The Art and Science of Color Management

Living in a World Without Color(bars)

John Seymour Principal Research Engineer QuadTech The Art and Science of Color Management

Living in a World Without Color(bars)

John Seymour Applied Mathematician QuadTech The Art and Science of Color Management

I don't want to live in a world without love or grief or beauty or color bars, I'd rather die.

Dana Winter, Invasion of the Body Snatchers The Art and Science of Color Management Why no colorbars?

1. Colorbars aren’t welcome The Art and Science of Color Management Why no colorbars?

Color patches can hide in a flap The Art and Science of Color Management Why no colorbars?

What if there is no flap? The Art and Science of Color Management Why no colorbars?

No color patches

Hershey’s has a

2.0 DECMC tolerance The Art and Science of Color Management Why no colorbars?

No color patches The Art and Science of Color Management Why no colorbars?

Color patches The Art and Science of Color Management Why no colorbars?

Magazines are trimmed

Colorbars can hide in the trim The Art and Science of Color Management Why no colorbars?

Newspapers are not trimmed

Colorbars can run, but they can’t hide The Art and Science of Color Management Why no colorbars?

Where is the eye drawn? The Art and Science of Color Management Market research

2009 – QuadTech sales force collected

142 newspapers, twelve countries The Art and Science of Color Management Market research Belgium Metro Hyderabad Times of Montreal La Presse Mumbai Economic Times Montreal Le Journal Delhi Economic Times Korea Chosun Ilbo Montreal Les Affaires Pune Economic Times Korea Donga report China Guangzhou Daily Economic Times Korea Korean Economic Santo Domingo Listin Diario Lucknow Economic Times Korea Mailgungie Manchester Daily Express Hyderabad Economic Times Korea Segai Ilbo London Daily Express Chennai Korea Ecoprint Delhi Times Manchester Daily Mail Korea World Journal Mumbai Manchester Daily Telegraph Wisc. Rapids Daily Tribune Noida Hindustan Times London Daily Telegraph USA Dow Jones Chennai Indian Express London Evening Standard Noida Indian Express London Guardian Jacksonville Florida Times Union Pune Indian Express London Observer Miami Miami Herald Navi Mumbai Indian Express Manchester Times New York NY Daily Times Nagpur London Times Pune Lokmat Finland Lansi-Savo Sarasota Sarasota Herald Trib Kolhapur Lokmat Mumbai Lokmat France La Depeche du Midi 4 German nationals Mumbai Nimes Le Fiagro (Nimes) Clave Paris Le Fiagro (Paris) Germany De Morgen Cochin France Le Progress De Standard Germany Darmstädter Echo De Tijd Trivandrum Malayala Manorama Jalandhar Samachar Diario Libre Kozhikode Financial Times Mathrubhumi Kolkatta Anand Bazar Patrika guardian Pallakkad Mathrubhumi India Herald Tribune Calicut Mathrubhumi Agra Het Laaste Nieuws Navi Mumbai Midday Noida Dainik Jagran Hoy Mumbai Midday Ludhiana Dainik Jagran Independent Mumbai Varanasi Dainik Jagran France La Province Mumbai France Le Figaro Jalandhar Dainik Jagran Delhi France Le Monde Delhi Dainik Jagran Jalandhar Punjab Kesari France Le Soir Ludhiana Dainik Jagran Ludhiana Punjab Kesari England Telegraph Meerut Dainik Jagran Mumbai Ratnagiri Times USA The Times Hyderabad Pune Sakaal LA Times Chennai Deccan Chronicle Sandesh Chicage Tribune Bangalore Mumbai Sandhyanand Cleveland Plain Dealer Mangalore Deccan Herald Kolkatta Telegraph New York Times Dharwad Deccan Herald Pittsburgh Catholic Pondicherry Madurai The Hindu Salem Dinakaran Cochin The Hindu Pittsburgh Courier Coimbatore Dinakaran Trichi The Hindu Pittsburgh Post Gazette Madurai Dinakaran Vijayawada The Hindu Pittsburgh Tribune Review Trichy Dinakaran Delhi The Hindu San Francisco Chronicle Vellore Dinakaran Chandigarh Washington Post Tirunelveli Dinakaran Jalandhar The Tribune Chennai Dinakaran New Delhi The Tribune USA Chronicle of Higher Ed Madurai Mumbai Times of India USA Jewish chronicle Chennai Dinamalar Delhi Times of India New York Village Voice Coimbatore Dinamalar Pune Times of India Washington Sports Weekly Ahmedabad Kolkata Times of India Washington USA Today Mumbai DNA Lucknow Times of India USA Barron's Weekly India DNA Money Bangalore Times of India USA Wall St. Journal New York Times The Art and Science of Color Management Market research

How many had color patches?

CMY Just Just None Gray Solids Halftones Full 57 61 42 1 9

40% 43% 30% 1% 6%

Q: Why do they add up to more than 100%? A: Overlap – e.g. use of gray and solids The Art and Science of Color Management Market research

What color patches did they have?

CMY Just Just None Gray Solids Halftones Full 57 61 42 1 9

40% 43% 30% 1% 6%

Ok with using full color bar

94% are not ok The Art and Science of Color Management Market research

What color patches did they have?

CMY Just Just None Gray Solids Halftones Full 57 61 42 1 9

40% 43% 30% 1% 6%

Not interested in quality??

60% are interested in quality … but only 6% use the full colorbar The Art and Science of Color Management

Color bars? We ain't got no color bars! We don't need no color bars! I don't have to show you any stinking color bars!

Treasure of the Sierra Madre The Art and Science of Color Management Image-based color control

Currently at least five vendors

QuadTech AccuCam Mitsubishi Diamond Eye EAE Loop QI IDS Grafikontrol Colorscan TKS - rumored

Several million dollars development X 6 companies = >$10M The Art and Science of Color Management Image-based color control

Currently at least ten printers Newsprinters (Knowsley and Broxbourne) 5+10 Sankei 16+? Yomiuri 110 Nikkei ?? Chunichi ?? Nikkan Sports Printing ?? Polaris (Alesund) ?? Freie (Chemnitz) 3? Transcontinental (San Francisco and 3 Montreal) Corelio (Brussels) ??

Roughly 150 systems… maybe $15M? The Art and Science of Color Management Image-based color control

$25 M spent to get color quality without color bars

Why?

Isn’t the newspaper market shrinking?

Newspaper printers that survive must reduce labor costs print semi-commercial work The Art and Science of Color Management Why measure in the work?

1. Colorbars aren’t welcome 2. Circumferential variation The Art and Science of Color Management Why measure in the work?

Are they all the same color? Copied from presentation by Franz Sigg at TAGA 2007 The Art and Science of Color Management Why measure in the work?

Also stolen from presentation by Franz Sigg at TAGA 2007 The Art and Science of Color Management Why measure in the work?

DE of circ variation Cyan – 2.2 DE Magenta – 2.3 DE Yellow – 5.0 DE Black – 2.0 DE

ISO Tolerances 50% to 100% of tolerance window! Density equivalents

Stolen from my own presentation at TAGA 2007 The Art and Science of Color Management Colorbars don’t predict the work

Papers with similar results

Siljander, Roger, and Richard S. Fisch, “Accuracy and Precision in Color Characterization,” 2001 TAGA Proceedings

Sigg, Franz, “Noisy Dot Gain”, 2007 TAGA Proceedings

Breede, Manfred, “The Effect of Ink Film Thickness Variation on Color Control in the Circumferential Printing Cylinder Direction of Offset Presses”, 2007 TAGA Proceedings

Motaal and Sikander, “Repeatability of Ink Transfer and Color Management Lithography”, 2009 TAGA Proceedings

The Art and Science of Color Management Why measure in the work?

1. Colorbars aren’t welcome 2. Circumferential variation 3. Standard patches don’t predict much of CMYK The Art and Science of Color Management Some fun data

• 102 Newspaper printers applying for SNAP certification • IT8 target from each (928 patches)

“An Analysis of the Current Status of Process Control for Color Reproduction in Newspapers”, Seymour, Stanton, 2011 TAGA The Art and Science of Color Management Correlation of measurements

Some printers leaned heavy on cyan solid

C90 heavy

Not heavier on K40 Also a bit heavy on C80 M10

Heavier on C60, M60, Y50, K20? The Art and Science of Color Management Correlation of measurements 8

6

4

2

0 0 50 100 150 200 250 300 M100 M90 -2

-4

-6

-8

-10 Comparison of variation between M100 and M90 The Art and Science of Color Management Correlation of measurements

8 r2 = 0.8221 6 R² = 0.8221

4

2

0 -10 -8 -6 -4 -2 0 2 4 6 8 10

-2

-4

-6

-8

Comparison of variation between M100 and M90 The Art and Science of Color Management Correlation of measurements r2 = 0.8221

r is the correlation coefficient

82% of the variation is “explained”

82% of the variation is shared The M100 patch is a good proxy for the M90

Comparison of variation between M100 and M90 The Art and Science of Color Management Correlation of measurements

If I want to track 90% magenta, I can watch the magenta solid

The M100 patch is a good proxy for the M90 The Art and Science of Color Management Using patches as a proxy

Good proxy – sharing at least 50% of the variation

Fair proxy – sharing at least 25% of the variation The Art and Science of Color Management Using patches as a proxy

Solid M - good proxy for 10 of 928 patches

Solid Good proxy Fair proxy

Cyan 6 26 Magenta 10 61 Yellow 9 35 Black 3 9 C+M+Y+K 28 131

Four solids predict 3% of CMYK values The Art and Science of Color Management Using patches as a proxy

Mama always said life was like a box of solid patches. You never know what you're gonna get.

Forrest Gump The Art and Science of Color Management Using patches as a proxy

Patch set Num Good proxy Fair proxy patches Four Solids 4 28 (3%) 131 (14%) 4 Solids + 40% 8 186 (20%) 587 (63%)

ISO 12647-2 requirements only speak for 20% of the colors The Art and Science of Color Management Why measure in the work?

1. Colorbars aren’t welcome 2. Circumferential variation 3. Standard patches don’t predict much of CMYK 4. Tony the Tiger, flesh tones, mastheads The Art and Science of Color Management Who uses colorbar data?

1. Press crew 2. Press office 3. Print buyer 4. Prepress The Art and Science of Color Management Customers of the data Needs data to run the job well Familiar with density / dot gain / trap Hard to use CIELAB

1. Press crew 2. Press office 3. Print buyer 4. Prepress The Art and Science of Color Management

I don't care what they say, I won’t stay in a world without color bars.

In a World Without Colorbars, by Paul McCartney (made famous by Peter and Gordon) The Art and Science of Color Management Customers of the data Needs data to run the job well Familiar with density / dot gain / trap Hard to use CIELAB Press diagnostics 1. Press crew Familiar with density / dot gain / trap Insurance against customer complaints 2. Press office 3. Print buyer 4. Prepress The Art and Science of Color Management Customers of the data Needs data to run the job well Familiar with density / dot gain / trap Hard to use CIELAB Press diagnostics 1. Press crew Familiar with density / dot gain / trap Insurance against customer complaints 2. Press office 3. Print buyer Proof that job ran properly 4. Prepress The Art and Science of Color Management Differing viewpoints The Art and Science of Color Management Customers of the data Needs data to run the job well Familiar with density / dot gain / trap Hard to use CIELAB Press diagnostics 1. Press crew Familiar with density / dot gain / trap Insurance against customer complaints 2. Press office 3. Print buyer Proof that job ran properly 4. Prepress

So… what is needed to prove this? The Art and Science of Color Management Customers of the data Needs data to run the job well Familiar with density / dot gain / trap Hard to use CIELAB Press diagnostics 1. Press crew Familiar with density / dot gain / trap Insurance against customer complaints 2. Press office 3. Print buyer Proof that job ran properly 4. Prepress Adjustment of plate curves The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Requirements for metrics

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Gap analysis

Data to run job Training Know density / dot gain / trap Better software Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Gap analysis

Dense City Colorimetropolis is on an island is the mainland

Paint Textiles Spot colors Tennis court lighting The Art and Science of Color Management Gap analysis

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Better software Insurance for complaints Prove that job correct Adjust plate curves

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Gap analysis

Solid ink density TVI from the image

We’re working on it… The Art and Science of Color Management Gap analysis

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves Better software

Density-based colorbar CIELAB-based in the work The Art and Science of Color Management Gap analysis

Adjust plate curves We’re working on this, too…

US patent 7,032,508 The Art and Science of Color Management Gap analysis

Data to run job Know density / dot gain / trap Don’t know CIELAB Press diagnostics Insurance for complaints Prove that job correct Adjust plate curves

Will be taken care of Density-based colorbar CIELAB-based in the work The Art and Science of Color Management

Cold hearted orb that rules the night Removes the color bars from our sight Red is gray and yellow, white But we decide which is right And which is an illusion

Nights in White Satin, The Moody Blues The Art and Science of Color Management Changes to 12647-3

ISO standard for newspaper printing

Current version requires

CIELAB values of solids and overprints Tone Value Increase targets The Art and Science of Color Management Changes to 12647-3

Latest draft requires one of… CIELAB values of solids and overprints Tone Value Increase targets --or-- Target CIELAB values for CMY gray and K midtone --or-- Some set of measurements from the work The Art and Science of Color Management ISO 15339-1

All CMYK values specified in CIELAB via a characterization data set The Art and Science of Color Management

Imagine there’s no color bars It isn’t hard to do Nothing to adjust your ink keys to…

Imagine, John Lennon The Art and Science of Color Management How to do CCIW?

Four methods for color control in the work

1. Find the patch in the image 2. Convert RGB to CMYK 3. Tease out black with IR 4. CIELAB optimization

From “Closed loop color control in the work”, Seymour, Tiltman, Nelson, 2010 TAGA The Art and Science of Color Management Find the patches in the image Method #1

Pseudo-color bar The Art and Science of Color Management Find the patches in the image Method #1

? The Art and Science of Color Management Convert to CMYK Method #2

Capture RGB image A measurement at each pixel Convert to CMYK of C, M, Y, & K ink

Compare against correct CMYK

Add up errors

US patent 7,040,232 The Art and Science of Color Management Convert to CMYK Method #2

Capture RGB image Is this just standard color separation?

Convert to CMYK No

Color separation finds one of many possible Compare against combinations of CMYK to correct CMYK give the RGB value.

CCIW needs to know how much of each ink is there. Add up errors The Art and Science of Color Management Convert to CMYK Method #2

Test image

Cyan Magenta Yellow Black The Art and Science of Color Management Convert to CMYK Method #2

Capture RGB image

Can’t get Convert to CMYK four pieces of information Compare against from three correct CMYK

Add up errors The Art and Science of Color Management Tease out black using IR Method #3 Capture RGB+I image

Black can be seen in IR; CMY are invisible Convert to CMYK Once you know black, you can take black out of RGB image Compare against correct CMYK

Add up errors QT patents 5,412,577 and 5,724,259, Man Roland patent 5,530,656 Goss patent 5,903,712 May be used in other color control systems The Art and Science of Color Management RGB+I method Method #3 • Requires special camera • Weighting of errors does not match the human eye The Art and Science of Color Management RGB+I method Method #3

Tiny changes in C, M, and Y will cause big visual shifts The Art and Science of Color Management Methods 1, 2, and 3

Paradigm - Goal: correct amount of each of the inks

If this is the goal… you need to measure the amount of each ink The Art and Science of Color Management Methods 1, 2, and 3

Paradigm - Goal: correct amount of each of the inks

What is the correct amount? Is it the correct cyan density of a C40 M60? The Art and Science of Color Management CIELAB optimization Method #4 Alternate paradigm - Goal: correct color

If this is the goal… you need to measure the color The Art and Science of Color Management All pixels request color change Method #4

Live image Target image Brighter

More saturated

Redder

Darker The Art and Science of Color Management Every pixel gets a vote Method #4 The Art and Science of Color Management CIELAB optimization Method #4 Current L*a*b* values Estimate and evaluate Overall DE Target color change L*a*b* values DC, DM, DY, DK To minimize this Adjust these values

US Patent 5,967,050 The Art and Science of Color Management How to do CCIW?

Four methods for color control in the work

1. Find the patch in the image 2. Convert RGB to CMYK 3. Tease out black with IR Target CMYK amount 4. CIELAB optimization

Target CIELAB value The Art and Science of Color Management Measuring in the work

Ideal measurement system

1. Image at 300 DPI 2. Image whole web 3. 32 spectral channels 4. Up to 3,000 FPM 5. Really inexpensive The Art and Science of Color Management Measuring in the work

Possible design options

Device Channels DPI All the web? RGB area 3 300+ DPI No camera The Art and Science of Color Management Measuring in the work

Possible design options

Device Channels DPI All the web? RGB area 3 300+ DPI No camera Point spectro 30+ 1 DPI? Yes, in a spiral The Art and Science of Color Management Measuring in the work

Possible design options

Device Channels DPI All the web? RGB area 3 300+ DPI No camera Point spectro 30+ 1 DPI? Yes, in a spiral Hyperspectral 30 2 DPI Yes linescan The Art and Science of Color Management Measuring in the work

Possible design options

Device Channels DPI All the web? RGB or RGB+I 3 or 4 300+ DPI No area camera Point spectro 30+ 6 DPI? Yes, in a spiral Hyperspectral 30 2 DPI Yes, in blocks linescan Six channel 6 25 DPI Yes, in pages linescan camera The Art and Science of Color Management QuadTech AccuCam

300 DPI 25 DPI 6 DPI

Can read text, Lost detail, Color starts can see wrinkles still color faithful to suffer The Art and Science of Color Management QuadTech AccuCam

95th percentile

1.5 DE94

Measurement accuracy on 1,296 CMYK patches The Art and Science of Color Management Summary • Color bars not always welcome • Color bars don’t ensure correct image • Customers of data can be satisfied • Standards are following • Various algorithms for CCIW • Various possible measurement devices

The Art and Science of Color Management Thanks for listening!

John Seymour Principal Research Engineer QuadTech [email protected]