1. Color Management for Production Printing
Connectivity Master Full Training Module
See notes for version changes
Date of change
Version History
Description
1.0.a
Initial version (no changes)
1.1.a
Corrected typing errors, simplified English
Created by: Group L&D Version:1.1.a Classification: Ricoh Family Group Internal use only

2. Objectives
After completing this training you should be able to explain:
the basics of color management.
some of the terminology used in production color printing.
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3. Requirements PC running Windows. This presentation.
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4. Pre-requisites and exam
There are no pre-requisites.
At the end of this course, you can do the exam on WICE.
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5. Module Overview Introduction What is Color Describing Color
Color Management
Color Management Systems
Proofing
Profiling
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6. 1. Introduction
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7. Introduction to Color Management
Color is important to businesses based on their specific needs.
For instance, many organizations have a corporate or brand color that is a key element of their brand identities.
These colors must be accurately reproduced, regardless of whether or not the branded items are printed using offset or digital printing or other technologies.
However, to achieve this accurate reproduction, people have to rely on color management, which has always been regarded as something difficult and only for color geeks.
This presentation will show you the fundamentals of color and color management in, hopefully, an easy way.
It will define color terms and it will explain the tools and processes behind color reproduction.
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8. 2. What is Color
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9. Color Basics
Color is the visual sensation produced in response to selective absorption of wavelengths from visible light.
To see an object it must either emit light, as the sun does, or reflect it from another source, such as the moon reflecting sunlight.
Color is generally described using additive or subtractive models.
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10. Light So what exactly is light?
Light is actually a form of electromagnetic radiation.
What is electromagnetic radiation, then?
Electromagnetic radiation has a dual nature as both particles and waves, as explained on the next slides.
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11. Electromagnetic Wave
The traditional way is to describe light as being an electromagnetic wave.
This wave has amplitude, which is the brightness of the light, wavelength, which is the color of the light, and an angle at which it is vibrating, called polarization.
The wave theory of light was happily adopted and accepted until it was found to fail to explain some observed and measured phenomena.
Polarization
Light waves can vibrate in many directions.
Those that are vibrating in one direction - in a single plane such as up and down - are called polarized light.
Those that are vibrating in more than one direction - in more than one plane such as both up/down and left/right - are called un-polarized light.
Two phenomena that upset the wave theory:
Photoelectric effect.
Blackbody radiation.

12. Quantum Theory
In terms of the modern quantum theory, electromagnetic radiation consists of particles called photons.
Photons are packets ("quanta") of energy which move at the speed of light.
In this particle view of light, the brightness of the light is the number of photons, the color of the light is the energy contained in each photon, and four numbers (X, Y, Z and T) are the polarization.
Notes
Actually, photons are not particles in the physical sense that we normally associate with that word.
Rather, they consist of discrete bundles of energy, which gives them particle-like characteristics.

13. Electromagnetic Spectrum
Both interpretations are correct, but the wave viewpoint is primarily used, since it is a more useful description.
The human color perception range is between ultraviolet (400nm) and infrared (700nm).
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14. White Light
Sir Isaac Newton was the first to realize that white light actually contains all colors.
A nice tool to show that is the prism.
Note
Nature also has a prism: the rainbow.

15. RGB
Light with a wavelength between 600 and 700 nm is known as red light.
Light with a wavelength between 500 and 600 nm is known as green light.
Light with a wavelength between 400 and 500 nm is known as blue light.
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Blue
Green
Red
400
500
600
700

16. Seeing Color
When we see light, there are 3 important elements that influence color perception:
The light source.
The colored object.
The eye.
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Light source
Light sensor
(human eye)
Colored object

17. Eye Mechanism Eyes have a structure similar to cameras.
Two types of light-sensitive cells in the retina: rods and cones.
There are three types of cone cells, each sensitive to a specific range of wavelengths (red, green and blue).
The eye is made up of many complicated parts that help us to perceive light, shape and color.
When you look at an object light enters your eye through the cornea.
The light is focused by the lens and is then projected onto the retina.
The retina registers the image and sends this visual information to the brain through the optic nerve.
As we could see it earlier in this module the image is captured on the retina upside down.
The brain automatically converts the image so it appears correct.

18. Perceiving Colors Transmitted Light Reflected Light We can see:
reflected light (intrinsic color).
transmitted light (luminous color)
Color is perceived by the reflection of light off an object.
The way a color looks is relative to the viewer.
Transmitted Light
Reflected Light
The colors that a person can see are classified into two groups.
In one group, light is emitted directly from an object, such as the sun, electric bulbs, and monitors.
In the other group, light is reflected from an object.
materials on the object absorb some portions of the light and reflect other portions.

19. Color Perception (1/2) The light source emits light.
This is known as luminous color.
The object absorbs colors and reflects colors.
The human eye perceives color based on the objects that light is reflected from.
This light is known as intrinsic color.
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20. Color Perception (2/2) Perception of colors depends on:
The light-source.
The observer.
the surrounding colors.
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21. The light source
The color of a light source is described by its temperature.
Color temperatures are measured using the Kelvin scale.
Warmer temperatures emit bluish light.
Cooler temperatures emit reds.
The temperature scale is calculated based on the amount of light emitted by a blackbody at any given temperature.
Blackbodies are theoretical objects that are perfectly black when cold. At zero degrees Kelvin they absorb all light cast upon them; however, as they heat up, they begin to emit light—first red, then yellow, then white and finally blue.
While perfect blackbodies do not exist, most solid objects are a good approximation of blackbodies. Think of the coils on an electric heater, the filament of an incandescent bulb, and even the sun and stars.
Kelvin is similar to Celsius. The unit intervals are the same; however, zero K is equal to -273 degrees Celsius.
Warmer temperatures emit bluish light. Cooler temperatures emit reds. This runs contrary to most people’s color intuition. Blue is usually seen as a cold color.

22. Metamerism
Metamerism is an illusion in which two or more colors appear identical under certain light sources, but are different from each other under other lights or to a different observer.
This is a common problem in the color printing business.
That is the reason why many professionals use a light cabinet to evaluate their prints.
Notes
Light cabinets allow you to evaluate a print using different light sources.
Most cabinets will allow you to change the light tubes, so you can switch from D50 (5000 Kelvin or soft daylight) to D65 (6500 Kelvin or noon daylight), UV or whatever the cabinet manufacturer has to offer.
Light cabinet

23. Paper with optical brighteners, seen using a black light
Fluorescence
Some atoms and molecules have the ability to absorb photons of a certain energy level, and emit photons of a lower energy level.
This is called fluorescence, and can sometimes change one type of visible (or even invisible  ultraviolet) wavelength into another visible wavelength.
Many paper manufacturers add fluorescent brighteners (optical brighteners or bluing agents) to whiten the slightly yellowish paper.
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Paper with optical brighteners, seen using a black light

24. Additive Colors (RGB)
By combining Red, Green and Blue light we can create all the colors of the visible light-spectrum.
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25. RGB Color Monitors CRT LCD
With devices that emit light by themselves, color is represented by the proportions of the R, G, and B light.
This method is called additive color mixture.
R, G, and B are called the three primaries of light.
CRT
LCD

26. Subtractive Colors (CMY)
Using Cyan, Yellow and Magenta toners we can create colors on paper.
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27. Complementary Colors
In the color theory, two colors are called complementary if, when mixed in the proper proportion, they produce a neutral color (grey, white, or black).
Red is the complement color of cyan.
Green is the complement color of magenta.
Blue is the complement color of yellow.
R G B
C M Y
RGB are not good as primary colors for subtraction.
A pigment that has one primary color will absorb the other two primaries. For example, red paint absorbs green and blue, and reflects red light back to our eyes. Similarly, green paint absorbs red and blue but reflects green light.
Adding red, green, or blue pigments together will cut out more of the light coming back to the eye, making what we see rather dull, so we cannot produce many colors like this. (For example, it is impossible to get yellow.)
The best subtractive colors are those that absorb only one of the three primary colors (red, green, and blue) that stimulate the cells in the retina. These colors are Cyan, Magenta, and Yellow.
Absorption of Primaries
Each of these absorbs its complement and reflects the others.
Cyan absorbs Red but reflects Green and Blue Magenta absorbs Green but reflects Red and Blue Yellow absorbs Blue but reflects Green and Red
CMY are known as the 'subtractive primaries'.
Each of the subtractive primaries absorbs one of the additive primaries producing the widest gamut possible with just three colors.
When combining different proportions of the additive primaries makes it possible to produce millions of different colors, overprinting different amounts of the subtractive colors also makes a large gamut with a lot of colors.

28. White Paper Reflection
In theory, white paper reflects all colors.
This is a theoretical statement, because different brands of paper have a different color.
This is why in color management it is very important to know what paper we are using.
This is not only true for the output, but also for the original.
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29. Yellow Toner Absorbs Blue Light
Yellow is the complement of blue.
Yellow toner absorbs blue light and reflects green and red light.
The reflected “G” and “R” light are seen as yellow.
No additional notes R G B Y C M R G B C M Y

30. Magenta Toner Absorbs Green Light
Magenta is the complement of green.
Magenta toner absorbs green light and reflects blue and red light.
The reflected “B” and “R” light are seen as magenta.
No additional notes R G B Y C M R G B C M Y

31. Cyan Toner Absorbs Red Light
Cyan is the complement of red.
Cyan toner absorbs red light and reflects green and blue light.
The reflected “B” and “G” light are seen as cyan.
No additional notes R G B Y C M R G B C M Y

32. Mixing Subtractive Colors
Equal amounts of magenta and yellow toner produces red.
Equal amounts of cyan and yellow toner produces green.
Equal amounts of magenta and cyan toner produces blue. Y C M
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33. Process Black In theory, equal amounts of C, M and Y produce black.
This black is called “Process Black”.
In reality, it is virtually impossible to produce true black using cyan, magenta and yellow toner.
Depending on the used toners or inks, the result can vary form deep blue to be brown or gray.
When all three colors: cyan, magenta and yellow are blended together in equal pro-portions, the result is that all the wavelengths of light are absorbed, and black is produced.
This black color is referred to as “processed black,” and depending on the purity of the colors for cyan, magenta, and yellow will actually appear to be a very deep blue or brown.
Pure black
Process black

34. Under Color Removal (UCR)
One way of reducing the “Process Black” problem is UCR or Under Color Removal.
UCR replaces an equal amount of yellow, cyan and magenta with black toner, but only in dark, near neutral colors.
Advantages:
Lower toner consumption.
Better reproduction of black.
Disadvantage:
The image lacks depth if high UCR ratios are used like in Letter Mode.
That is the reason why 100% UCR is not used very often.
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100% UCR
60% UCR

35. Gray Component Removal (GCR)
GCR has the same function as UCR.
The difference between GCR and UCR is that GCR starts at lower image densities.
It can be used for neutral and non-neutral colors that are either light or dark
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36. UCR vs GCR The pictures show the difference between UCR and GCR.
You can clearly see that GCR starts earlier with color replacement.
UCR
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UCR – UnderColor Removal – odstranění podkladové barvy
GCR- Gray Component Replacement – nahrazení šedé složky
Str.195
GCR

37. 3. Describing Color
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38. Chapter Overview Introduction to Describing Color Color Wheels
HSB/ HSL
Named Colors
Spot Colors
CIE Color Model
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39. 3.1 Introduction to Describing Color
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40. Describing Color Color is often difficult to communicate about.
The reason is that the words we use to describe color are vague and frequently misunderstood.
Not only are technical terms such as "value," "saturation" and "chromaticity" confusing but even simple words such as "bright," "pure," "shiny" and "dim" are hard to use accurately.
Even the experts struggle without a set of standardized definitions.
We need numerical models to manipulate and predict colors, simply because we use computers.
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41. Color Models
Both scientists and artists have long struggled to come up with a model that would be able to describe al colors.
Famous people like Newton, Goethe and Maxwell have tried.
Some modern models are based on the Munsell Color System, developed by Albert H. Munsell.
His model uses different values of hue, brightness (value), and saturation (chroma) to define colors more accurately.
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42. Color Terminology – Hue
Hue is the property of color that we are actually asking about.
For example, when we talk about colors that are red, yellow, green, and blue, we are talking about hue.
Different hues are caused by different wavelengths of light.
Therefore, this aspect of color is usually easy to recognize.
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Hue Contrast – different hues
Hue Constant – different colors, same hue

43. Color Terminology – Chromaticity
Chromaticity describes the purity of a color.
That means there is no white, black, or gray present in a color that has high chroma.
These colors will appear vivid and pure.
Chromaticity is related to and often confused with saturation.
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High chroma – very shiny and vivid
Low chroma – achromatic, no hue
Constant chroma – medium chroma, similar vividness, less purity than top image

44. Color Terminology – Saturation
Related to chromaticity, saturation tells us how a color looks under certain lighting conditions.
For instance, a room painted a solid color will appear different at night than in daylight.
Over the course of the day, although the color is the same, the saturation changes.
This property of color can also be called intensity.
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Saturation constant – same intensity, different hue
Saturation contrast – various levels of fullness, same hue

45. Color Terminology – Value
When we describe a color as "light" or "dark", we are discussing its value or "brightness“, “lightness” or “luminance”.
This property of color tells us how light or dark a color is based on how close it is to white.
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Low Value, Constant – same brightness level
Contrast of Value – grayscale = no chroma
Contrast of Value – big differences in brightness

46. Brightness or Lightness
In color science, there is a distinction between lightness and brightness, although the 2 words mean the same.
The strict definition of lightness: lightness is the brightness of an object relative to an absolute white reference.
This means that lightness ranges from dark to light, with specific definitions of black and white as the limits.
We can measure lightness and assign specific numerical values to it.
Brightness ranges from dim to bright with no real limits.
It is just a subjective sensation in our heads.
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HSL and HSB are derived from the Munsell Color System, describing Lightness and Brightness

47. 3.2 Color Wheels
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48. Color Wheels
The color wheel or color circle is the basic tool for combining colors.
The first circular color diagram was designed by Sir Isaac Newton in 1660.
The color wheel is designed so that virtually any colors you pick from it will look good together.
Over the years, many variations of the basic design have been made, but the most common version is a wheel of 12 colors based on the RYB (or artistic) color model.
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49. 3.3 HSL and HSB
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50. HSL and HSB/HSV
Derived from the Munsell Color System are the HSL and HSB models.
They are the two most common cylindrical-coordinate representations of points in an RGB color model.
HSL stands for hue, saturation, and lightness, and is often also called HLS.
HSB stands for hue, saturation, and brightness, and is also often called HSV (V for value).
The major difference is in the shape of the 2 models.
HSB uses 1 cone to display all colors, while HSL uses 2 cones.
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51. HSL HSL uses 2 cones to display the colors.
Used for example in Microsoft Office.
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HSL in MS Office

52. HSB Sliders in Photoshop
HSB uses a single cone.
Used for example in Adobe Photoshop.
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HSB Sliders in Photoshop

53. 3.4 Named Colors
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54. Named Colors
In essence, a named color is a color with a name and an RGB value.
Example: the color crimson, with RGB values 220, 20, 60.
This is used for instance for building websites.
A complete list of the color names supported by all major browsers can be found on the internet.
In the printing industry, the use of RGB values is not used very often, since most printing devices use CMYK toners/ inks.
Instead, spot colors are used.
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55. 3.5 Spot Colors
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56. Spot Colors
In offset printing, a spot color is any color generated by an ink (pure or mixed) that is printed using a single run.
Technically speaking, the 4 colors that the offset uses to print are also spot colors.
However, generally speaking, when we talk about spot colors, we mean a color other then CMYK.
More specifically, any color generated by a non-standard offset ink, such as metallic, fluorescent, spot varnish, or custom hand-mixed inks.
Spot colors are also named colors, because all spot colors have a name.
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57. Spot Color Library
The spot colors are contained in a library: the spot color library.
There are several industry standards in the classification of spot color systems
To name a few:
Pantone
The dominant spot color printing system in the United States and Europe.
Toyo
A common spot color system in Japan.
DIC
Another common Japanese spot color system.
HKS
A German color system.
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58. Pantone
As said before, Pantone is the dominant spot color system in Europe and the US.
The Pantone Color Matching System (PMS) is a standardized color reproduction system.
Since all Pantone colors are standardized, different manufacturers in different locations can all refer to the Pantone system to make sure colors match.
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59. Pantone Guide
The Pantone guides are sets of thin cardboard sheets, containing all Pantone colors.
There are several guides, for specific media (coated, uncoated etc.).
In PMS, all Pantone colors have a unique number.
For instance, PMS 130 is a yellow tint.
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60. Problem
The Pantone spot color library was never designed, nor intended, to be used as a way to specify colors that will be printed using CMYK toners or inks.
As a result, because of the gamut differences, CMYK process simulations of the Pantone library can only provide an approximation and in the majority of cases, deliver disappointing results.
CMYK
Spot
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61. Pantone Colors
However, most of the world's printed material is produced using the CMYK process, so there is a special subset of Pantone colors that can be reproduced using CMYK.
These are labeled as such within the company's guides and are called the Pantone Process Colors.
The rest of the Pantone system's colors cannot be accurately simulated with CMYK.
Instead, 13 base pigments are used (15 including white and black) mixed in specified amounts.
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Example of the Pantone Process library in Photoshop

62. CMYK Equivalents
You will find the Pantone Process Colors, including their CMYK equivalents on the Pantone Guides.
Important to know is that these CMYK values are based on offset inks, and not on CMYK toners or inkjet inks.
The Pantone color may not be accurately reproduced when you print these CMYK values on a Ricoh color laser printer.
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Pantone color swatch
Pantone color printed

63. Built-in Library
Instead of relying on the indicated CMYK values, many printer/ controller manufacturers use their own built-in spot color libraries.
The printer will use the values as indicated by the built-in library instead of printing the spot color with the CMYK equivalents as indicated by the spot color manufacturer.
This ensures a better match, since the built-in library is custom-made for each printer type.
Some Ricoh devices can be connected to a Fiery or Creo printer controller.
These controllers allow operators to fine tune the CMYK values for spot colors, to achieve an even better match.
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64. 3.6 CIE Color Model
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65. Tristimulus
The term tristimulus refers to experiments and measurements of human color vision involving three color stimuli, which the test subject uses to match a target stimulus.
The most comprehensive model has been defined by the CIE (Commission Internationale de l’Eclairage) back in 1931.
In fact, it is so comprehensive that it forms the basis for color management as we know it.
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66. The CIE Color Model
The CIE color model is device-independent, which allows us to describe color in such a way that it can be reproduced consistently and accurately on different equipment.
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67. CIE Chromaticity Diagram (CIE XYZ)
This diagram represents the colors of the spectrum.
All colors that can be recognized by the human visual system are within these curves.
A vertical axis (Y) represents brightness, to include browns, grays, etc.
Important to know is that CIE XYZ does not factor in the non-linearity of the human eye, so the distances are distorted.
Background information:
CIE Chromaticity (CIE XYZ) tristimulus values are used to calculate the CIE xyz values.
This is a plot of x against y.
x + y + z = 1, so we do not need to show z.
The xyz values are the CIE chromaticity values.
Chromaticity values describe a color stimulus, without considering the brightness.

68. The CIE LAB Model
CIE LAB is the second of 2 systems adopted by the CIE.
It is an attempt to reduce the distortion in color distances.
LAB is based on XYZ, but is non-linear, to try to mimic the human senses.
L is a luminance scale.
a and b are color axes.
Although not perfect, it is the most useful system today.
There are many other models like CIE LCh, CIELUV, CIE xyZ, etc. but they are not commonly used.
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69. Delta E (∆E), Delta H (∆H), Delta T (∆T)
The CIE Color Model also allows for computations of color difference.
These differences can be measured as delta E, delta T or delta H.
This can be important, since it allows users to actually measure any differences in color, rather then relying on visual inspection.
Think of comparison between output of a digital printer and an offset press, between actual print and target or between pages in a single job.
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∆E, ∆H and ∆T in EFI Color Profiler Suite

70. Color Bar or Job Slug
To measure the difference in color, you can print a control bar alongside the actual print job.
Color Verifier of EFI Color Profiler Suite
Note
Some vendors call this feature the control bar, while others call it a job slug (or rather, part of a job slug).

71. Delta E (∆E)
Delta E (Euclidian distance) is defined as the difference between two colors in an L*a*b* color space.
The following delta E values are valid universally:
0 - 1: A normally invisible difference.
1 - 2: Very small difference, only obvious to a trained eye.
2 - 3: Medium difference, also obvious to an untrained eye.
3,5 - 5: An obvious difference.
> 6: A very obvious difference.
Note
The human eye is more sensitive to some areas of color and less sensitive to others.
Colors in highly saturated areas are assessed less strongly than colors along the gray axis, where the human eye is particularly sensitive.
This fact is not sufficiently taken into account when calculating ΔE.

72. Delta H (∆H)
The absolute color difference between two samples is known as the hue difference (delta h*).
This measured value is used to calculate the fractional value of delta E, which evolves from the hue difference between two color samples alone.
Differences in brightness are ignored during the calculation of delta H.
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73. Delta T (∆T)
Delta T describes the colorimetrically calculated dot gain defined by ISO
Delta T stands for the tone differences between the reference and the result.
These tolerances can only be measured for the primary colors, e.g. 100% cyan.
It is not possible to calculate delta T values for colors composed of a mixture of cyan, magenta, yellow and black.
Example:
If you have a reference output of 40% cyan and a measurement of nearly 50%, the delta T result for this patch is around 10%.
This corresponds to a dot gain of around 10%.

74. LAB Limitations
Although the CIE LAB model is pretty good, it does have some limitations.
For one, it is not as uniform as it was supposed to be.
Changing one of the primary colors by a certain increment does not always produce the same degree of visual change.
Another limitation is that CIE LAB assumes that a straight hue-angle line will produce constant hues, changing only in saturation, but unfortunately that is not the case.
Note
Hue shift is most prominent in the blue/ purple area, but does appear in other areas as well.
Hue shift from purple to blue

75. PowerPoint Blue
Ever had problems with printing for instance PowerPoint slides with a blue background?
Since the blue of the background is so highly saturated, most printers cannot print it.
Instead, following a straight line to pure white, the first color that is within the printer’s gamut will be used.
Since this is a very common problem, many print manufacturers have a built-in compensation for this phenomena.
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Printer gamut
Instead of blue, purple will be printed
Highly saturated blue, impossible to print

76. 4. Color Management
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77. Color Management (1/2)
In digital imaging systems, color management is the controlled conversion between the color representations of various devices, such as digital cameras, scanners and printing devices.
The primary goal of color management is to obtain a good match across color devices.
For example, colors from a photograph, taken with a digital camera, should look pretty similar on a monitor and on the printed output.
In other words: WYSIWYG or What You See Is What You Get.
Note that true WYSIWYG will not be possible.
However, with proper color management, you can produce a close and consistent output, which, with little learning, allows you to predict the final output.
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78. Color Management (2/2)
Another important goal of color management is to make it usable.
In the “old days”, color management was not needed, because all images were scanned by professional operators, on a single scanner which produced CMYK output, optimized for a particular printer.
This system worked because it was a closed loop that dealt with only one scanner and one printer.
But today, we have thousands of different input and output devices which have to be connected.
And worse, they still need to produce predictable results and need to provide WYSIWYG, one way or the other.
Color management deals with this in a smart way, as you can see in the next slide.
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79. With or Without Color Management
Old style “Color Management”.
Color Management with device independent color space (PCS).
N input
M output
N input
M output
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PCS
N x M conversions
N + M conversions

80. ICC
The most popular color management systems make use of the ICC (International Color Consortium) workflow.
It makes use of 4 basic components:
PCS.
Profiles.
CMM.
Rendering intents. 80
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Monitor Profile
Input Profile
Output profile
CIE Lab
Reference Color Space

81. PCS
The PCS or Profile Connection Space allows us to give a color an unambiguous numerical value in CIE XYZ or CIE LAB.
It is a device independent color space which defines color as we actually see it.
The PCS is used as the “hub” through which all color conversions travel.
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82. Profiles
Profiles describe the relationship between a device’s RGB or CMYK control signals and the actual color it produces.
In other words, it defines the CIELAB values that corresponds to a given set of CMYK or RGB numbers.
Profiles can describe:
A single device, such as an individual scanner, monitor or printer.
A class of devices, such as Apple Cinema Displays, Euroscale presses etc.
An abstract color space, such as Adobe RGB (1998) or sRGB.
But whatever it describes, in essence it is just a look-up table.
Video Gamut RGB
Adobe RGB (1998)
sRGB
Note
The look-up table does not contain the numbers of every possible combination of RGB/CMYK to Lab or vice versa.
The reason is that the profiles would be too large to handle.
Example:
RGB, 8 bit means 16,7 million RGB values.
If you dedicate 3 bytes for each definition, the profile would be about 50 MB!
That’s why interpolation and calculation is used to compute al the combinations.
This is done by the CMM.

83. CMM
The CMM or Color Management Module is the engine of color management.
It is a piece of software that performs all the calculations needed to convert the RGB or CMYK values.
It works with the color data contained in the profiles.
Note that although there are several CMMs, for instance from Adobe, Agfa, Heidelberg, Kodak, EFI, which are designed to be interoperable and interchangeable, they do tend to vary, especially when profiles are tailor-made for a particular CMM.
This means that you can get different results from using different CMMs.
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84. Rendering intents The ICC specification includes 4 rendering intents.
These are, simply put, different ways of handling “out of gamut” colors, so colors which cannot be reproduced by an output device.
The 4 intents are:
Presentation or Saturation.
Photographic or Perceptual.
Relative Colorimetric.
Absolute Colorimetric.
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Example of rendering intents on a Fiery controller

85. Gamut?
In digital printing, when we talk about “gamut” we mean the color space of a device.
Devices can be divided into 2 categories:
RGB devices like scanners, monitors, digital cameras etc.
CMYK devices like laser printers, offset etc.
Normally, in general, a CMYK printer device color space will be smaller (less saturated and fewer colors) than a RGB capture device color space.
Note
Yes, a typical CMYK printer will have a smaller gamut than for instance a monitor.
But that does not mean that a monitor is capable of displaying all the colors that a CMYK printer can produce.
Especially highly saturated cyan (and the blues and greens that lie next to cyan) can be printed, but are difficult or even impossible to be displayed on monitors.
A typical RGB color space
A typical CMYK color space

86. Gamut Mapping
When printing, a source gamut has to be translated into a destination gamut.
For instance, when printing a photograph, taken with a digital camera, the gamut of the camera has to be translated into the gamut of the printer.
Some colors from the camera may be outside of the gamut of the printer, so these colors need to be shifted inside the gamut of the printer.
This process is called “gamut mapping”, and is done through color management.
As explained before, 4 rendering intents can be chosen to do the gamut mapping, so let us have a look at what they actually do.
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87. Presentation Also called Saturation Rendering.
It maps the saturated primary colors in the source space to the saturated primary colors in the target space, without bothering about differences in hue, saturation or lightness.
It is designed for rendering business graphics like pie and bar charts, where we simply want vivid colors and are not particularly concerned as to exactly what those colors are.
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88. Photographic Also called Perceptual Rendering.
It attempts to compress the gamut of the source space into the gamut of the target space.
It de-saturates all colors to bring the out-of-gamut colors into the target gamut while more or less maintaining the overall relationship between colors.
Preserving the relationship between colors helps preserve the overall appearance of images.
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89. Absolute Colorimetric
Also called Match Intent.
Reproduces in-gamut colors exactly, and clips out-of-gamut colors into the closest color at the gamut boundary.
Problems with Abs Colorimetric:
White in the image appears to have a color cast.
Because the relationship between in- en out-of-gamut colors is changes, often the image is destroyed.
Problems with Absolute Colorimetric
It tries to reproduce the source white exactly in the target space. If your target space represents a print and there is a visible paper-white border, an absolute colorimetric print will usually look strange. The white areas in the image will almost always have some color added, but our eye adapts to the paper-white surround, so the image appears to have a color cast.
Secondly, our eyes are much better at evaluating color relationships than they are at evaluating absolute colors. When you clip the out-of-gamut colors in an image to their nearest reproducible hue, you change the relationship between the in-gamut and out-of-gamut colors, which often destroys the image.

90. Relative Colorimetric
Also called Proof Intent.
Similar to Absolute Colorimetric Rendering.
The only difference is that Relative Colorimetric scales the white point of the source to the white point of the target.
Brightness may be modified so that all the brightness levels are within the range of brightness of the destination gamut in use.
Proof intent does not preserve the white point.
For example, the whitest white of a paper is more yellow than the whitest white of a computer monitor. An image converted into the gamut of the printer using relative colorimetric intent would result in all colors becoming more yellow. The white point of the image is moved to match the white point of the printer. All other colors in the image keep their position relative to the white point. This produces an image that more accurately reflects what the printed image will look like. However, the user may find it visually disconcerting.

91. Profiles and CMM
Most color-managed applications let you assign profiles to images and other colored objects.
For example, Photoshop allows you to assign a profile to an image.
When these images are then used in applications like Adobe Illustrator or InDesign, the CMM will use the embedded profiles for correct color management.
Although this is done automatically, most CMMs do allow you to override these embedded profiles when needed.
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Example on a Fiery controller: use embedded profile or select one yourself

92. Shortcomings
Besides all the positive points there are a few negative things about the ICC workflow as well.
The “intelligence” of the ICC workflow lies in the profiles, rather then in the Color Management Module used to connect the source and output profiles.
This can result in inaccuracies or unnecessary desaturation in color conversions.
In some cases, 2 otherwise perfectly fine profiles just seem to cause problems when you use them together.
The next slides will show some other examples of unwanted results.
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93. Black Channel
When converting the source profile into Lab, and from Lab to output profile, the black channel information is lost.
The reason is that Lab is only 3 dimensional, while CMYK is 4 dimensional.
For some users, this is not acceptable.
The work around for this problem is the device link.
Lab
C 60%
M 23%
Y 0%
K 100%
C 12%
M 12%
Y 2%
K 70%
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94. Device Link
A device link will directly connect a source profile to an output profile, without conversion to or from Lab.
The result will be a much more accurate conversion.
It allows preservation for black channel, as well as for pure primaries.
For Fiery controllers, device links can be created with specialized software (EFI Color Profiler Suite, Gretag MacBeth Profile Maker etc).
Other controllers (Creo controllers, for instance) create device links on the fly, when selecting a source and output profile.
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C 60%
C 20%
M 23%
M 16%
Lab
Y 0%
Y 1%
K 100%
K 100%

95. Gamut Mapping
Another example of the ICC workflow flaw is that gamut mapping is not intelligent.
Lets assume you want to print a photograph, taken with a digital camera.
Source profile camera: Adobe 1998.
Output profile: device profile printer.
Lets again assume that all the colors that the camera has shot are all well within the gamut of the printer.
As you print a photograph, it is likely you will choose the photographic rendering intent.
When you press the Print button, without even checking the colors of the photograph, the complete Adobe 1998 gamut will be compressed into the output profile of the printer, thereby unnecessarily changing all colors.
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96. Workaround
Actually, the only available workaround is to use your brains.
Do not blindly select a rendering intent.
For this job, the colorimetric intent was probably a better choice.
Note
Some controllers (Creo controllers, for instance) have an option to automatically select the correct rendering intent.
Since you print a photograph, the controller will automatically use the photographic rendering intent, so do not always rely on automation.

97. CMM and Bad Images
One thing to remember is that color management does not take a bad image and make it look good on output.
It does not eliminate the need for color correction.
What it does is make sure that the image (and all its shortcomings) are faithfully reproduced on the output device.
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98. Color Management and Memory Colors
Memory colors are colors like green grass, blue sky and skin tones.
These colors matter more than others because we have such a strong memory of them.
Even if a print is colorimetrically correct, when for example the skin tones are not what the viewer expects, the image looks wrong.
This is a psychological aspect of human color perception that we cannot put in a model, so color management cannot address this.
This means that sometimes human intervention is needed to correct the output.
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Example of a faithfully reproduced image, which does not look right.

99. 5. Color Management Systems
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100. Chapter Overview Introduction ColorSync ICM WCS Applications
Printer Driver
Color Controllers
Prepress Solutions
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101. 5.1 Introduction
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102. Introduction There are several ways of how to use color management.
All major Operating Systems have a color management system built-in.
Some applications have their own color management system built-in.
Some printer driver have support for color management.
And last but not least, many color controllers have an embedded color management system.
No matter what system you use, it is important to stick to using just one.
Having different CMMs trying to color manage a single job will give you unexpected results.
So which one do you use?
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103. What to Use As with many things in life: it depends.
If you want to print some photographs, taken with your digital camera, on an inkjet printer, connected to your PC or Mac, you can use the color management system of your Operating System or application.
If you have a certain workflow, where PDFs from unknown origins have to be printed on an professional color device, you are probably better of using the color management system of the printer controller.
The next slides will show some highlights of different color management systems.
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104. 5.2 ColorSync
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105. ColorSync
ColorSync is Apple’s implementation of the ICC specification, providing system-level color management of images, documents and devices.
ColorSync is fully integrated into Mac OS X, ensuring that powerful color management tools can be accessed from every application for consistent color.
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106. ColorSync Utility
Every device, connected to Mac OS X, is automatically assigned at least one ICC profile.
In some cases, a single device (e.g. printer) may have several ICC profiles available (a profile for different media types for instance).
In those cases, you can use the ColorSync Utility to manually select the correct profile for each job.
The ColorSync Utility also allows you to view, compare and edit ICC profiles.
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107. Monitor Calibration
While Mac OS X has already assigned a factory profile to your display, calibration of the display based on your environmental conditions is highly recommended.
Mac OS X provides the tools to do this using the Display Calibrator Assistant.
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108. 5.3 ICM
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109. Image Color Matching
ICM is the built-in color management system of Windows 95/98/2000/XP, originally developed by Heidelberg.
Like ColorSync, it provides an OS-level color management system based on the ICC workflow.
Windows 95 and Windows NT4.0 need an application that supports ICC profiles.
Newer Windows versions offer color management support on OS level.
ICM is not as tightly integrated as ColorSync.
In many cases, you have to manually assign ICC profiles (ICM profiles in Windows) to devices.
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110. ICM Profiles
In case of Ricoh products, the needed ICM profiles can be downloaded from the Ricoh-Support website, or created using a profiling application, such as EFI Color Profiler Suite or Gretag MacBeth Profile Maker.
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111. Printer ICM Profile
The correct ICM profile can be assigned to a printer driver in the Color Management tab in the driver.
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112. Monitor Profile
You can assign a monitor profile in the advanced settings of the display properties.
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113. Monitor Calibration
ICM does not provide a tool for monitor calibration.
You will have to rely on 3rd party applications, for instance the EFI Color Profiler Suite or the Eye-one Display from Gretag MacBeth.
Since these tools provide excellent results, it should not be regarded as a show stopper for ICM.
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114. 5.4 WCS
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115. WCS
Starting from Windows Vista, Microsoft introduced a new color architecture known as Windows Color System.
WCS supplements the Image Color Management (ICM) system in Windows 2000 and Windows XP.
The primary reason for the Windows color management architecture is to improve the what-you-see-is-what-you-get (WYSIWYG) quality for printing and imaging.
WCS Provides seamless interoperability with ICC profile-based workflows:
ICC-only transforms run through improved ICM3 CMM.
Mixed ICC & WCS transforms run through WCS CITE.
It is beyond the scope of this presentation to show you all the ins and outs of WCS.
The next slides will show some highlights.
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116. Color Management Tab
The use of WCS is most noticeable in the Color Management tabs in the drivers.
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117. Monitor Calibration WCS has a built-in monitor calibration wizard.
Although it provides acceptable results, it is still recommended to use 3rd party software for calibration.
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118. Conclusion WCS looks promising, but it is not matured yet.
It is to early to make any predictions, so we just have to wait and see what happens to WCS.
One thing that would have to change is that applications like Adobe Photoshop have to be “WCS aware”.
At the moment, you can use Photoshop with WCS by selecting “use icm” in Photoshop.
However, for displaying images on your monitor, Photoshop will still rely on its own icm, using ICC profiles.
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119. 5.5 Applications
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120. Color Management in Applications (1/2)
Some applications like Photoshop, InDesign, Illustrator, QuarkXPress, have a built-in color management module.
These applications know what ICC profiles are and how to use them, at least to some degree.
The Adobe applications use ACE or Adobe Color Engine.
The major benefit of having a built-in proprietary CMM such as ACE is cross platform operability.
No matter if you use these applications on a Mac or on a Windows platform, ACE produces the same results.
Note that many of these built-in CMMs still use ICM or ColorSync to request the current display profile or to find profiles on the system.
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121. Color Management in Applications (2/2)
Although the application may be color managed, the actual color management may still be performed by the operating system through ColorSync or ICM.
Other application vendors insist on implementing color management in their own way, using their own interfaces and terminology, making it hard for users to fully understand what the application is doing.
Luckily, Adobe is one of the vendors who is trying to make color management easier for users, by integrating the same CMM in the applications of the Adobe Creative Suite.
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122. 5.6 Printer Driver
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123. Printer Drivers
When printing to a Ricoh color device, you have to option to use either the RPCS driver (discontinued since the GW2009S controller), the PCL driver or the Postscript driver.
Both the RPCS and PCL driver can only output RGB data, while Postscript can output both RGB and CMYK data.
So when printing CMYK data using an RPCS or PCL driver, it will first be converted to RGB and then back to CMYK.
The PCL driver is excellent for printing to high quality (more than 4-color) inkjet printers because they must be driven by RGB data.
They are not really CMYK because of the additional colors.
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124. Color Management in Printer Driver
Each manufacturer seems to decide a different color management approach for their printer driver.
However, most, if not all, Postscript drivers can use Postscript color management.
Most professionals will therefor prefer to use a Postscript driver.
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Example of a Ricoh RPCS driver

125. Postscript Color Spaces in PDF
For every PDF color space, there is an available Postscript color space.
And since PDF is widely used in the graphic arts market, this also explains why Postscript is the output file format for graphic arts applications.
A corresponding chart for PCL or RPCS would have too many gaps.
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126. In-RIP Color Management
Many printers have a Postscript interpreter built-in.
This ensures true and predictable color.
Even some applications are using a Postscript RIP.
For instance, Adobe InDesign uses the AGM or Adobe Graphics Model.
This is a Postscript RIP, which will “print” the document to the monitor.
This allows “true” WYSIWYG.
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127. Postscript Details
The Postscript driver can send RGB or CMYK data to the printer, but the data can be in CIE color space as well.
ICM can be used in 4 ways:
ICM Disabled.
ICM by Host.
ICM by Printer.
ICM using Printer Calibration.
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128. ICM ICM Disabled means that color management is disabled.
This is the preferred setting when you want color management to be performed by the application (for instance Photoshop).
ICM by Host means that you will use the color management system of the Operating System.
Make sure to attach the correct ICC profile to the printer.
If you select ICM by Printer or using Printer Calibration, the Postscript interpreter in the printer will actually do the color management.
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129. 5.7 Color Controllers
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130. Color Controllers
Instead of relying on Operating Systems or applications, many professionals are now relying on the color management features of their printer controllers.
These controllers have a built-in Postscript interpreter and sometimes even a built-in PDF interpreter (Adobe PDF Print Engine).
Since many professional printers have made the switch to the PDF workflow, these controllers allow a very efficient PDF workflow.
Most professional color controllers like Fiery or Creo controllers are loaded with all sorts of advanced color management features.
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131. Color Controller Features
These controllers have support for:
Calibration
ICC Workflow
Import of custom ICC profiles
Printing of spot colors
Spot color editing
Printing of separations
Simulation printing
Color substitution
Printing of overprints
Imposition
Composition
Preflights
And many more
The next few slides will explain some of these features.
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Example of a Fiery controller

132. Simulation
Professional controller allow you to “simulate” another printer or printing standard.
Just an example:
A lot of printing companies are now printing according to a standard: ISO 12647, which allows printing companies to print predictable and consistent.
On Fiery and Creo controllers you can select an ISO standard profile as a simulation profile, thereby making the printer print according to the same standard.
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133. Overprint
In most cases, when two objects of different colors overlap they knockout -- they will not print on top of each other.
To intentionally print one layer of ink or toner on top of another is to overprint.
Overprinting is sometimes used to avoid the need for trapping and avoid gaps between touching colors.
Overprints can become really difficult to print when you use it in combination with transparencies.
You will need a high end printer controller to print these sorts of things.
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Overprint without transparency
Overprint with transparency and drop shadow
Overprint without transparency with drop shadow

134. Imposition
Imposition is one of the fundamental steps in the prepress printing process.
It consists in the arrangement of the printed pages on the printer’s sheet, in order to obtain faster printing, simplified binding and less waste of paper.
As an example, a 16-page book is prepared for printing.
There are eight pages on the front of the sheet, and the corresponding eight pages on the back.
After printing, the paper is folded in half vertically, folded again horizontally and folded for a third time.
The example below shows the final result prior to binding and trimming.
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135. Example of Imposition on a Fiery Controller
With a few mouse clicks, a 12 page PDF file can be printed as a document setup for saddle stitching.
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136. Preflight
Preflighting is usually the first step in prepress processing.
Preflighting includes any and all standard prepress document additions, font and color changes, and error corrections that can influence a job's passage through the workflow.
This allows you to check if a file can be printed correctly, without wasting time, paper and toner.
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137. Last Stage Editing
On professional controllers, last stage editing is possible.
Think of color corrections, imposition, composition etc.
Since problems can be corrected at a very last stage, this can save valuable time and money.
Files do not have to be send back to the creator, but can instead be corrected on the controller.
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138. 5.8 Prepress Solutions
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139. Prepress Solutions
Prepress solutions are basically proprietary modules that fit into a existing workflow.
Examples of popular systems are:
Prinergy (Creo Kodak)
Prinect (Heidelberg)
Apogee (Agfa)
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140. Benefits
One benefit of using a prepress solution lies most of all in the automation of a workflow.
For example, errors which are detected by preflight can be automatically corrected, without any human intervention.
Another benefit is that it can offer the same workflow for both digital printing and offset printing (hybrid workflow).
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141. Downsides
Basically, there are 2 points to consider, when going for a prepress solution.
First, the price.
It can be quit costly to implement a solution like this.
In time, it will probably save money, but the initial costs can be high.
Second, knowledge.
Implementing the solution will most likely be done by the solution vendor, but even operating the solution requires a great deal of knowledge.
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142. 6. Proofing
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143. What is Proofing?
Proofing is the simulation of the output of one device on another device, such as a printer (hard proofing or monitor (soft proofing).
Needless to say that whatever device you use, it must be properly calibrated, profiled and it must have a large enough color gamut.
Proofing is very popular in the offset world, because printing on an offset press is quite expensive and, generally, takes some time.
To fully understand proofing you will need a basic understanding of offset printing.
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144. Offset or Lithography Basics
The basic principles of offset printing:
Ink is supplied to the plate cylinder.
The plate cylinder has an etched metal or polyester plate. The etched parts of the plate are ink repellant, so the ink will only stick to some parts on the plate.
Ink from the metal plate will be transferred to the offset- or blanket cylinder , which is covered with a rubber blanket
Finally, ink is transferred from the offset cylinder onto paper.
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145. Multiple Colors The previous slide showed just one color.
To print multiple colors, you could either print one color one paper, clean the offset press, remove the metal plate for the first color, attach the metal plate for the second color, fill the offset with the second ink, and start printing the second color on the same paper.
This is, of course, very time consuming, but still widely done.
Another option is to use an offset device with multiple print stations.
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6-Station Man Roland
12-Station Heidelberg

146. Plates
There are many ways in how to create the metal plates, but this is one of the most popular ones:
The operator first creates an image on a piece of transparent polyester (film negative).
The film is placed on top of the metal plate, which has a photo polymer coating.
The metal plate is then exposed to UV light.
The parts of the photographic layer that are exposed to UV light can be etched away using etching liquid.
The parts of the plate that are not etched away (the image) is water repellant but ink will stick to it.
The parts of the plate that are etched away are not water repellant. Because water will stick to this parts, ink will not.
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Části fotografické vrstvy, které jsou vystaveny UV záření můžou být vyleptány pomocí leptací kapaliny.
Části desky, které nebyly vyleptány (obraz) jsou vodoodpudivé ale inkoust se na ně naváže a opačně.

147. CTP or Computer To Plate
Relatively new is the CTP technology, which allows the imaging of metal or polyester plates without the use of film.
The benefits of CTP are:
reduced prepress times.
lower costs of labor.
improved print quality.
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148. Full Color Printing
In offset printing, CMYK inks are used to create a full color print.
Additionally, spot inks may be used for spot color printing.
Magenta
Yellow
Cyan
Black
Spot
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149. Screening An important parameter in offset printing is screening.
The screening frequency or halftone frequency is the resolution of a halftone.
It is the density of dots (how far they're spaced apart from each other) measured in lines per inch.
The screening frequency can be calculated using the following formula:
Engine resolution Screen ruling × = Amount of gradations
Examples:
engine resolution = 1200 dpi
screen ruling = 90 lpi
screen ruling = 150 lpi
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178 gradations
48 gradations

150. Screening Techniques The 2 most used screening methods are:
AM Screening:
Varying dot sizes, used by conventional presses
This type of screening produces good quality “flat tints”, however lacks the fine detail that can be produced by “FM” screening.
FM Screening:
Also called stochastic screening.
Uses small dots with fixed size, but with varying spaces between the dots.
This type of screen produces sharp detail, however it usually produces graininess in flat tint areas and is less responsive on press than “AM” screening in making slight color moves.
AM: Amplitude Modulation. – výhodný v plochých odstínech, nevýhodný při vykreslování detailů.
FM: Frequency Modulation. – větší zrnitost v plochých odstínech

151. Hybrid Screening
Hybrid screening is a mix of AM and FM screening, taking advantage of their pros while minimizing their cons.
Hybrid Screening is not a simple combination of screens, but a true hybrid of two screens.
The transition from one screen to the other screen occurs over a range of grey levels in such a way that it is not visible to the observer.
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152. Screen Angles
The screen angle is the angle at which the individual dots are printed.
A black and white halftone image consists of a single screen.
The screen pattern is very noticeable when positioned at 0° and is least visible when rotated 45° as illustrated below.
For that reason, black and white halftones are usually printed with 45° angled screens – particularly with coarser screens.
Úhel rasteru: raster je pro oči velmi patrný pokud je vykreslený v nulovém úhlu. 0°
45°

153. Moire
When two or more screens are printed on top of each another, a pattern known as moiré may appear.
The most serious moiré patterns occur at very small angles between screens.
The best angle between two screens that is least likely to cause moiré, and is most forgiving to small degrees of error, is 45°.
However, in four color process printing, four different screens must be superimposed and all four screens must be angled within the 90° limitation. 5°
10°
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154. 4 Colors
Based on theory and experience, a standard set of screen angles has been established for 4-color printing:
The least visible color, yellow, is placed at the most visible angle (0°, 90°).
The most visible color, black, is placed at the least visible angle (45°).
Cyan and magenta are placed in between them with angles of 15°/105° and 75°.
These angles represent a best all around compromise for most pictures and represent the standard, most commonly used screen angles.
They also form the least objectionable moiré – the rosette pattern.

155. CMYK and Spot CMYK and one ore more spot colors presents a problem.
Basically, you do not have any angles left for the spot color.
The basic rule is to use the screen angle of the least prominent (or missing) screened process color that will be underneath the screened spot color.
However, this not always possible.
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Cyan overprinted with PMS144 with yellow screen angle
Cyan overprinted with PMS144 with magenta screen angle
Cyan overprinted with yellow

156. Dot Shape
Another important parameter in offset printing is the dot shape.
The 3 most used shapes are elliptical, round and square.
Of these 3, the most common is the elliptical dot that gives smoother midtones, compared to the round and square dots.
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157. Dot Gain (1/2)
"Dot gain" is the term that is used to describe the difference between the requested tone value in the original application file and the resulting apparent final tone value on the substrate as measured with a densitometer.
On the next slide, you can see the alteration of halftone dots as they move through each stage of the offset printing process.
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158. Dot Gain (2/2)
When a tone value is requested, for example, in a page layout application
it becomes represented by a halftone dot pattern generated in prepress by the workflow RIP
which is then imaged onto a printing plate
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which is then inked
and transferred under pressure to the blanket
from which, again under pressure, the inked dots are transferred to paper

159. Countermeasure Dot Gain
Actually, there is no real countermeasure for dot gain, since it is simply a characteristic of a process that uses pressure to transfer an ink to a substrate.
The dot gain is highly dependent on the used machine, the used inks and the used substrate.
What operators do is simply measure the amount of dot gain for a given tone value.
Then, in the page layout software, they lower the requested tone value, so that the requested tone value + dot gain gives the wanted tone value.
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160. Back to Proofing
As you can see, in offset printing there are quit a few parameters involved.
Please note that the previous slides just showed a few.
In real life offset printing, there is a lot more to think about.
When you want to use a laser printer for proofing, the laser printer should be capable of mimicking most of these parameters.
Examples:
You may want to be able to change the screening to check for moiré artifacts.
You may want to be able to set dot gain to check what will happen with a given requested tone value.
Usually, this sort of things are only possible on professional color controllers like (Creo, Fiery).
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161. Proofing to a Standard
You can proof another device, by selecting the ICC output profile of the device, and use it as a simulation profile on a Creo or Fiery.
However, more and more popular is actually proofing to a standard.
A lot of printing companies have their devices (both offset and digital printers) certified for printing to a standard, for instance an ISO standard.
If the offset is certified for ISO Coated, just select the ISO Coated ICC profile as a simulation profile on the laser printer.
The next slide shows an example.
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162. Proofing Example
In this example, you can see a Fiery controller, setup for CMYK simulation of the ISO Coated standard.
The ISO Coated ICC profile is used as a simulation profile.
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163. Important Notes
If you want to use a laser printer as a proofing device, there are a few things to consider.
First of all, the proofing device must have a large gamut, since it needs to be able to print (almost) all the colors that the offset can print.
This can proof to be very difficult, especially when printing spot colors.
Another important note is that the proofing device needs to perform at its peak.
It needs to be regularly calibrated to maintain its output quality and it needs to be well maintained.
It needs an output profile for all media that is printed on.
This can be done through profiling.
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Peak –dobrá kondice zařízení.

164. 7. Profiling
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165. What is Profiling?
Profiling is the process of custom-made creating ICC profiles.
These profiles can, depending on their purpose, be used for simulation or as output profiles.
You can create profiles for other devices and use them as simulation profiles.
You can create profiles for your laser printer for different media types and use them as output profiles.
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166. Benefits of Profiling
Most professional controllers are shipped with some default output profiles for several media types (plain, gloss coated, matte coated).
However, since you do not know what media was used to create those profiles, and since these profiles were not created for your device, the default profiles may not give you the best results.
In most cases, the default profiles are created by profiling several machines, and then averaging the results.
The get the best out of your device, you should create the profiles on your media and for your device.
Note
The default profiles are not totally useless.
They can be useful if the print device provides a stable output, and when you use “standard” media.
Nevertheless, profiling is highly recommended for the best output.

167. Profiling in a Nutshell
Profiling basically consists of:
Printing patches on the device you want to proof (simulation profile) or on the proofer (output profile).
Measuring the patches with an photo spectrometer.
Convert the measurements into an output profile
Install the output profile on the printer controller of the proofer.
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Print combined calibration & profile patches
Measure Patches with ES1000 or
i1iO Scanning Table
Automatically install new profile on the Fiery
Use Profile Inspector to Accept Profile
Maintain Color by Calibrating at the Fiery

168. Profiling Software
To create profiles you will need software and hardware.
From the company X-Rite, for instance, you can buy the “X-Rite ProfileMaker 5 Platinum i1Pro Color Calibration System Bundle for Mac & Windows”, which contains software (Profile Maker 5 Pro) and hardware (i1 photo spectrometer).
With a price tag of nearly 2500 dollars, it is not exactly cheap, but quality comes at a price.
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169. Color Profiler Suite
The EFI Color Profiler Suite comes at a more reasonable price of around 1500 euro.
It includes the same i1 photo spectrometer, but then called ES-1000, and EFI-made profiling software.
It allows you to create printer profiles (for simulation and output), monitor profiles (crt, lcd) and device links, inspect and edit profiles and to measure control bars.
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170. Profiling Service
If you do not want to invest in profiling software, you can also find companies on the internet who offer a profiling service.
In most cases you will be asked to download some software and patch page(s) which you have to print on your color printer.
You send the printed page(s) back to this profiling company and they will create a profile for you.
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171. Profile Tweaking
Creating profiles for your machine and your media will not always produce the output you want.
The created profiles will accurately describe the behavior of the machine, but sometimes you may have to tweak the profiles a bit depending on your print job.
Think of printing a black cat with enough detail in de shadow areas or a polar bear with enough detail in the highlights.
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172. Profiling on WICE
If you want to know more about profiling, you can find a training module on WICE about the EFI Color Profiler Suite.
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Color Profiler Suite v2 on WICE, soon to be replaced with v3

173. Basic Color Management
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