.Kalkal@rsgsolutions.co.in / Mobile - +919310196639
