ONYX ONYX. Color Management. Maintaining Consistent Color Communication and Profiles Benefits of Color Management Reproducibility Accuracy

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1 ONYX Color Management Maintaining Consistent Color Communication and Profiles Benefits of Color Management Reproducibility Accuracy ONYX ONYX Software Software for for Superior Superior Printing Printing Workflow Workflow Authorized Authorized Use Use Only Only All All Rights Rights Reserved

2 Why Color Management? Why do I care? Because everyone is talking about it Why do my customers care? Because they want accurate reproduction What impact will it have on my business? Helps reduce time and waste, controlling consumable Is it hard? NO!!! Is it absolutely needed? YES!!!

3 From Job to Job Today 2 Weeks Ago Some information provided by

4 From Print to Print Print #1 Print #10 Some information provided by

5 Color Management? What are users doing? Trial and Error Complaining to reseller or manufacture Nothing What should users be doing? Learn more about Color Management Calibration Use/Create (Correct) Profiles What are profiles? Description of a Device Input Profiles - source that created image (where it came from) Output Profiles - source that reproduces image (where it s going) Mode = Media, Ink, Resolution, Dot Pattern (MIRD) Use Media Manager to manage profiles

6 Color Quality Which image has the best color quality? Good color is whatever the customer is willing to pay for!!!

7 Communication Color How to Communicate Using a Connection Space How Profiles Work ONYX ONYX Software Software for for Superior Superior Printing Printing Workflow Workflow Authorized Authorized Use Use Only Only All All Rights Rights Reserved

8 How to Communicate Hebrew Chinese Navajo Russian French

9 Using a Connection Space Hebrew Chinese Navajo English Russian French

10 Profile To and From Connection Space Hebrew Chinese Navajo English Russian French

11 Profiles Communicate Color RGB Scanner RGB Monitor Profile Connection Space CMYK Printer A PhotoShop CMYK Printer B

12 Lost in Translation Original: I pledge allegiance to the Flag of the United States of America, and to the Republic for which it stands, one Nation under God, indivisible, with liberty and justice for all. English to Spanish to English: I promise loyalty to the flag of the United States of America, and to the republic for which it is stopped, a nation underneath a God, indivisible, with freedom and justice for all. English to German to English to Japanese to English: I the republic of sign of sign of American state and her to nation under the God to one, division non-stop loyalty promise possibly to freedom because of everything and justice.

13 How ICC Profiles Work A typical Color Management System (CMS) translates the image from the color source device to the Profile Connection Space (PCS). Then, in a second step, translates the image from the PCS to the color space of the destination device. Source Color Profile PCS Destination Color Profile The language each device speaks may be different, but the meaning is almost the same.

14 Device Dependent Source / Destination Profile RGB and CMYK are referred to as device-dependant color spaces because the colors defined are Intrinsically tied to the device it is defined on (e.g. printer, scanner, monitor). These color spaces cannot accurately be changed to any other device-dependant space without an interpreter.

15 Device Independent Profile Connection Space A color model not related to any device, but is instead based on human visual perception as defined by the CIE experiments begun in Contain all colors that may be perceived by the human eye. Used to convert from one device-dependent color space to another device-dependent color space. i.e. Within the L*a*b* Color Space an input RGB image is convert to a CMYK output.

16 L*a*b* The L*a*b* space is a fixed standard, so any defined value will ALWAYS be accurate. The three components are: L* - lightness Ranges from 0 (no lightness=black) to 100 (maximum lightness=white) a* - red-to-green value Ranges from +128 red to -128 green b* - yellow-to-blue value Ranges from +128 yellow to -128 blue

17 ICC Color Profiles Accurately maps a specific device-dependant color space to the L*a*b* standard. Maps L*a*b* values to a device-dependent space. If an initial colorspace is RGB, then an ICC profile defines the RGB data in terms of the L*a*b* color space. Profiles can contain their own gamut mapping used during this conversion. An output profile accurately maps the L*a*b* values to a CMYK colorspace for the image to be printed.

18 Input Profiles Must be Accurate Starting Color Starting Color Correct input profile same output printer profile Incorrect input profile Correct Color Output Incorrect Color Output

19 Controlling Variables How to profile your devices Scanners Monitors Printers ONYX ONYX Software Software for for Superior Superior Printing Printing Workflow Workflow Authorized Authorized Use Use Only Only All All Rights Rights Reserved

20 Profiling Your Scanner 1. Scan a target swatch 2. Measure patch values 3. Build ICC profile When you scan images make sure this profile is applied or embedded within the file. Variables: - scanner quality - settings in the scanner software - quality of scanner target

21 Profiling Your Monitor 1. Configure monitor settings 2. Measure colors produced by monitor 3. Build ICC profile Although having a soft proof on your monitor that is similar to the printed output, remember that your monitor is RGB and your printer is CMYK. Variables: - monitor settings (brightness, contrast, etc ) - duration of use of the monitor - ambient light Monitors also shift consistently, so keeping them calibrated should be routine maintenance.

22 Profiling Your Printer Modes You don t just profile your printer. You profile print modes. Printer Variables Include: Printer technology Ink Media Heat and dryer temperatures RIP Variables Include: Dot patterns Resolutions Ink densities Environment Variables Include: Lighting Humidity Etc..

23 Printer Calibration Matching printer output to software calibration tables Once you have defined the media and mode settings, you must calibrate the device Print a control swatch and measure the patches with densitometer or similar device This produces a baseline table for ink values that can easily be re-calibrated without affecting your ICC profile Deals only with previously selected target ink densities and current printer output capabilities

24 Print ICC Swatch Defines color gamut of output device The more patches you use the more accurate the profile will be Prints with calibration applied Most accurate if read right after curing When you read the swatch you ll see expected and achieved colors and the L*a*b* or spectral values

25 Configure Profile After measurment, define the ICC build options to determine the output profile settings. The output profile settings determine: How to render colors inside/outside the profile gamut What to do with colors on the boundary of the gamut What inks to use for gray balance (GCR or UCR) Total Ink Limits within the ICC See - ICC Build Options for details

26 Importance of Adding K GCR - Grey Component Removal 75% 50% 150% 100% 25% C 75% M 50% Y 25% K 50% M 25% Y 25% Black ink gives increase contrast and tone. CMY alone creates a muddy brown, not a true black. A CMYgray scale is extremely vulnerable to light changes. Black is also added to reduce the amount of ink used.

27 GCR vs. UCR GCR Grey Component Removal This method of black generation replaces a certain percentage of CMY with the equivalent amount of K. UCR Under Color Removal This method of black generation that uses black only in the neutral and gray areas. This is theoretically the opposite of GCR. Too much K ink can result in peppering effect (coarseness) Moderate or Medium usually produces best results and smoothness No K ink can cause image flatness and unstable gray balance Using GCR you can maintain smoothness while using less ink Using UCR you can maintain neutral grey while sacrificing smoothness in the highlight areas

28 GCR vs. UCR GCR Grey Component Removal CMY K UCR Under Color Removal K CMY Start Point Smoother Highlights More unstable gray balance Traditional black method Start = 50 65% Start Point Coarser Highlights More stable gray balance Better contrast and tonality Start = 30-40%

29 Workflow Color Management in ONYX QuickSet Color Management Rendering Intents Benefits of Color Management ONYX ONYX Software Software for for Superior Superior Printing Printing Workflow Workflow Authorized Authorized Use Use Only Only All All Rights Rights Reserved

30 Color Management in ONYX Working with Profiles Print using media profiles defined in the QuickSet Apply within Preflight or Layout modules Media (material) and Modes (dot pattern and resolution) Installing and Downloading.PrnInst files or.oml from disc or web Managing, Applying and Editing Use the Printer > Change menu within RIP-Queue to match jobs In Media Manager > Edit a Profile In Media Manager > View Media Library (Edit or Rename) Importing, Exporting, and Backing-up Import/Export using RIP-Queue Printer Configuration> Media Tab Import/Export using Media Manger Library

31 QuickSet Color Management Change Profile Settings Within ONYX all color management dialogs include these same tabs Profiles Tab Input source file Embedded Profiles Rendering Intents Tab See - Color Theory for definitions Output Tab Device Profiles (Default ICC)

32 Color Management Workflow Scanners, PhotoShop, Quark, Etc.. Every gamut transform uses a Rendering Intent Screen Preview Final Print Reconcile the difference between the input and output profile using different rules Different Intents have different outcomes in terms of how this reconciliation is computed Postscript files that have bitmap & vector data can have different assigned intents to each type of data Proof Printer

33 Rendering Intents within ONYX The setting that tells the color management system how to handle the issue of converting colors between color spaces when going from a larger gamut to a smaller one. The method used for mapping colors from one device's gamut to that of another. Rendering intent is specified for different types of applications (data/images). The ICC specifics four rendering intents. Perceptual Photos and images Relative Colorimetric Color matching and proofing Absolute Colorimetric Color matching and proofing Saturation Vector graphics PosterColor (ONYX Proprietary) Vector graphics Maps gamut of input profiles directly to gamut of output profiles, by passing any gamut mapping done prior to L*a*b* conversion. Maintains saturation for example with pure hues as seen in the input color gamut space.

34 CRDs: : Perceptual This intent is best for photographic images. The relationship between colors in original is scaled proportionally to fit the output device s color gamut.

35 CRDs: : Relative Colorimetric Is best for images, such as logos, where the original needs to exactly match the output. Colors that falls outside of printer s gamut are converted to the edge of the gamut, which may reduce the total numbers of colors available (Gamut Compression). This intent should be used when there are relatively few colors in an image

36 CRDs: : Absolute Colorimetric This intent is based on the Relative Colorimetric intent and is best when trying precisely match a logo color. However, this intent simulates the media white measurement within the output ICC profile and will print to simulate it.

37 CRDs: : Saturation This intent is best for images where true color matching is NOT as important as vivid colors. This intent may be used to boost colors within a photographic image.

38 Rendering Intents Perceptual tries to preserve the perceptual relationships in an image, even if this means remapping all colors both in-gamut and out-of-gamut. This is usually the preferred rendering intent for images that contain many out of gamut colors, but if all colors are ingamut for the target color space, relative colorimetric may be preferred. Relative Colorimetric maps to an exact match wherever possible, and where not possible (because the color is out of gamut of the target gamut), the color is mapped to its nearest equivalent. In most cases, this conversion should include a remapping of the white point so that this colorimetric match is relative to the target white point. Absolute Colorimetric maps to an exact match wherever possible, and where not possible (because the color is out of gamut of the target gamut), the color is mapped to its nearest equivalent. In certain stages of proofing, this conversion of a colorimetric match should be absolute. The colors should be converted as if the match were being done relative to the source device s white point, for example the white point within the image. Saturation tries to preserve the saturation properties of colors as much as possible, even at the expense of hue accuracy or perceptual relationships. This is usually, but not always, the preferred rendering intent for information graphics where it s desirable to maintain saturated vivid colors.

39 Pleasing Rendering Intents Accurate Pleasing Perceptual: The full gamut of the image is compressed or expanded to fill the e gamut of the output target. Gray balance is preserved, but colorimetric accuracy might not be. b Every CMM performs this differently! Good for rendering images and photographs. Saturation: The saturation of the pixels in the image is preserved, at the expense e of accuracy in hue and lightness. Used for rendering business graphics.

40 Accurate Rendering Intents Accurate Pleasing Relative Colorimetric Colors are mapped as accurately as possible but using the white point of the output media Used for color matching Absolute Colorimetric Colors are rendered as accurately as possible and the white point using the white-point of the input (reference) profile Used for color proofing because it simulates media

41 PosterColor Color Rendering Typical Solvent or Pigmented Ink Output Same CMYK file with PosterColor rendering Exclusive ONYX technology used for CMYK POP signage, not photos Maintains grey-balance and hue matching Truly takes advantage of full gamut of ink so every print has eye-popping color

42 Benefits of Color Management Allows non-specialists to take advantage of specialist s knowledge Provides easy communication of color with customers Improves overall color consistency Makes proofing simple and reliable Enables different devices, ink and media to reproduce similar colors Reduces print provider s spoilage of consumables Reduces everyone s frustration with color Helps satisfy the print buyer s color demands

43 Without Color Management Same ink, 100% amount of Cyan: Media A Media B Media C Media D Media E Media F Media G Same media, 100% amount of Cyan: Ink A Ink B Ink C Ink D Ink E Ink F Ink G Every printer, ink and media combination produces different color or Remember RGB and CMYK are not standards

44 With Color Management CMS decides ink values: Media A Media B Media C Media D Media E Media F Media G Same media, CMS decides ink values: Ink A Ink B Ink C Ink D Ink E Ink F Ink G CMS tries to make output consistent and predictable Input Profile and Rendering Intent have biggest affects

45 Questions

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