Printing Standards & Specifications

Question 0

What’s does GRACol stand for ?

Answer 0

General requirements and applications for commercial offset lithography

Question 1

What does SWOP stand for?

Answer 1

Specifications for web offset publications

Question 2

What does SNAP stand for?

Answer 2

Specifications for newsprint advertising production

Question 3

What is ISO 12647

Answer 3

1. The official international printing standard
2. Defines ink/paper colour, dot gain etc.
3. Universal basis for print specs (SWOP, GRACol, ICC etc.)

Question 4

WhT Re Colorimetic Specifications?

Answer 4

Defined by characterization data sets

Must be tested yearly

Question 5

What is densitomerty?

Answer 5

1. Measures ink quantity but not ink colour
2. Convenient for CMYK process control
3. Less useful for colour matching
4. Doesn’t measure appearance

Question 6

What is Colorimetry?

Answer 6

1. Measures ink colour precisely
2. Less convenient process control
3. Excellent for colour matching
4. Measures visual appearance

Question 7

Colorimetry basics involve this formula

Answer 7

CIELab = numerical definition of human vision

Question 8

For the CIELab:

Answer 8

Lowest L value = 0 (black)

Highest L value = 100 (white)

Question 9

What is the unit of CIELab colour

Answer 9

Delta E

Question 10

What does 0 delta E mean?

Answer 10

It means there is NO different in colour (only in a perfect world)

Question 11

What delta E value = limit of visual perception

Answer 11

Less than 1.0

Question 12

What delta E value = typical proof tolerance

Answer 12

Less than 2.0

Question 13

What delta e = good press tolerance

Answer 13

Less than 5.0

Question 14

Delta E is the..

Answer 14

Difference btwn colour on swatch to match colour on press sheet

Question 15

SWOP is intended for

Answer 15

Web offset publications on coated paper

Question 16

GRACol was developed for

Answer 16

Commercial sheetfed offset lithography

Question 17

SNAP is intended for

Answer 17

Newspaper industry (including ads printed in newspaper)
Coldset newspaper printing

Question 18

What is G7

Answer 18

New method for calibrating a press or proofer
Bases of both current SWOP11 and GRACol 7
Based on visual metrics
Brings photographic principles to press
Controls Gray balance and neutral tonality (which TVI doesn’t)

Question 19

G7 is named for…

Answer 19

G = gray scale
7 = seven ISO ink solids
Trade mark of IDEAlliance

Question 20

Limitations ofmTVI calibration

Answer 20

1. Identical CMY TVI curves can produce different neutral contrast and/or gray balance
2. Doesn’t control gray tonality b/c ignore 3-colour ink trap
3. CMY TVI curves don’t control gray balance b/c they ignore ink trap, opacity,hue

Question 21

How many scales does G7 calibration measure?

Answer 21

2 scales

1. K-only
2. Gray balance

Question 22

By using look up tables (LUTs) G7 calibration controls….

Answer 22

Neutral contrast & gray balance

Question 23

Benefits of G7 are…

Answer 23

1. Directly Controls neutral tonality & gray balance using same RIP curves as TVI
2. CMY gray scales measures visual affects 3-colour trap for precise gray tonality
3. CMY gray scale measures and controls the combined effects of ink trap, ink opacity and hue for precise gray balance

Question 24

G7 ink =

Answer 24

ISO ink

Question 25

G7 paper =

Answer 25

ISO paper

Question 26

All G7- based printing methods share

Answer 26

1. Same gray balance & tonal contrast

2. Less need to convert files separated for another process

Question 27

A specification is based on

Answer 27

A standard

Question 28

IDEAAlluance does not make

Answer 28

Standards

Question 29

IDEAlliance’s mission is to

Answer 29

Promote & implement standards like ISO 12647-2

And develop moods where needed