relinearization and profiling tutorials · 2012-10-08 · relinearization and profiling tutorials...

Relinearization and Profiling Tutorials

ColorBurst RIP 9

SpectralVision Pro v.2.6

© 2004-2009 CSE, Inc.

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Table of Contents

Relinearization tutorial

1 Introduction to Linearization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2 The Relinearization Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3 Linearization Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Profiling tutorial

4 Introduction to ICC Profiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5 The ICC Profiling Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

6 Technical Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25


Introduction to Linearization

How can you guarantee that today’s prints match the ones you did last week? There are many variables to consider—over time (and on every different media) a printer will drift from its original state. Printers, paper, and inksets all have slight variances in manufacturing consistency. Altitude, age of printer, and humidity can come into play causing one printer not to match another even if they have the same model number, inkset, and paper.

The answer is linearization. A linearization file is a curve that corrects for non-linear output throughout the tonal scale, and is an integral part of each ColorBurst environment. Relinearizing a ColorBurst environment allows ColorBurst to account for these differences and adjust accordingly, ensuring consistent output from your printer over time. This puts the printer back into its original state, reproducing all the conditions under which the ICC Profile was made. When you relinearize, you have made the ICC profile as accurate as the day it was made.

overview of the Relinearization Process

a) Print a linearization target through ColorBurst.

b) Use SpectralVision Pro and a spectrophotometer to measure the target.

c) Save the measurements as a lin file in SpectralVision Pro.

d) Load the lin file in ColorBurst. ColorBurst adjusts the new lin file values to meet the baseline values that were originally set in your ColorBurst environment.

e) Verify your lin readings in ColorBurst. The densities in the new lin file should fall within 0.0–0.3 of the baseline values. If the values are not in spec, they can be adjusted by modifying the ink densities.

f) Save the environment to include the new lin file as part of the environment.

note Relinearization does not involve changing the Baseline densities—this is only done when a new ICC Profile is made.

1


SpectralVision Pro Installation

SpectralVision Pro is installed as part of the ColorBurst installation. The SpectralVision Pro program can be launched using the SpectralVision Pro shortcut on your desktop (created during installation), by clicking the Launch SpectralVision Pro button in the SpectralVision Pro tab of the Linearization dialog, or by going to the ColorBurst\Profiling Tools & Docs\SpectralVision Pro folder. The latest version of SpectralVision Pro is also available for down-load on the ColorBurst web site, www.colorburstrip.com.

SpectralVision Pro is available for both the Windows and Mac OS X platforms. The SpectralVision Pro interface and profiling technology are identical on both platforms.

Spectrophotometer Support and drivers

The following X-Rite devices are supported for relinearization in SpectralVision Pro.

DTP20 (PULSE) Eye-One

DTP22 Eye-One iO

DTP41/DTP41T Eye-One iSis

DTP45 Eye-One iSis XL

DTP530 iCColor

DTP70 SpectroScan

DTP938 SP62

DTP939

Device drivers for spectrophotometers are located in the ColorBurst\Profiling Tools & Docs folder. When connecting your device for the first time, use the New Hardware Found dialog to select the driver from the ColorBurst\Profiling Tools & Docs folder.

NOTE If you have already installed your spectrophotometer software or drivers you will not need to use the drivers in the ColorBurst\Profiling Tools & Docs folder.


The Relinearization Process

IMPoRtant When relinearizing a ColorBurst environment, a UV-filtered spectrophotometer is recommended. Using non–UV-filtered devices may lead to undesirable results.

1. Perform a nozzle check on your printer. Use the front panel on your printer to perform a nozzle check. Verify that there are no missing jets. Correct as needed.

2. Print the linearization target through ColorBurst.In ColorBurst, do the following:

a. Use the Environment menu to choose the environment you want to relinearize. Make sure the matching media is loaded in your printer.

Figure2.1.Load the environment you want to relinearize from the Environment menu.

b. Make sure your printer settings are correct and your printer is ready to print.

c. Open the Linearization Options dialog. In the Lin and Profile Targets tab, select your device from the list. Click the Print target button. A message will appear stating that the target was sent to the Job List. Click OK to continue.

2


Figure2.2.Select a Lin Target and click the Print Lin Target button to send the lin target to the Job List with instruc-tions to print without color management.

When you click the Print Lin Target button, the target is sent to the Job List with instructions to print the file with all color management off (only the CMYK Color Adjustment limits are in use). These files are indicated by bold italic text in the Job List. This allows you to print the target in a raw (unmanaged) state. The target can be dragged back into the Job List to reprint without color management, as long as the name is shown in bold italic text.

Figure2.3.The Lin target listed in bold italic text will print with color management off.

note The Custom target option allows you to select any file to send to the Job List with instructions to print with color management off.

d. Once the Lin target file is placed in the Job List, make sure the file status is Ready, the lin target is at the top of the Job List, and the RIP is On to print the target file.


Figure2.4.Print a Lin target that has been formatted for your spectrophotometer. You may need to trim the target to fit your device.

note Do not scale the linearization target. Always print it at 100% of the original size.

�. launch SpectralVision Pro.There are three ways to open SpectralVision Pro:

• double-click the SpectralVision Pro shortcut on the desktop;

• click the Launch SpectralVision Pro button in the SpectralVision Pro tab of the Linearization dialog; or

• launch SpectralVision Pro from the ColorBurst\Profiling Tools & Docs\SpectralVision Pro folder.

note Be sure to only run one instance of SpectralVision Pro.

Figure2.5.Launch SpectralVision Pro to measure the Lin target.

�. Select your target and connect to your device.a. In SpectralVision Pro, make sure you are in the Measure Target tab.

b. In the Target pop-up, select the Lin target for your device.


c. The Measurement Device field will automatically select the spectrophotometer associated with the target you have chosen. If your device uses a serial connection, select the correct port in the Serial Port pop-up.

d. Click the Connect button to connect to your device.

noteS When you click the Connect button, a Device Info dialog appears with settings specific to your device. This dialog can also be accessed clicking the Info button (“i”) next to the Measurement Device pop-up menu. The DTP41-45 has 4 device options. Switch to the device version that matches your equipment prior to connecting.

e. If your device has an option for UV filtering, make sure the correct UV filter option is selected.

note Do not close this window when using the iSis device.

�. Measure the lin target.Use your device to measure the Lin target. (See your device’s documentation for operation instructions.) As the values are read, the patches will be displayed in SpectralVision Pro, and the Measurement Status bar will show the measurement progress. If you encounter an error reading the patches, you can click the Clear Data button to start over.

6. Save your linearization file.After all of the patches have been read, save the measurements as a Lin file by clicking the Save button. It is recommended to save your Lin file in the ColorBurst\Lin folder, but it can be saved to any location.

note For easy reference, include the following settings in your lin file name: media name, print resolution, Bi-D/Uni-D, number of print passes, and date.

�. load your lin file in ColorBurst.In ColorBurst, do the following:

a. Open the Linearization Options dialog (Options > Linearization Options).

b. Click the Select a lin file button. Locate the Lin file you saved in step 6, and click the Open button. This loads the measurements from the target into ColorBurst as the Actual CMYK values.

Figure2.6.Use the Select a lin file button to load your new lin file.

�. Verify the new lin values.The Actual values from the new lin file should be within 0.0–0.3 density above the Baseline densities saved in the environment.


When relinearization values are too low:If any of the Actual values from the new lin file are lower than the Baseline values saved in the environment, an error message will be displayed indicating that the Linearization will fail. In this case, please refer to Section 3: Linearization Troubleshooting in this document.

Figure2.7.An error message will indicate low lin values in bold.

When relinearization values are too high:If any of the Actual values from the new lin file are more than 0.3 above the Baseline values saved in the environment, you will not get an error message, but the color in your prints could be off due to the linearization having to correct for such a large difference. Please see Section 3: Linearization Troubleshooting in this document.

note Do not change the Baseline densities when relinearizing. By relinearizing you are calibrating your printer to an existing baseline, not creating a new one. The Baseline densities in the Advanced Linearization settings are only used if you are building a new ICC profile.

9. Save your ColorBurst environment.If your new lin file Actual values are within 0.0–0.3 of the environment’s Baseline values, you can save the environment at this point to lock in the new linearization. Use Environments > Save As to save your environment with a new file name in the ColorBurst\Env folder (or a subfolder of the Env folder). If you do not save the environment, you will lose your new lin settings as soon as you change to a different environment.

Figure2.8.Save the environment to save the new lin as part of the environment.


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Relinearization Troubleshooting

Sometimes a printer, ink, and media combination can not be relinearized. However, in many cases a simple adjustment to the ink channel(s) that failed can result in densities that will fall within spec (0.0–0.3 above the baseline densities).

1. determine which inks are causing the error.When you load a lin file with measurements that are lower than the established Baselines, you will get an error message showing the low value(s) in bold. Values that are too high will not be indicated, so you will need to look at each value to make sure they are not more than 0.3 above the baseline densities. Make a note of any ink that does not fall within a range of 0.0–0.3 within the baseline density.

Figure3.1.An error message will indicate low lin values in bold.

note The upper range of 0.3 is a general guideline, depending on your media. If your densities slightly higher than 0.3 you may not need to make any adjustments, but the larger the difference, the greater the chance of color being off.

2. Verify settings before adjusting ink values.a. Check and make sure the paper in your printer matches the environment you are

relinearizing.

b. Perform a nozzle check test (at the front panel of your printer, check your manual for instructions) and do head cleanings if necessary until all nozzles are firing completely. If any nozzles were clogged you will need to repeat the relinearization process.


c. It is recommended that you use a spectrophotometer with a UV filter. All linear-izations provided with ColorBurst environments were created with a UV filtered spectrophotometer.

�. adjust ink densities and relinearize.If you have verified all of the above and the error continues, you will need to increase the Color Adjustment Ink Density level(s) for any ink that was too low, or reduce densities for inks that were too high. Go to Options > Color Adjustments and adjust the Ink Density values by 2% for each ink that was out of spec. Click OK to close the dialog and store the new value(s). Save your environment and repeat the relinearization process until the inks are all above the baseline densities.

Figure3.2.The ink density sliders in the Color Adjustments dialog can be adjusted to fix linearization errors.

�. linearization error when Ink density values are at 100%.If your Ink Density settings are at 100% and you are still getting linearization error messages, the current printer/paper/ink combination can not be relinearized to the Baseline values saved in the environment. A new linearization (with new Baseline values) and ICC profile must be made.

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Introduction to ICC Profiling

Creating a custom ICC profile offers the ultimate in color control. A custom ICC profile is tailored specifically to your printing environment. A profile is based on a combination of many factors including the printer model, media type, print resolution, ink type, and other print settings.

When you create a new ICC Profile using ColorBurst and SpectralVision Pro, you will be creating a new custom ColorBurst environment, a new linearization, and a new ICC profile.

This section will introduce you to the necessary steps in the correct order to create your own custom ICC profile.

overview of the Profiling Process

a) Select an existing ColorBurst environment as a starting point. Use “Save As” to save it as a new environment that will eventually use your new lin and profile.

b) Print a linearization target through ColorBurst.

c) Use SpectralVision Pro and a spectrophotometer to measure the target and save a new lin file.

d) In ColorBurst, load the new lin file and save the environment file.

e) Set the initial ink limit in ColorBurst.

f) Print the ICC Profile Targets through ColorBurst.

g) Evaluate the printed target for dryness and modify the ink limit if necessary.

h) Using SpectralVision Pro, read ICC Patches and build the ICC Profile.

i) In ColorBurst, select the new ICC Profile and Save the Environment file.

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Spectrophotometer Support and drivers

The following X-Rite devices are supported for creating ICC profiles in SpectralVision Pro.

DTP20 (PULSE) Eye-One

DTP22 Eye-One iO

DTP41/DTP41T Eye-One iSis

DTP45 Eye-One iSis XL

DTP530 iCColor

DTP70 SpectroScan

DTP938 SP62

DTP939

Device drivers for spectrophotometers are located in the ColorBurst\Profiling Tools & Docs folder. When connecting your device for the first time, use the New Hardware Found dialog to select the driver from the ColorBurst\Profiling Tools & Docs folder.

NOTE If you have already installed your spectrophotometer software or drivers you will not need to use the drivers in the ColorBurst\Profiling Tools & Docs folder.

for additional support

Please visit the online ColorBurst Technical Support Forum to read more about profiling and other color management topics. You can browse through existing forum threads, search the forum to find posts on a specific topic, or start a new thread with a question of your own. To access the ColorBurst forum go to www.colorburstrip.com and click on Support > ColorBurst Support Forum.


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The ICC Profiling Process

Step 1: Choose an environment to use as a starting point

The first step to building a custom Environment, Linearization, and ICC profile is to select a starting environment.

1. Select an environment.Use the Environment menu to choose the environment you want to relinearize. The following settings can not be modified in ColorBurst, so make sure to select the correct environment to relinearize based on:

• Direction (Bi-D or Uni-D) • Resolution (1440x1440, 1440x720, 720x720, 720x360, 540x720) • Dot Size (VL=Variable Large Dot, VS=Variable Small Dot, S=Small Fixed Dot) • Number of Print Passes (16P, 8P, 6P, 4P, 2P)

If an environment is not available for your exact media, choose an environment for a similar media type. The surface of your media should match the environment you select.

Figure5.1.Load an environment to use as a starting point for the new profile from the Environment menu.


note The Environment menu includes a group of Setup Environments with ENV files pre-configured for all available options. Existing Environments (3M, Avery, Epson, etc.) can also be used as a starting point for a custom Environment.

2. Save a new environment.Select Save As in the Environment menu to save your current environment with a new name. This new environment will be resaved as you go through the profiling process.

Figure5.2.Save the starting environment with a new name.

note Any of the listed entries in Media Manufacturer and Media Type can be selected for saving the new Environment to that group.

Step 2: linearize and set new baseline values

Before building an ICC Profile you must linearize your printer. You will then create a custom baseline for your particular printer, ink, and media combination. Linearization with a new baseline gives your new ICC profile a further level of customization and accuracy.

1. Perform a nozzle check on your printer.Use the front panel on your printer to perform a nozzle check. Verify that there are no missing jets. Correct as needed.

2. linearize.Follow the instructions for Relinearization, starting on page 6, to create a new lin file.

�. load your new lin file.In ColorBurst, open the Linearization Options dialog (Options > Linearization Options) and click the Select a lin file button to open the new lin file.

Figure5.3.Use the Select a lin file button to load your new lin file.


�. Verify your lin readings.After loading the new lin file, look at the Actual values listed in the Linearization Options dialog. The optimal ranges for these values are listed below.

glossy Media density Range Matte Media density Range

Cyan 1.80 – 2.0 1.3 – 1.4

Magenta 1.30 – 1.7 1.2 – 1.4

Yellow 1.0 – 1.1 0.9 – 1.1

Black 1.8 – 2.0 1.6 – 1.8

orange 1.6 – 1.8 1.3 – 1.5

green 1.6 – 1.8 1.3 – 1.5

note Lower print resolutions (540x720, 720x360) and banner materials will respond with lower densities than those shown above. Typical ranges can be 0.2 lower. Some matte medias with a very smooth surface can vary higher than the ranges shown above, which is fine as long as the linearization target is completely dry when it passes under the printer’s heaters after printing.

If your Actual values do not fall within these ranges for all inks, use the Color Adjust-ments dialog to modify the ink channel(s) that failed. See Section 3: Relinearization Troubleshooting for specific instructions.

�. Clear and set new baseline values.Once all of the ink density values are within the optimal ranges, click the Advanced button to open the Set Baseline Settings dialog. Click the Set Default Values button to create new baselines based on your new lin file. The Set Default Values button sets a baseline for each color just below the maximum values of the current Lin file. Click OK to close the Linearization Options dialog and lock in the new settings.

Figure5.4.Click the Set Default Values button to set new baselines for your new profile.

about baselinesA Baseline gives you “headroom” for future relinearizations of your environment over time. By setting a Baseline slightly lower than the actual measurements of your original lin file, you will still be able to successfully calibrate your system as it ages and changes over time.

6. Save your ColorBurst environment.In ColorBurst, you must save the environment with the new lin file and baselines. If you do not save the environment, your new settings will be lost as soon as you change environments.


note For easy reference, name the new lin file based on the media brand and type, reso-lution, bi-d or uni-d, print passes, dot size, and date.

Step �: Ink limiting

There are two ink limiting controls in ColorBurst, available at the bottom of the Linearization Options General tab.

1. Set initial ink limit values.In ColorBurst, open Linearization Options dialog (Options > Linearization Options) and go to the General tab. Make sure the Enable ink limiting checkbox is selected and set the following:

• Total Ink Limit = 250%

• Preserve Black = 50%

These are the optimal settings for ink limiting on most medias, and should be used as a starting point. These values can be changed later if necessary.

Figure5.5.Set the ink limit values at the bottom of the General tab in the Linearization Options dialog.

2. Save your ColorBurst environment.In the ColorBurst menu bar, select Environment > Save As to save your new ink limit as part of your custom environment.


Step �: Print and measure profiling patches

Now that you have linearized your printer, set new baselines, and set a total ink limit, you are ready to begin building an ICC profile. The settings you choose to build a profile with will have a significant effect on the outcome.

1. Perform a nozzle check on your printer.Use the front panel on your printer to perform a nozzle check. Verify that there are no missing jets. Correct as needed.

2. Send the ICC Profile target to the ColorBurst Job list.In ColorBurst, open the Linearization Options dialog and go to the Lin and Profile Targets tab. Select your device and click the Print Profile Target button to send the target file(s) to the Job List. The profile targets appear in the Job List in bold text to indicate that ICC color management will automatically be turned off when the targets are printed (linearization, ink limiting, and Color Adjustments settings are still applied). The target can be dragged back into the Job List to reprint without ICC, as long as the name is shown in bold text.

Figure5.6.Select a Profile Target and click the Print Profile Target button to send all pages of the lin target to the Job List with instructions to print without ICC color management.

note The Custom target option allows you to select any file to send to the Job List with instructions to print with color management off. Custom profiling targets for all devices with a variety of patch sets can be created in SpectralVision Pro.

�. Print the ICC target.In the Job List, make sure the target files have a “Ready” status and are at the top of the Job List. Click RIP On to begin printing.

note Some targets are more than one page long, and each page is sent to the Job List as an individual file. Make sure to print each page if you are using a target that is more than one page long.


�. evaluate the ICC target to determine if you need to adjust ink limiting.The initial ink limiting values (Total Ink Limit of 250% with Preserve Black at 50%) work with most medias, but sometimes an adjustment is needed. Look carefully at the ICC targets that you printed to see if the ink looks wet or displays any bleeding, or looks like it can hold more ink. If not, you can proceed to step 5.

If the media looks like it has too much ink:You will need to reduce the amount of ink by lowering the ink limiting values.

a) In the Linearization Options dialog, keep Ink Limit at 250% and set Preserve Black to 0%.

b) If your profile target files are still in the Done List, drag them back into the Job List to print, or use the Print Profile Target button to reprint the targets.

c) Evaluate the new prints for ink limiting. If the prints are not completely dry you can set the Ink Limit to 200% while keeping the Preserve Black at 0%.

note In the event that the patches are not acceptable and you are at the minimum settings (most ink limiting), then you must lower the channel ink limits of CMYK in the Color Adjustments dialog, typically by 5% per channel. In this case, a new Linearization target must be printed and loaded prior to checking the profile tar-gets for ink limiting.

If the media looks like it can accept more ink:Some canvas and fine art paper can hold quite a bit of ink without becoming too wet. The amount of ink can be increased by increasing the ink limiting values.

a) In the Linearization Options dialog, change the Ink Limit to 300% and keep Preserve Black at 50%.

b) If your profile target files are still in the Done List, drag them back into the Job List, or use the Print Profile Target button to reprint the targets.

c) Evaluate the new prints for ink limiting. If you want to increase the ink even more you can set the Ink Limit to 300% and Preserve Black to 100%.

�. Connect your device in SpectralVision Pro.Launch SpectralVision Pro, located in the ColorBurst\Profiling Tools & Docs\SpectralVision Pro folder (or use the desktop shortcut). In the Measure Target tab of SpectralVision, use the first pop-up menu on the left-hand side to select one of the Profile targets. This selec-tion should match the target you just printed for your device. The next pop-up menu, Measurement Device, will automatically change to the spectral device that supports the selected Target. After physically connecting your device to your computer via USB or Serial port, click the Connect button to allow communication between your device and SpectralVision Pro.


Figure5.7.Use the Target and Measurement Device pop-up menus to load a profile target, select a device, then use the Connect button to connect to your device.

6. Read the patches with your device.Once your device is successfully connected to SpectralVision Pro, calibrate your device (if necessary) and read the patches with your device. Follow the instructions on the screen or see your device’s documentation for device operation and calibration instructions.

Figure5.8.Read the profile target patches with your spectrophotometer to load the values into SpectralVision Pro.

Step 6: Build an ICC profile

After completing the measurement of your profiling patches, you can use SpectralVision Pro to build your ICC Profile.


1. open Profile Build options.In SpectralVision Pro, click the Build Profile button at the bottom of the window to open the Profile Build Options window.

Figure5.9.The Build Profile button in the Measure Target tab opens the Profile Build Options window.

2. Select a Preset.Select the predefined preset for your printer and inkset from the Presets pop-up menu. This will set all of the profile build settings to values optimized for the selected inkset.

Figure5.10.Select a preset in the Profile Build Options.

note Do not change any settings in the Ink Control and Extended Color tabs. The opti-mal values for these settings have already been set by selecting a preset.

�. Set custom ink settings.In the Ink Control tab, adjust the Black Generation , Ink Limiting, and black curve if desired. Click the Info button (“i”) or see pages 14–15 of this document for more information on these settings. Click the Next button when you are finished.

�. Set build options.Click the Build Profile tab and select a LUT Step Size (33x33x33 is recommended). Type in any information or notes about your profile in the Info Tag field. This information will be displayed in ColorBurst when you load the profile.


Figure5.11.Set the LUT Step Size and enter an Info Tag in the Build Profile tab.

�. Click Build.The Build button will begin the profile creation process. Save your profile in the ColorBurst\Profile folder. This can take several minutes to complete. The Build Status bar shows the profile build progress. The status will change to “Status Built” when the process is complete. You can then close the Profile Build Options and quit SpectralVision Pro.

Step �: load your new ICC Profile and save your environment

Your new ICC profile is ready to load into ColorBurst.

1. load your new ICC Profile.In the ICC Profile Options dialog, go to the Output Profiles tab. Use the Find button next to Printer Profile to locate your new ICC Profile. If the Find button is grayed out, click the On/Off button next to activate it. Click OK when done.

Figure5.12.Load your new ICC profile in the Output Profiles tab of the ICC Profile Options dialog.

2. Save your environment.This will save your final environment with all of your custom settings. You are now ready to print with your new environment and ICC Profile.


Figure5.13.Save the environment to save your new profile as part of the environment.


6

Technical Notes

Print Modes

The print mode (Bi-D vs Uni-D) affects the amount of ink used during printing. During profiling, the Color Adjustments CMYK Ink Density values are adjusted to balance the maximum ink density and total Ink Limit that the media can handle at the specified print mode. Faster print modes typically require lower CMYK densities and more overall ink limiting to allow the media to dry in time. Over-inking can cause poor print quality (dry banding) and the ink can remain tacky even after it has passed over the heaters.

Media types and ink densities

Glossy medias will have higher print densities than matte medias. Therefore, it is not neces-sary or possible to have matte medias operate at the same print densities as glossy medias. Each media group will have its own working range of print densities. Thicker medias such as canvas and heavy fine art medias can absorb more ink than many glossy vinyls yet their reported Print Densities will be lower.

CMYK Ink density Plateaus

Regardless of the working range of the print density of a media group, it is important that the individual ink densities (Color Adjustments - Ink Density) be limited such that each ink does not plateau at a value lower than 90% on the Linearization target. This can be determined by either “Spot Measurements” of the Lin target at 85%, 90%, 95%, and 100% of the CMYK patches or by reading the Lin target with SpectralVision Pro. At the Measurement Status click “ i “, to open the Info window, click the down arrow to view the Measurements, click Density to view the Measurements in Density. Click the 100%, 95%,


and 90% patches of each color to verify that the ink for that channel has not hit a plateau. For Orange, view the Magenta and Yellow levels, for Green view the Cyan and Yellow levels. If needed, lower the corresponding CMYK Ink Density value by 5%. Re-print the Lin target and re-check that each ink channel continues to increase in density, up to at least the 90% patch. Repeat as needed.

Maximum CMYK Ink density Setting

Regardless of how much ink a media can hold, do not set the Color Adjustment Ink Densities to 100%. Ideally, set all Ink Densities at 90% or lower. Magenta and Yellow will typically require higher ink density values than the other Inks. In special cases where an ink density is very low due to the resolution and dot size, set the ink density to 95%. This “head room” of 10% or more (90% or lower setting for the ink density) is needed for future relinearizations to have adjustment room for correction.

If any ink density remains too low, select a Setup Environment file with either a larger dot size or a higher resolution as the “Starting Point” environment.

note Due to the media (glossy adhesive vinyls), the dot size (VL vs VS), the print mode (Bi-d vs Uni-d) and the print speed (2 pass, 4 pass, 8 pass), the rule of the “90% Ink Density plateau test” may not be adequate to guarantee the media can dry in time, regardless of the Ink Limiting and Profiling settings.

Ink limit

The Ink Limit value range is from 200% to 300%. A setting of 200% will perform the most Ink Limiting but it will reduce the color of rich dark saturated colors, making them more black in their appearance. A setting of 300% limits less ink, but will only work when the media will hold a significant amount of ink and dries before passing the heaters. The optimal Total Ink Limit setting is 250%.

Preserve Black

Preserve Black allows the black ink to be limited independently of the other colors. Based on the Ink Limit value, all inks will be limited by some percentage. The Preserve Black percentage keeps that amount of black ink without limiting it. Therefore, Preserve Black at 100% instructs ColorBurst to perform no Ink Limiting on black ink. Preserve Black at 50% performs half of the intended Ink Limiting on the black ink. Preserve Black at 0% performs the same Ink Limiting on black ink as is being performed on the other inks.

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