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Xerox Document Services 
Platform

Color Management Guide

701P40210
Version 3.7
May, 2003

Summary of Contents for 6180N - Phaser Color Laser Printer

Page 1: ...Xerox Document Services Platform Color Management Guide 701P40210 Version 3 7 May 2003 ...

Page 2: ...rope and XEROX Canada Limited The Document Company the stylized X and all names identifying numbers used in connection with Xerox products mentioned in this publication are trademarks of XEROX CORPORATION All non Xerox brands and product names are trademarks or registered trademarks of their respective companies Other company trademarks are also acknowledged This product includes software develope...

Page 3: ...Native path 2 5 Fast Reprint path 2 5 PANTONE path 2 5 Color Manager 2 6 Associations 2 6 Calibration 2 6 New Stock 2 6 Assign profile 2 6 New color group stock group 2 6 Color profiles 2 7 User TRCs 2 7 Color tools 2 7 Print engine specific mode 2 7 Xerox consistent color mode 2 9 Custom color mode default 2 10 Color adjustments 2 10 Image quality tools 2 10 Expert color 2 11 Print as grayscale 2...

Page 4: ...tup 3 7 Three Stock Model Setup 3 8 Custom and Colored Stock hints 3 11 4 Using color tools 4 1 Using Custom color mode default 4 1 Basic color tools 4 2 Image quality tools 4 3 User Tonal Reproduction Curves TRCs 4 4 Expert color tools 4 5 Spot Color Editor 4 10 Understanding the Spot Color Editor window 4 10 Open PrePress Interface OPI 4 11 Using Print Engine Specific mode 4 13 Using XCC Xerox C...

Page 5: ... that the DocuSP operator is familiar with the DocuSP controller and the attached print engine and is also familiar with color printing Refer to the DocuSP on line help system for procedures on how to use the DocuSP color tools Multiple print engines The DocuSP controller includes color management tools for the DocuColor 2045 2060 6060 and iGen3 Digital Production Presses This guide provides gener...

Page 6: ... Directory paths for example Browse to the Color profiles directory Text that you enter for example Enter purple or Xerox Calling attention to text that is particularly important for example Select Stop on the user interface window Do not press the red stop button on the controller Introductory words or phrases that begin items in a list for example Hold job The document is held at the printer Can...

Page 7: ...ion Color Management Guide 1 3 Customer Support For service and software support dial 1 800 821 2797 This number is enabled for TTY bridges To reach Xerox Documentation and Software Services dial 1 800 327 9753 ...

Page 8: ...Introduction 1 4 Color Management Guide ...

Page 9: ...halftone Color management software converts RGB and CMYK input color profiles to the color gamut of a specific output device DocuSP supports the traditional CMYK workflow as well as the ICC Profile workflow TRCs and other color tools allow you to make custom color adjustments fine tuning the color image DocuSP provides the software color management tools you can use to produce quality color output...

Page 10: ...s made by you the user Color path charts Jobs take one of five paths through the DocuSP controller Whenever possible you should use the Xerox Enhanced Path which provides the highest quality color for incoming SWOP CMYK color and faster RIP speed The color path chart see Figure 2 1 Simplified DocuSP Color Workflow displays the paths different documents take as they move through the DocuSP color ma...

Page 11: ...s the color is transformed from Input such as RGB or input CMYK to Profile Connection Space PCS to output CMYK or SWOP CMYK The K channel will not be preserved for incoming CMYK data The chief benefit of using this path is its ease of use The following conditions guarantee a job follows the ICC standard path A user output profile has been assigned to the job A color adjustment lightness contrast s...

Page 12: ...nstead of first being translated to device independent space and then to the print engine specific space RGB data is converted using 3 x 4 LUTs 4 x 4 LUTs provide direct CMYK to CMYK mapping preserving black When pure black is passed through a source profile ICC profile path it is converted to XYZ Once in XYZ there is no way for the color management system to know that the color was originally pur...

Page 13: ...engine Fast Reprint path Fast Reprint jobs accessed through Reprint Manager are saved using Print and Save or Save commands when processing the job Fast Reprint jobs do not require re RIPping Color management properties are set prior to saving the job The only color change that can be applied to a job on the Fast Reprint path is a User TRC Benefits of using this path include No need to re submit j...

Page 14: ...k or color group For more in depth information regarding calibration see chapter 3 New Stock Destination color profiles are required for each stock or color group Stocks added from the catalog Xerox Qualified Stocks will automatically be placed in the proper color group New custom stocks will automatically be placed in the default color group Assign profile Each stock is automatically assigned to ...

Page 15: ...s User Tone Reproduction Curves TRCs provide the skilled user with a tool for adjusting the individual CMYK color separations in an image and saving those adjustments for use on other images The User TRCs tab provides a list of user created TRCs and allows you to create new TRCs Color tools Color tools allow you to make adjustments that impact the color characteristics of a print job Color tools c...

Page 16: ...k System Specified pre installed and optimized for the iGen3 Lightness 0 Contrast 0 Saturation 0 Color Cast all 0 TRCs None Press Color Emulation None Table 2 2 DocuColor 2045 2060 6060 mode default property settings Queue Property Queue Setting Rendering Intent Relative Colorimetric RGB Source sRGB CMYK Source SWOP CMY Source Gray Source System Specified Destination ICC Profile Front Back System ...

Page 17: ... None Press Color Emulation None Table 2 2 DocuColor 2045 2060 6060 mode default property settings Queue Property Queue Setting Table 2 3 XCC mode default and override settings Queue Property Queue Setting Applicability Rendering Intent Images Relative Colorimetric Default Rendering Intent Text Pure Default Rendering Intent Graphics Saturation Default RGB Source XCC Mode RGB Default CMYK Source SW...

Page 18: ... to make adjustments in color images Lightness controls the relative brightness or darkness of the color image Contrast is the ratio between the light tones and dark tones in an image Saturation controls the strength or purity of the color image Color Cast adjustments provide you with the ability to increase or decrease the amount of a single color in an image User TRCs are created to provide a co...

Page 19: ... the color transformation from the device independent space to the print engine CMYK space Halftones are screen patterns achieved by printing dots or lines in a specific pattern The distance between the dots is fixed Dot size varies in accordance to the strength of the color The darker the color the larger the dot Halftones supported on the iGen3 include 150 dot 175 dot 200 dot and stochastic scre...

Page 20: ...ring intent provides color mapping options The available rendering intents are covered in detail in Chapter 4 Using Color Tools and are as follows Saturation Perceptual Relative Colorimetric Absolute Colorimetric Pure Print as grayscale Print as grayscale converts color content to gray Refer to on line help for the details as well as for information on billing Spot color editor DocuSP has a built ...

Page 21: ...igh resolution images at RIP time This speeds up job submission time because you can submit a job with the low resolution images much faster than with high resolution images OPI is covered in more detail in Chapter 4 Using Color Tools DRIs Display Resolution Images The option exists in the Job Properties tab to save the DRIs embedded in a job This must be enabled to allow viewing and editing withi...

Page 22: ...DocuSP color management 2 14 Color Management Guide ...

Page 23: ...tone for printing you need not calibrate it Once a stock is calibrated DocuSP saves that calibration and automatically selects the latest calibration for the stock when the stock is required by a job DocuSP can save up to five calibrations per stock These saved calibrations are assigned to the color group in which the stock resides for use with any stock within that color group Characterization Ch...

Page 24: ...roups cannot be deleted Xerox Qualified Stocks may be removed from your Stock Library but not from the Stock Catalog However you may add new non Xerox stocks to the existing stock groups It is advantageous to do so as long as the new stocks share the same white point value Additionally it is suggested that you place any colored stocks you wish to use in the Other group although perfectly fine resu...

Page 25: ...ocess overview Refer to the on line help for a detailed calibration procedure Prior to initiating the calibration process the stock you plan to use for calibration needs to be in a paper tray and that tray programmed for that stock Begin by calibrating the DTP41 X Rite Spectrophotometer NOTE Calibrating the Spectrophotometer needs only be done once a day You need the reflective strip card that has...

Page 26: ... calibrations are assigned to Stock A with a 175 dot halftone and Stock A with a 200 dot halftone When calibrating 8 5 x 11 A4 stock print 40 single sided copies of the 2 page target For larger sized stock print 20 single sided copies of the target we recommend using the final print for calibration Calibration target tips DocuSP calibration software checks the first color at the top of each calibr...

Page 27: ...nagement Guide 3 5 This procedure is more likely to be necessary for iGen3 due to image to page registration errors but may also be applicable for DC20xx 60xx printers Figure 3 1 Calibration target and whitespace Figure 3 2 Calibration step 1 ...

Page 28: ...Stock Management and Calibration 3 6 Color Management Guide Figure 3 3 Calibration step 2 Figure 3 4 Calibration step 3 ...

Page 29: ...Unspecified Stock Name model This workflow is best for customers that have a limited number of stocks and want very consistent color outcomes with very easy system operation Key Points to this approach One calibration event covers all of the stocks at a site You accept the default characteristics for all stocks Therefore stocks with slightly different whiteness Bright White White and Non White wil...

Page 30: ...trays with physical stock attributes selected and name remaining Unspecified Calibrate ANY stock named Unspecified In Printer Manager Paper Trays right click on any tray stock and select calibration Perform the calibration process You have now calibrated and loaded all stocks and trays on the system Any incoming job that matches an attribute of the stock such as the size pulls from the appropriate...

Page 31: ...ck and add the stock from the Stock Catalog to the Stock Library 3 Select your stock in Printer Manager and calibrate if required NOTE The pre installed stocks have 1 of 3 stock profiles Bright White White or Other based on their color group Adding New Stock Non Xerox 1 Select Printer Manager New Stock 2 Add your custom name 3 Select the color group if a group other than the default group is desir...

Page 32: ...6 3r11390 163 97 1 Color Expressions 96 3r11385 105 97 0 Color Expressions 96 3r11387 120 97 0 Color Expressions 96 3r11380 90 96 8 White Digital Color Colotech SuperGloss 3r95451 135 95 0 93 7 L 95 Digital Color Super Gloss 3r6290 8pt 94 8 Digital Color Super Gloss 3r6294 10pt 94 7 Digital Color Super Gloss 3r6350 12pt 94 4 Digital Color Colotech Silk Coated 3r97166 120 94 3 Digital Color Gloss C...

Page 33: ...tion to force feed from the tray Alternatively you can just program a specific stock for your job NOTE The option to force feed from a tray is not available on the iGen3 3 Submit a job to a hold queue on the controller The job should contain a variety of image types i e photos halftones and graphics as well as text You should be familiar with how this job prints on white coated or uncoated stock 4...

Page 34: ... profile each time NOTE After the job proofs it will appear in the inactive jobs list of the Job Manager and will be designated as successfully proofed This is where you will find it the second and third time you proof it 12 Compare the three prints By determining which of the destination profiles produces the most pleasing prints on your colored media you can decide to which color group you shoul...

Page 35: ...ine calibration and easy to use color tools to adjust color cast using simple slider bars for lightness contrast and saturation Trapping Black Overprint and anti aliasing can also be applied Expert Color Management provides high quality consistent color with routine calibration and provides you with a full compliment of industry standard color management tools for making color adjustments Using Cu...

Page 36: ...nt is made on an image The adjustments are made during the RIP creating the DocuSP CMYK output profile Basic color tools are used when an image requires a global adjustment that can be made by one of the tools Use Lightness to lighten or darken an image Increase Contrast to lighten highlights and darken shadows Decrease Contrast to darken highlights and lighten shadows Increase Saturation when you...

Page 37: ...owards Magenta adds magenta by reducing green Moving the slider bar towards green adds green by reducing magenta Yellow vs Blue moving the slider bar towards yellow adds yellow by reducing blue Moving the slider bar towards blue adds blue by reducing yellow Image quality tools Image quality tools can be applied at the queue job or page level Figure 4 3 Image Quality Tools Trapping compensates for ...

Page 38: ... of white around the black object To view the dialog in which to find and set this feature see Figure 4 3 DocuColor iGen3 lays the colors onto the image in a unique manner with black being laid down first Using black overprint causes muddy looking blacks The default setting for Black Overprint on the iGen3 is off and it is recommended that you only use this feature when you must Anti aliasing redu...

Page 39: ...nt could be created and applied to every job submitted from that device This saves job preparation time and assures that the same adjustment is made to all jobs submitted from that device Expert color tools Skilled users employ expert color tools for high level color adjustments Users select source and destination color profiles to be used in conversion to engine CMYK Usage of the expert color too...

Page 40: ...d 200 for coated stock jobs For DC 20xx 60xx we suggest you use the default profile Image Resample The DocuSP controller provides you with the ability to select an interpolation or image resample method to scale images for output in order to achieve maximum Image Quality at the desired RIP performance Interpolation is defined as the process of estimating a value of a function between two known val...

Page 41: ...ller Bi Linear Interpolation A method used to scale image data pixels from one resolution to another The replacement pixel in the scaled image is calculated using a weighted sum of the four nearest pixel values in the source image This method offers higher quality than Nearest Neighbor Interpolation Smart Interpolation A method used to scale image data pixels from one resolution to another This in...

Page 42: ...ting includes profiles for assigning Gray Component Removal GCR GCR is a process for replacing an equal percentage of gray with black reducing the amount of dry ink used You can select a GCR profile for most stocks However it is often best to use the System Specified setting which is optimized for your system Use destination profiles to override the color profile assigned by a stock s color group ...

Page 43: ...st color values in the print engine color profile to the input profile taking into consideration the white point of the media Used for color matching such as matching a SWOP proof Use Absolute Colorimetric when attempting to apply the closest color values in the print engine color profile to the input profile using a standard white point Absolute Colorimetric is used for comparing to an absolute v...

Page 44: ... and delete custom colors You can print a swatch book of PANTONE Uncoated or PANTONE Coated colors or print a proof of a color being edited Understanding the Spot Color Editor window The Spot Color Editor contains several menus as well as lists that enable you to view spot color properties and edit spot colors Figure 4 8 The Spot Color Editor tab The View menu The View menu is a drop box that enab...

Page 45: ...to print out a full book of PANTONE color swatches Revert Available when an edited PANTONE color is selected this control reverts an edited color back to its original settings Delete Available when a custom color is selected this control displays the Delete Confirmation Alert box Redisplay refreshes the view in the Spot Color Editor Color Name A text field that can be used to find a specific color...

Page 46: ... image 3 A queue is set up with OPI Substitution enabled This feature is found in the Queue Properties PostScript PDF tab 4 A low resolution image is created as an analogue to each full resolution image these are distributed to the document creators 5 The document creators position the images in their documents and include placement sizing and cropping information as well as OPI comments these are...

Page 47: ...fic mode provides pre defined settings that optimize the performance of specific DocuSP based print engines This mode provides a consistent profile conversion path for undefined profiles providing the best default color interpretation and rendering values for the print engine The print engine default settings are applied if there is no corresponding property set within the job The Print Engine Spe...

Page 48: ... it is submitted to any Xerox color print engine running in XCC mode XCC standardizes the way the DocuSP controller interprets unknown input color profiles and standardizes the conversion through a Xerox standard output profile When XCC is selected you cannot make any other color adjustments The color properties are grayed out and not selectable Many of the jobs that use XCC are saved in Fast Repr...

Page 49: ...e solved at the DocuSP or does it need to escalated This troubleshooting module assumes that actions can be taken at the DocuSP to solve the problem Image paths A good place to start troubleshooting is to identify the image path the job took through the system Determine whether the job took the Xerox Enhanced Standard Fast Reprint or Native path and submit the job using another path If the job suc...

Page 50: ... remember Color Adjustments are performed in PCS XYZ thus always invoking the ICC path Calibration and User TRCs are applied in hardware They do not affect RIP performance or color pathway The Xerox Enhanced Path always provides improved RIP performance and better image quality Using pre installed profiles and Look Up Tables is sufficient for most customer jobs and most stock Building and utilizin...

Page 51: ...Magenta vs Green Yellow vs Blue 0 100 all Cyan vs all Red 0 100 all Magenta vs all Green 0 100 all Yellow vs all Blue 0 100 all Cyan vs all Red 0 100 all Magenta vs all Green 0 100 all Yellow vs all Blue Trapping Off When enabled height 1 width 1 Off When enabled height 1 width 1 Image Graphic Trapping Off Off Black Overprint Off Off Anti Aliasing Off Off Source Color RGB sRGB CMYK SWOP Coated CMY...

Page 52: ...r Smart Destination Profile System Specified System Specified Emulation Off Off Rendering Intent Saturation Perceptual Relative Colori metric Absolute Colori metric Pure Images Relative Colorimetric Text Pure Graphics Saturation Images Relative Colorimetric Text Pure Graphics Saturation OPI Off Off Table A 1 Color Management tool DC 2045 2060 6060 DC iGen3 ...

Page 53: ...clairage an international standards committee L A B is a color space that describes color in terms of human eye response CMYK A color space model that defines the relative amounts of Cyan Magenta Yellow and Black toner or ink that will be applied to the print CMYK can be found in both input and output profiles Coated Coated refers to whether the stock in use has been coated or was left uncoated Ge...

Page 54: ...B color space The jpg files in a print job will need to be converted to CMYK prior to printing Lightness The perceived reflectance of a surface Matte Matte refers to an attribute of a stock which is a flat color with no glossiness Matte stocks tend to appear halfway between uncoated stock and coated stock OPI Open PrePress Interface the process of substituting full resolution images residing in a ...

Page 55: ... B and the R is a saturated Red Source Profile The color profile with which the job was created at the client workstation prior to submission It is often embedded as part of the PDL but if not embedded a source profile can be assigned by the DocuSP controller at the job or queue level Spectro photometer A tool which measures the quality of the printed test pattern and enables calibration of the pr...

Page 56: ...nt basis User TRCs can be applied to all jobs including those that originate as Reprint files Uncoated Uncoated defines whether a stock has been coated or was left uncoated Generally prints on uncoated stock will appear flatter than do prints on coated stocks XYZ A color space which maps to human eye response The DocuSP controller utilizes XYZ as its Profile Connection Space PCS ...

Page 57: ... family 3 4 DC iGen3 3 4 Characterization 3 1 CMYK Native path 2 5 Color manager 2 6 Color paths 2 2 Color profiles 2 7 Color Tools using 4 1 Colored Stock hints 3 11 Custom color mode 2 10 Color Tools 2 10 Expert Color 2 11 Image Quality tools 2 10 using 4 1 D Destination Profiles 2 12 4 8 DocuSP workflow chart 2 3 DRIs Display Resolution Images 2 13 E Emulation 2 12 4 8 Expert color tools 4 5 ...

Page 58: ...rface OPI 2 13 P PANTONE path 2 5 Print engine specific mode 2 7 4 13 Q Queue Overrides 2 1 R Rendering 4 8 Rendering intent 2 12 Absolute Colorimetric 4 9 Perceptual 4 9 Pure 4 9 Relative Colorimetric 4 9 Saturation 4 9 S Smart Interpolation 4 7 Spectrophotometer 2 1 Spot color editor 2 12 using 4 10 Stock Management hints and tips 3 7 Stock Workflow setups 3 7 T Three Stock Model setup 3 8 ...

Page 59: ...Troubleshooting 5 1 U Unspecified Stock Name Model setup 3 7 User TRCs 2 7 4 4 X XCC mode using 4 13 Xerox consistent color mode 2 9 Xerox Qualified Stocks tips for use 3 3 ...

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