ZePrA | Apply Photoshop color corrections to PDF files

Apply Photoshop color corrections to PDF files

In some applications it is not possible to use measurement based DeviceLink profiles. This is true, for example, if a customer brings print data and a print that should be as accurate as possible in the production run without a correct proof. If you view the print data on a monitor with a soft proof of the print standard for the production run, clear deviations from the print that you have brought with you can become visible.

In this case you could either print outside the standard and try to recreate the default – either by making gradation corrections in ZePrA or by using the capabilities of the printing press – or print inside the standard by applying Photoshop corrections to the PDF file. The latter has the advantage that you can proof the color-corrected data according to the standard and have it approved by the customer. This procedure requires an experienced Photoshop user and CoPrA’s Editing tool.

For a test with production data the demo version of the programs can also be used. To do this, meaningful objects must be combined from the existing PDF data into one file in Photoshop and combined with CoPrA’s test chart (EditTarget). This test file is then corrected under softproof conditions on the monitor. The edited image is imported into CoPrA and the corrections are taken into account in the created DeviceLink profile.

Then the DeviceLink profile can be used in ZePrA to correct the color of the original PDF data. If necessary, the corrections can be approved by the customer on a proof before printing. The printer can work as usual according to standard and reach the proof reliably.

The individual steps are described in detail in the chapter How to create DeviceLink profiles with edited charts in the CoPrA Help.

CoPrA | DeviceLink Iterate

Iterate

Improve DeviceLink profiles

Iterate

Overview

An existing DeviceLink profile can be optimized based on measured color values by using a test chart of your choice (can be created with ColorAnt/Custom Chart, see video turorial below). The iteration​test chart needs to be converted from source to target profile using the original DeviceLink profile and printed on the target printer. The measured color values of the printed test chart are then used to improve the conversion in order to achieve lower color differences and a more accurate reproduction of the source color space. Based on the measured values, it is automatically determined whether the target values are reached (which are determined by the source and target profiles) and a correction is made for deviations. Iteration is therefore particularly useful in proofing situations with absolute or relative colorimetric rendering intents. Perceptive rendering intents can also be used as a special feature of DeviceLink iteration in CoPrA. The iteration calculates a new DeviceLink profile based on the original DeviceLink profile and the measured values. The new profile can be reinserted for iteration until the desired result is achieved.

Iteration for Proofing and Production Printing

Iteration is a great method to get the best possible match for proofing. Proofing uses absolute colorimetric rendering without color exceptions. However, in digital production printing, perceptual rendering methods and color exceptions are used to keep colors pure. Nevertheless, there might be an interest to optimize the colors by iteration measurements (Note: It is not always recommended to do so, especially as out-of-gamut colors cannot be optimized).

Using the Iterate tool, it is possible to iterate data for production printing while retaining exceptions during the iteration process. CoPrA recognizes exceptions and rendering settings from the selected reference DeviceLink profile and retains them (only if the selected DeviceLink is a ColorLogic profile). A checkbox is shown when exceptions are used. By default, the checkbox is enabled. 

Notes

  • Iterate requires a DeviceLink license.
  • The test chart must match the color space of the source profile. 
  • Out-of-gamut colors of the original color space can only be improved to a limited extent. 
  • In proofing situations, the gamut of the target color space ought to be larger than that of the source color space, which makes iteration particularly interesting for DeviceLink profiles in proofing applications.
  • Iterations cannot be repeated arbitrarily due to fluctuations in print output, print material and the reproducibility of measuring instruments. More than 2-3 iterations are usually not necessary and not recommended.
  • Only DeviceLink profiles whose source and target profiles are available and referenced in the DeviceLink profile can be iterated. A warning is issued if the required source and target profiles are missing.
  • Third-party DeviceLinks that reference the used source and target profiles can also be iterated.
  • DeviceLinks that use color Exceptions and perceptual rendering options (such as conversion and separation profiles) can be iterated as well, but it should be done with care and it can only be done for ColorLogic DeviceLink profiles.
    Iteration allows the target values to be reached more accurately, which can result in a loss of channel purity if no exception settings are retained. Perceptive rendering intents require an interpretation of the measurement data, which can lead to slight shifts during iteration.
  • With a DeviceLink and a Multicolor license Multicolor DeviceLinks can be iterated, too.

Procedure

Procedure

Procedure

  1. Select Iterate in the sidebar or DeviceLink Iteration in the Navigation menu.
  2. Select the DeviceLink profile that you would like to iterate from the drop-down menu. Make sure that both the source and target profiles used in the DeviceLink are available in the ICC profile folder of your operating system, as CoPrA needs those to calculate the iterated profile. 
  3. Convert the test chart to be used for iteration with the DeviceLink profile and print it on the printer using the same settings as for the profiling test chart for this printer. The test chart can be converted using CoPrA’s Image Conversion tool.
    
Note: Use a test chart that contains the colors you would like to optimize. Typically, test charts with few color patches will suffice, but those patches must reflect the colors to be optimized. Therefore, using large profiling test charts is not required. Instead of using large test charts, use charts that can also be used to update profiles (see ColorAnt/Custom Chart tool). The color space of the test chart must correspond to the color space of the source profile of the DeviceLink.
  4. Measure the printed test chart in ColorAnt, save the measurement data and open it in CoPrA’s Iterate tool, either via drag-and-drop or via the Load button. Alternatively, click Measure and measure the test chart with CoPrA’s integrated Measure Tool.
  5. Depending on the selected DeviceLink profile and its settings, the checkbox Use same Settings from DeviceLink including exceptions will be activated or grayed out. It is activated for ColorLogic DeviceLink profiles that use Exceptions. If the DeviceLink is not a CoPrA profile or if it does not use exceptions, – which should be the default setting for proofing, – the checkbox is grayed out.
    Note: If the checkbox Use same Settings from DeviceLink including exceptions is deactivated, then all Exceptions are deactivated in the iterated DeviceLink profile.
  6. If you disable the checkbox Use same Settings from DeviceLink including exceptions,  then all exceptions are disabled in the iterated DeviceLink profile.
  7. Click Next to get to the Save dialog Format, Size and Further processing.
    Notes:
    a) The Default Template uses an option to add the iteration count number to each iterated DeviceLink.
    b) Size: It is recommended to select Auto because size matters for iteration. The Auto feature ensures that the highest precision is always used when creating the iterated DeviceLink.
    c) The newly created DeviceLink will have a more accurate color rendering for most in-gamut colors compared to the original DeviceLink profile. You can now use it in exactly the same way as the original one or use it for further iterations..
  8. If you would like to further optimize the DeviceLink, proceed as described above. However, select the previously iterated DeviceLink instead of the original one. Now convert the original test chart with the iterated DeviceLink (do not take the already converted test chart from point 3!) and use the measurement data of this printout to calculate a further optimized DeviceLink profile.

Format, Size and Further Processing

In the last step of profile creation, assign a Name and choose the Format and Size of the profile (see screenshot).

Name: Type in a Name for the profile.

Templates: Allows to select and combine name components from a list of options and save them as custom templates. The last selected template is used when creating new profiles, so the naming of profiles is automated.
Available naming options depend on the current profile type and include Date, Date/Time, Measurement data file name, Source and Target profiles, Name of the current preset and others. Each name component can be added at a user-defined position under Template (the position is selected with the mouse pointer). The Example section below shows the resulting name. Additionally, user defined text can be added at any position within the Template field.

Format: Define the Format of your profile. An ICC format in accordance with specification v2 is recommended as basic setting however, the newer format ICC v4 can also be chosen. In this case, please ensure that your programs support this format.
Note: ColorLogic products handle and use ICC v4 profiles consistently and correctly.

Size: The setting Large is recommended. The size specifies the number of grid points in the profile and determines the amount of disk space required for the generated profile. Small profiles should only be used for test purposes. Very Large profiles can slow down further processing in subsequent programs. Additionally, some programs are not able to handle very large profiles.

Further processing

Create Profile Report (PDF): Recommended to activate. The PDF report provides an overview of the quality of the profile based on statistics, diagrams of gray balances, gradients and gamut representations as well as color separations of converted test files.

Save Preview Profile: Is only available in Multicolor printer profiling. By activating this checkbox an ICC preview profile will be created in addition to the printer profile. It can be used as a soft proof profile in Adobe Photoshop.
Notes: Preview profiles are only suitable for proofing purposes. Either a preview profile or a CMYK profile can be created in one profiling step, but not both.

Embed profiles: Physically incorporates the used source and target profiles into the DeviceLink. This function is tricky and only recommended if the DeviceLink has to be transferred to a computer which does not have the required source and target profiles. It was implemented mainly for use with certain RIPs which only accept DeviceLinks with embedded source and target profiles.

Save: Creates the printer profile and saves it in the folder Profiles (macOS) or Color (Windows), (macOS: /Users/Username/Library/ColorSync/Profiles, Windows: C:\\Windows\\System32\\spool\\drivers\\color). Demo and encrypted profiles will be saved in a different location only relevant for ColorLogic applications.

Note: CoPrA-SP profiles are stored in the ColorLogic subfolder Licensed-Profiles.

Verifying the optimization

Verifying the optimization

ColorAnt can be used to verify a successful optimization. First create a “Lab Reference” to compare the measured values of the printouts to the values of the DeviceLinks. Use the ICC Transformation tool to create the Lab reference values by using the device values of the original test chart and the source profile and rendering intent of the DeviceLink. These Lab reference values now serve as comparison values after each application of the iterated DeviceLinks on your test chart. Compare the measurements of the iteration with the “Lab Reference” using the Compare tool in ColorAnt. 

You will notice that in-gamut colors of the iterated DeviceLink are closer to the Lab reference than those of the original DeviceLink.

Video Tutorial: How to create a test chart for iteration

Video Tutorial: How to iterate

CoPrA | DeviceLink Editing

Editing

Edit DeviceLinks using a reference chart

DeviceLink Editing

Overview

One of the most powerful features of CoPrA is the ability to create customized DeviceLink profiles based on individually adapted test charts (EditTargets). This smart way to create DeviceLink profiles opens up a multitude of possibilities.

Use this tool for recurring retouching work on similar image data, convert RGB data to CMYK or Multicolor data in a controlled way, factor in required gradation changes automatically into your data – the possibilities are almost unlimited.

These profiles can be used to automate color processing with software such as ZePrA.

Each EditTarget contains color patches for the color spaces RGB, CMYK or Gray in the upper left corner and includes the gray axis, primaries and secondary colors. These color patches are mandatory for the calculation of the DeviceLink profile and included in the calculation.

Open one of the provided EditTargets (for CMYK, RGB or Grayscale) in an image editing program (like Adobe Photoshop) and perform all desired color corrections. Additionally, other images may be added to the chart to fully adapt it to your requirements. Corrections, filters, masks and effects must include the test patch in the upper left corner to create a DeviceLink from the EditTarget.

Edit Targets included with CoPrA

About Edit Targets

The motifs of a test image play a central role in the creation, control and optimization of DeviceLink profiles. They should cover all areas that are significant for the application of the DeviceLink profile. Each color space which is used in conversions requires its own relevant test image, i.e. the color spaces Gray, RGB, CMYK and possibly Lab. Test images for these color spaces are provided by CoPrA (shown below).

Compilation of Photographic Motifs
The chosen photographic motifs should cover various areas such as skin tones, neutral tones, shadows, highlights and saturated colors. It is advisable to use test images which are applied industry-wide, such as the Roman16 test images of the ECI or the BVDM or images of the ISO (if available). Some of these images are included in the EditTargets provided by CoPrA (for example CLEditCMYK_Large_v31_144dpi.tif). Additional images from your production enhance the significance of the test images.

Gradients
Gradients are generally a critical factor in color conversions, both when using traditional ICC device profiles for source and target or when using DeviceLink profiles. The Homann Smoothness Inspection gradient test form is intended for the assessment of possible breaks or artifacts. It is included in the test file CLEditCMYK_Large_v31_144dpi.tif.

Pure CMY Colors
The test image should also have pure colors in various shades, particularly for CMYK-to-CMYK conversions. They should be positioned at the edge of the test image and should be large enough to allow direct comparison and measurement before and after conversion. This is important on proofs, for the use of colorimeters or the eyedropper tool in Photoshop.

How to create DeviceLink profiles with edited charts

To incorporate any desired color transformation into a DeviceLink profile, like global corrections or selective color corrections, this color transformation has initially to be integrated into the selected EditTarget using an image editing software (for example Adobe Photoshop).

Open the desired test chart (EditTarget) in your image editing software in the appropriate color space (the color space from which the color conversion will be performed). The provided EditTargets can be found in the EditTargets folder (in CoPrA in the menu Tools > Open EditTargets folder or in Windows: C:/Program Files(x86)/CoPrA5/EditTargets and in macOS: Applications/CoPrA5/EditTargets). When you have modified the EditTarget and saved it under a new name, open it in the tool Editing, either by drag and drop or by using the button Select Edited Testchart.

If a profile is embedded in the opened EditTarget, it will automatically be selected as target color space. The source profile has to be selected manually. If there is no embedded profile, the source and the target profile can be assigned manually. Assigning profiles is useful as color patches will then be displayed with true colors in CoPrA as well. A further advantage of edited DeviceLinks with assigned source and target profiles is that this profile information is stored in the PSID tag of the profile, so it can be used by intelligent workflow solutions like ColorLogic’s color server ZePrA to automatically create configurations.

Note: All profile drop-down menus function like search fields. Simply type in some letters of the desired profile and only those profiles containing these letters will be shown in the list. To select a profile simply click on it. Alternatively, you may open the drop-down menu with the little arrow on the right and select a profile from the full list as usual.

You can now assess the modifications for each color patch. Here, the original unedited EditTarget is used as a reference. The reference value of each color patch is located in the upper left half of the diagonally split color patch, the edited value is in the right lower half. If you move the mouse pointer over the chart, the color patches will be displayed along with other color information including a difference display in parentheses (color space and TAC value).

Purify Colors
In contrast to the exceptions in conventional DeviceLink profiling, the exceptions under Purify Colors in the tool Editing ensure that any contamination caused by editing of the test chart will be removed but not recalculated. Among other things, these exception rules define how pure colors, colors, gray, duplex and triplex colors are structured in the DeviceLink. The selection of these rules considerably determines the quality of your DeviceLink profile.

All color patches that are affected by the selected exception will be highlighted in the graphical representation by a red border. If you move the mouse pointer over a color patch it is emphasized by a black or white border and the values of the source and target color space are displayed. By pressing the ‘Alt’ key on your keyboard the color patch will be captured allowing you to check quickly and easily whether and to what extent it is affected by an exception. Exceptions which are not available are grayed out. This may be the case when a dependency between exceptions exists, or when exceptions are not relevant for a specific color space.

100% Black: Protects 100% black, so 100% K remains 100% K and will not be supplemented with or replaced by CMY. Additional color portions will be deleted.
For a conversion of an RGB source profile into a CMYK target color space 100% Black ensures that an RGB value of 0, 0, 0 is converted to 100% black. For example, it prevents pure black RGB text from being composed of four colors in the CMYK profile after the conversion.

Gray: Protects the single color structure of black from 0 to 100%. Additional color portions will be deleted.

Duplex (a primary color plus black): Prevents color contaminations of duplex colors. If editing of the test chart caused contaminations of duplex colors by adding primary colors, these impurities will be removed.

Triplex (two primary colors plus black): Prevents color contaminations of triplex colors. If editing of the test chart caused contaminations of triplex colors by adding primary colors, these impurities will be removed.

100% C,M,Y: Protects cyan, magenta and yellow. The 100% values of C, M and Y are retained after the color conversion at 100%. Additional color portions will be deleted.
The slider
Range specifies how far adjacent color patches are included.

100% R,G,B: Protects pure red, green and blue. The 100% key values of red, green and blue are retained after the color conversion at 100%.
The slider
Range specifies how far adjacent color patches are included.

Primaries: Protects the single color structure of primary colors.

Secondaries: Protects the two color structure of secondaries.

Range: The slider Range allows to specify how far adjacent color patches will be included. All color patches that are affected by the selected exception are highlighted in the graphical representation by a red border showing the color areas which are affected immediately after moving the slider. Move the slider to a high value to avoid hard edges, move it to a low value to increase color accuracy.

Profile Processing

Format, Size and Further Processing

Name: Type in a Name for the profile.

Templates: Allows to select and combine name components from a list of options and save them as custom templates. The last selected template is used when creating new profiles, so the naming of profiles is automated. 

Available naming options depend on the current profile type and include Date, Date/Time, Measurement data file name, Source and Target profiles, Name of the current preset and others. Each name component can be added at a user-defined position under Template (the position is selected with the mouse pointer). The Example section below shows the resulting name. Additionally, user defined text can be added at any position within the Template field.

Format: Define the Format of your profile. An ICC format in accordance with specification v2 is recommended as basic setting however, the newer format ICC v4 can also be chosen. In this case, please ensure that your programs support this format correctly.
Note: ColorLogic products handle and use ICC v4 profiles consistently and correctly.

Size: The setting Large is recommended. The size specifies the number of grid points in the profile and determines the amount of disk space required for the generated profile. Small profiles should only be used for test purposes. Very Large profiles can slow down further processing in subsequent programs. Additionally, some programs are not able to handle very large profiles.

Further processing

Create Profile Report (PDF): Recommended to activate. The PDF report provides an overview of the quality of the profile based on statistics, diagrams of gray balances, gradients and gamut representations as well as color separations of converted test files.

Save Preview Profile: Is only available in Multicolor printer profiling. By activating this checkbox an ICC preview profile will be created in addition to the printer profile. It can be used as soft proof profile in Adobe Photoshop.
Notes: Preview profiles are only suitable for proofing purposes. Either a preview profile or a CMYK profile can be created in one profiling step, but not both.

Embed profiles: Physically incorporates the used source and target profiles into the DeviceLink. This function is tricky and only recommended if the DeviceLink has to be transferred to a computer which does not have the required source and target profiles. It was implemented mainly for use with certain RIPs which only accept DeviceLinks with embedded source and target profiles.

Save: Creates the printer profile and saves it in the folder Profiles (macOS) or Color (Windows), (macOS: /Users/Username/Library/ColorSync/Profiles, Windows: C:\Windows\System32\spool\drivers\color). Demo and encrypted profiles will be saved in a different location only relevant for ColorLogic applications.

Note: CoPrA-SP profiles are stored in the ColorLogic subfolder Licensed-Profiles.

Preview Profiles

Introduction: Using Preview Profiles for Soft Proofs

Preview profiles allow soft proofing of image files in DeviceLink profiling and Multicolor printer profiling, without converting a file. Multicolor preview profiles provide a true color representation of images to be converted into the Multicolor color space in order to review the achievable result prior to the actual Multicolor conversion (More information can be found further down in the text). The same applies to DeviceLink conversions. Here, too, the DeviceLink preview profile can be used in Photoshop with the original data to visually review how the result of such a conversion would look like.

Preview profiles can be created together with DeviceLink or Multicolor printer profiles by activating the checkbox Save Preview Profile (see screenshots). Preview profiles have the suffix ‘preview‘ and are saved in the folder Profiles (macOS) or color (Windows), (macOS: /Users/Username/Library/ColorSync/Profiles, Windows: C:\Windows\System32\spool\drivers\color). Right clicking on the preview profile and selecting the menu entry Show file in the context menu will take you directly to the location of the selected profile.

Creating preview profiles in Multicolor printer profiling.

Creating preview profiles in DeviceLink profiling.

A preview profile is a printer profile with the same color space as the source profile of the DeviceLink. It can be used as soft proof profile, for example in Adobe Photoshop. Preview profiles can be created for the following DeviceLink combinations:
RGB-to-CMYK, CMYK-to-CMYK, RGB-to-Multicolor and CMYK-to-Multicolor

Note: The creation of preview profiles is not available for DeviceLink profiles using more than four channels in the source color space since only preview profiles of the color spaces Gray, RGB or CMYK can be used in Photoshop. Multicolor printer profiles are not affected as their preview profiles are always RGB profiles which can be used in Photoshop.

Example: To adapt your RGB image data in RGB mode to the desired CMYK printing condition, use the preview profile of your RGB-to-CMYK DeviceLink as soft proof profile in Adobe Photoshop to check how the image would look like after the conversion. This allows specific RGB adjustments without the need to convert the RGB file early on. A preview profile is a very useful feature, particularly in view of storing RGB image data in media-neutral workflows.

Preview profiles can also be created for Multicolor printer profiles which allows a true color simulation of the color representation prior to application of the Multicolor profile. Although Adobe Photoshop CS4 or higher is able to convert image data using Multicolor profiles, the display of multichannel files is not a true color representation in Photoshop. So far, a true color representation of multichannel files is only possible using additional plug-ins and causes an increased workload. The preview profile function generates an RGB printer profile which features the same color visualization as the original Multicolor profile. Use this preview profile on an original image data for soft proofing.

Note: Preview profiles are only intended for soft proofs and should never be used for the actual conversion. A preview profile provides an excellent visual preview of the expected result of a DeviceLink conversion. However, the special features of the DeviceLink, such as preserving color purity, cannot be 100% emulated.

Using Preview Profiles for DeviceLinks in Adobe Photoshop

  1. Open the original image data to be converted using a DeviceLink profile in Adobe Photoshop.
  2. Either assign the Preview profile from CoPrA to this image file, or select the Preview profile in the dialog Customize Proof Condition as Device to Simulate (see screenshot).
    Note: The color space of the preview profile is based on the color space of the DeviceLink’s source profile. It is an RGB preview profile for RGB-to-CMYK DeviceLinks and a CMYK preview profile for CMYK-to-CMYK DeviceLinks.
  3. Click Preserve CMYK Numbers to get a virtually exact preview of the expected color representation for the DeviceLink conversion.
    Note: Pipette values do not correspond to the final DeviceLink conversion. Only the color representation in the soft proof does.

Using Multicolor Preview Profiles in Photoshop

  1. Open the original image data to be converted using a Multicolor printer profile in Adobe Photoshop (for example an RGB image).
  2. Select the Preview profile from CoPrA in the dialog Customize Proof Condition as Device to Simulate. Find the profile in the list of RGB profiles. The naming is based on the Multicolor profile name: Profile name_preview.icc
  3. Select the desired Rendering Intent and disable the checkbox Preserve RGB/CMYK Numbers.
    Note: Eyedropper values do not correspond to the final DeviceLink conversion. This is only for a soft proof.
Profile Reports

Profile reports can be created for Printer or DeviceLink profiles. To do so, activate the checkbox Create Profile Report in the last step of the profiling or, when updating profiles, the checkbox Create Profile Comparison Report.

Depending on the type of profile the report contains various statistical data, such as statistics about profile precision (Integrity, Precision, Black Point, White Point etc.), graphic representations of curves and gamuts (Gray Balance, Gradients etc.), conversions of test images, separations and color patches to evaluate the smoothness or the purity of colors. All this facilitates the detection of artifacts that may be present.

Profile reports can be created at any time in Batch Overview or in Profile Manager which, by the way, is not restricted to ColorLogic profiles.

Under Preferences you can define some basic settings for the creation of the profile report, such as the file location, the report format (PDF or XML) or the DeltaE method (dE76 or dE2000).

Note: If a profile comparison report is created when updating a profile, the measurement data obtained from the update test chart will be compared to the data of the original profile (reference profile).

If the checkboxes Brightener Compensation or Measurement Correction have been activated, the data of the original profile will not be compared to the measurement data from the update test chart but to the data modified by these options.

CoPrA | DeviceLink Linearization

Linearization

Optimize tone values for any printer and color combination

DeviceLink Linearization

Optimizing tone values of primary gradation ramps

The Linearization tool optimizes the tone values of primary gradation ramps for any printer and color combination including Multicolor. The goal of Linearization is for adequate differences from white to 100% of primary inks, to smooth gradation curves and to bring primary colors to a defined and reproducible state.

Note: The Linearization tool is included with CoPrA 5 L and higher.

The linearization methods of this tool are based on ISO 20654, ColorLogic’s proven default calibration method or G7 calibration. It also provides a setting to protect the highlights which is important for Flexo printers and G7 calibration of difficult media and printers. All settings can be used for CMYK and Multicolor measurement data and there is a setting which allows the use of G7 for the CYMK parts of Multicolor data and ISO 20654 for the additional colors as G7 is only intended for CMYK. RGB is not supported.

Detailed Procedure

Load or Measure Data

The creation of a Linearization DeviceLink starts with printing a linearization test chart on the uncalibrated printer without any color management.

There are two ways to get the necessary measurement data for the creation of a Linearization DeviceLink profile:

  1. Measure the test chart and optimize the measurement data using appropriate software, such as ColorAnt (using the tools Custom Chart and Export Chart) and open the measurement data in CoPrA’s Linearization module.
  2. Measure the linearization test chart by using CoPrA’s own Measure Tool.

Load: Opens and displays existing measurement data files. Alternatively, drag and drop the data into the window, to extract and view the data.

Measure: Opens the Measure Tool to measure the linearization test chart with a supported device.

Setting: Select the linearization method. CoPrA contains three [PREDEFINED] settings (Default, Flexo Linearization, G7 Linearization). These settings can be [EDITED] and [SAVED].

Customize: Allows fine tuning of the linearization setting by selecting the Calculation Mode and adjusting the Protect Lights (%).

Fit to Width: Fits the color patches of a row to the window width. Especially for large test charts with very many color patches and many rows the color patches will be displayed larger.

Show reference data: The device values such as CMYK or Multicolor and measurement data (i.e. Lab or spectral values) are shown on a split color patch. The data can be quickly compared for incorrect or faulty data.

Linearization Options

Calculation Mode: This setting defines the method to calculate the colorimetric linearity. Six standard methods are available which can be customized and saved.

ColorLogic Default (colorimetric linearization): Linearizes the curves based on Lab/dE-76 which means that a 50% value of a primary has the same distance to the left (white) as to the right (full tone) and is therefore located at the midpoint of the graphic.

Linearization according to ISO 20654: Linearizes the tone values of primary gradation ramps based on linearity according to ISO 20654.
Note: The methods ColorLogic Default and Linearization according to ISO 20654 are very similar. However, in contrast to the ISO 20654 approach, ColorLogic Default takes the hue of primaries into consideration.

Linearization according to G7 (CMYK only): The CMYK tone value curves are linearized to match the gray balance requirements of the G7 calibration process. Additional Multicolor channels are not affected.

Linearization according to G7 (CMYK) and ISO 20654 (spot colors): G7 is defined to work with CMYK only. The additional Multicolor channels are not affected. Therefore, activating this setting applies the G7 procedure to the CMYK parts of a Multicolor measurement file and the ISO 20654-based method to the remaining Multicolor channels.

ColorLogic Default (colorimetric linearization) with automatic channel limit: Same as ColorLogic Default (colorimetric linearization), but with enabled ink limiting function. See note below for more information.

Linearization according to ISO20654 with automatic channel limit: Same as Linearization according to ISO20654, but with enabled ink limiting function. See note below for more information.

Note on ink limiting for Linearization DeviceLinks

Ink limiting during linearization is necessary if ink channels are saturated and do not provide sufficient differentiation between the individual color values at higher ink densities. This is typically done by printing a step wedge and then visually determining the percentage up to which a good differentiation exists. The ink channel is then limited at this value. We have added an automatic channel limit function that does exactly this based on the saturation values of the measurements. This function has been added to the two calculation modes ColorLogic Default and Linearization according to ISO20654.

Note: For the G7 mode the channel limit function has not been made available as this would contradict the G7 linearization methodology. Ink limiting should be done before applying G7.

Protect Lights (%): Protects highlight areas. Values below the set percentage are protected and will not be linearized. Make sure to get a smooth transition from the protected – non-linearized – highlights to the linearized part of the measurement data.
Note: For linearization of the entire measurement data, set the slider to 0.

The curves graphic allows assessment of the linearization results based on the selected settings. Use the two radio buttons to compare the Calculated Curves – which will lead to a linear behaviour of the printer when applied – to the original CMYK and Multicolor curves (Curves from Data).

Calculated Curves: Represent the curves based on the selected settings that will be applied in the resulting Linearization DeviceLink profile.

Curves from Data: Shows the original non-linearized curves. The graph is a colorimetric representation of the curves according to ISO 20654. Linear curves indicate a printer in a perfectly calibrated state according to ISO 20654.

Click Next and define the profile settings. Generate a Profile Report to get all important details about the DeviceLink profile.

Note: The generated Linearization DeviceLink profile can be used in a workflow for any kind of printing process. For example, it should be used when printing a profiling test chart on an uncalibrated printer. ColorLogic ZePrA supports the use of Linearization DeviceLinks as gradation curves. This way the linearization can be applied to a workflow like curve corrections in a RIP. In this case, curve corrections must be disabled on RIP level to avoid double changes.

Profile Processing

Format, Size and Further Processing

Name: Enter a name for the profile.

Templates: Allows to select and combine name components from a list of options and save them as custom templates. The last selected template is used when creating new profiles, so the naming of profiles is automated. 

Available naming options include Date, Date/Time, Measurement data file name, Source profile, Name of the current preset and others. Each name component can be added at a user-defined position under Template (the position is selected with the mouse pointer). The Example section below shows the resulting name. Additionally, user defined text can be added at any position within the Template field.

Format: Define the Format of the profile. If the ICC v4 format is chosen, please ensure that your programs support this format correctly.

Note: ColorLogic products handle and use ICC v4 profiles consistently and correctly.

Size: The size typically specifies the number of grid points in the profile. However, for linearization DeviceLink profiles they are of no relevance as only TRCs (tone reproduction curves) are generated.

The two options Small and Large affect the number of data points saved in the ACV and XML formats. Small creates 11 points for ACV and XML while Large creates the full flavoured 51 points for XML and 16 for ACV. The size does not affect the ICC DeviceLink profile created as it always uses the highest precision.

Further processing

Optionally, linearization curves can either be saved as Photoshop ACV files or as XML files according to the format definitions in ISO 18620:2016.

Save curves as Photoshop ACV format: Linearization curves, saved in the Adobe Photoshop Curve format (ACV), can be imported in Photoshop and applied to images.

Save curves as ISO 18620:2016 XML format: ISO 18620:2016 specifies a simple extensible XML format for the exchange of tone adjustment curves between applications including but not limited to color management, calibration and raster image processor systems. Some RIPs such as Esko Colorpilot support this format which allows to import and use the high quality curves generated by CoPrA.

Note: The curves are saved with the same name as the ICC profile in the User/Documents/CoPrA/Linearization folder.

Create Profile Report (PDF): Recommended to activate. The PDF report provides an overview of the quality of the profile.

Profile Reports

Profile reports can be created for Printer or DeviceLink profiles. To do so, activate the checkbox Create Profile Report in the last step of the profiling or, when updating profiles, the checkbox Create Profile Comparison Report.

Depending on the type of profile the report contains various statistical data, such as statistics about profile precision (Integrity, Precision, Black Point, White Point etc.), graphic representations of curves and gamuts (Gray Balance, Gradients etc.), conversions of test images, separations and color patches to evaluate the smoothness or the purity of colors. All this facilitates the detection of artifacts that may be present.

Profile reports can be created at any time in Batch Overview or in Profile Manager which, by the way, is not restricted to ColorLogic profiles.

Under Preferences you can define some basic settings for the creation of the profile report, such as the file location, the report format (PDF or XML) or the DeltaE method (dE76 or dE2000).

Note: If a profile comparison report is created when updating a profile, the measurement data obtained from the update test chart will be compared to the data of the original profile (reference profile).

If the checkboxes Brightener Compensation or Measurement Correction have been activated, the data of the original profile will not be compared to the measurement data from the update test chart but to the data modified by these options.

CoPrA | SaveInk

SaveInk

Create SaveInk DeviceLinks

SaveInk DeviceLinks

Introduction

An important application of DeviceLink profiles is ink saving while maintaining the visual color appearance. Today, SaveInk profiling (sometimes referred to as ink optimization) is a popular application for saving ink and enhancing quality in standardized offset, gravure and newspaper printing. Its application in large-format printing is interesting and should be evaluated for cutting the cost of ink consumption.

SaveInk DeviceLink profiles can be created from CMYK or Multicolor profiles.

Multicolor profiles can only be used if a black channel is present as the fourth channel. Profiles that do not follow those rules cannot be used.

Note: The SaveInk tool requires a SaveInk license, the creation of Multicolor SaveInk profiles requires an additional Multicolor licence. ZePrA supports Multicolor SaveInk DeviceLinks (from ZePrA 7 and higher). However, sharing of Multicolor SaveInk presets with ZePrA 7 is not supported. Hence the checkbox Share with ZePrA is disabled for Multicolor.

Creating SaveInk Profiles

Selecting a Profile and a Setting
  1. Open the tool SaveInk and select the printer profile to use for the creation of a SaveInk profile.
    Note: All profile drop-down menus function like search fields. Simply type in some letters of the desired profile and only those profiles containing these letters will be shown in the list. To select a profile simply click on it.
    Alternatively open the drop-down menu with the little arrow on the right and select a profile from the full list as usual.
  2. Select a predefined Setting for the SaveInk calculation from the drop-down menu.

    Predefined settings for SaveInk profiles


    SaveInk Settings

    Default: Use this setting as a starting point, if other presets are not suitable for your print process.

    Extreme: Highest ink saving, but with slight visual flaws to the original.
    Note: This preset may reduce Secondaries, Duplex and Triplex colors if ink can be saved. If you explicitly want to maintain 200% inks for red, green and blue tones, you should use the slider to reduce the dE-Tolerance instead.

    Maximum: Maximum color savings with colorimetric accuracy still very high while maintaining the visual color impression. The colorimetric accuracy is best with a dE-Tolerance of 0. This setting requires experienced printers and an excellent command of the standardization.

    SaveNeutral Gravure – SaveNeutral Offset TAC 300: Use these settings for gravure or offset printing. These settings moderately increase the black content in neutral color areas. This is ideal for print shops who are looking for a quick introduction to saving ink and want to gain practical experience. These profiles are mainly used to stabilize the printing process and are less suitable for saving ink.

    SaveStrong Gravure – SaveStrong Offset TAC 300: Use these settings for gravure or offset printing. They greatly increase the proportion of black and are aimed at printers who have their printing process under control according to the standardization and who want to achieve high ink savings, but still want to leave room for adjustments on the press.

    TAC-Limit300 – TAC-Limit220: TAC-Limit profiles do not perform any color conversion and limit only the total amount of color without strongly interfering with the color composition. Use TAC-Limit300 for offset printing and TAC-Limit220 for newspaper printing, for example.

  3. Customize allows you to specify the Method, the Total Amount of Color, the Ink Saving and to define Exceptions.
Customizing SaveInk Settings

Method

There are two methods available to specify the basic settings for Ink SavingStandard and Advanced.

SaveInk Methods

Standard: Reduces the settings a user needs to define to a minimum but still achieves economical high quality profiles. Only three settings have to be adjusted: the Total Amount of Color, the Ink Saving slider and the exception Preserve 0% Black. Use this method to get quick results.

Advanced: Allows the user to also define Black Start, Black Width and Exceptions. Use this method to define more precisely how the ink saving performs. When selecting the same settings as in the standard method it will produce identical results.

Total Amount of Color for SaveInk Profiles

The feature Total Amount of Color allows the tonal value limit to be set for your SaveInk profile. Print data which are converted using the SaveInk profile will be limited to the total area coverage set in the profile. The maximum black value is controlled and adjusted automatically.

Setting the Total Amount of Color

Use Mode to specify whether the total area coverage and the maximum black value are to be adopted from the Profile, will be defined manually using Custom or will be calculated automatically using Auto. The maximum black value, the total area coverage and the darkest L* value will be calculated according to the selected method and will be displayed after a short processing. These values reveal, for example, whether a reduction of the total area coverage will result in brightening of the shadows. Brightening can be identified by an increase of the L* value.

Notes:

  1. In most cases, the mode Auto produces the best results. Assuming the printer profile allows it, it will calculate a slight reduction of the total area coverage without increasing the L* value significantly.
  2. When using the methods Maximum or Extreme while strongly reducing the total area coverage as well, an identical Lab measurement mapping is possible only to a limited extent.
  3. If the TAC is below 200% the exception Preserve Secondaries is available.

Ink Saving

Ink Saving Options

Ink Saving: Defines the replacement of composite black (CMY) by pure black. The higher the slider setting, the more colored ink is replaced by pure black. So higher slider settings achieve higher ink savings, but at the expense of the colorimetric accuracy.

Black Start: Defines the starting point for the replacement of composite black (CMY) by pure black. Pure black will be used above the entered value.

Black Width: Defines the range in which black is used outside the color-neutral area. The higher the value, the more black will be used outside the color-neutral area.

dE Tolerance: Allows tremendous ink savings when set to a high dE tolerance. Increases the maximum deltaE between the original profile and the SaveInk DeviceLink profile which results in greater ink savings. In contrast, the predefined settings SaveNeutral, SaveStrong and Maximum use a low dE tolerance setting of 0 deltaE ensuring a very high color and visual accuracy of the profile. However if greater ink savings are desired it can only be done by reducing the visual accuracy, hence a higher dE tolerance setting is required. The ink saving preset Extreme uses a high dE tolerance.

Note: Users can save on ink even more by using a higher dE tolerance setting. We recommend to test ink saving profiles with high dE tolerance settings closely before using them in production.

Exceptions in SaveInk Profiling

Exceptions define the colors to be excluded from ink saving when creating SaveInk profiles.

Setting Exceptions in SaveInk Profiles

Preserve 0% Black: Areas which are built with CMY only (without black) remain unchanged by the SaveInk optimization. This is particularly important when overprinting with CMY colors but results in a considerably reduced ink saving.

Preserve Secondaries: Is only available when the total area coverage (TAC) is set to values below 200%. It allows to obtain highly saturated secondary colors without reduction, although the total area coverage is reduced below 200%.
There is a tendency in current newspaper printing and high-speed InkJet printing to use a TAC of less than 200%. This may result in an unwanted reduction of secondary colors (those who need at least 200% ink) and thus result in washed out colors. Total area coverages over 200% always preserve secondary colors, however, without this exception a reduction below 200% would also reduce red, green and blue tones. This can be avoided by activating this exception as it ensures that full red, green and blue tones remain unchanged while the TAC of dark colors and of the black point is deceased below the set total area coverage of 200%.

Preserve Secondaries is only available if the TAC is below 200%

Preserve Skin Tones: Excludes skin tones from ink saving. This is an approach especially important for printing systems with coarse raster frequencies (for example, large format InkJet systems with low resolution, newspaper printing or printing processes subject to the ‘Missing Dot’ problem) to reduce the so called peppering effect, visual graying or troubled skin tones.

Note: Exceptions to Preserve Skin Tones and Custom exceptions are not available for Multicolor profiles and are grayed out.

Custom: Specify individual CMYK color values to be excluded from ink saving. These could include specific company colors or corporate identity colors that must remain unchanged. Select Edit to open a window where the CMYK color values can be entered that will be excluded from the SaveInk optimization.

Setting Exceptions for Specific Values

Define Custom Exceptions:

  1. New creates an entry for a new color.
  2. Under Value, enter the CMYK value to be excluded from SaveInk conversion. Optionally, assign a name for this color.
  3. Enter as many colors as required.
  4. Activate the checkbox Enabled to select the colors to be excluded.
  5. Click OK to confirm these values.
  6. Make sure to enable the checkbox Custom.

Profile Settings

Format, Size and Further Processing

Name: Type in a Name for the profile.

Templates: Allows to select and combine name components from a list of options and save them as custom templates. The last selected template is used when creating new profiles, so the naming of profiles is automated.

Available naming options depend on the current profile type and include Date, Date/Time, Measurement data file name, Source and Target profiles, Name of the current preset and others. Each name component can be added at a user-defined position under Template (the position is selected with the mouse pointer). The Example section below shows the resulting name. Additionally, user defined text can be added at any position within the Template field.

Format: Define the Format of your profile. An ICC format in accordance with specification v2 is recommended as basic setting however, the newer format ICC v4 can also be chosen. In this case, please ensure that your programs support this format correctly.
Note: ColorLogic products handle and use ICC v4 profiles consistently and correctly.

Size: The setting Large is recommended. The size specifies the number of grid points in the profile and determines the amount of disk space required for the generated profile. Small profiles should only be used for test purposes. Very Large profiles can slow down further processing in subsequent programs. Additionally, some programs are not able to handle very large profiles.

Further processing

Create Profile Report (PDF): Recommended to activate. The PDF report provides an overview of the quality of the profile based on statistics, diagrams of gray balances, gradients and gamut representations as well as color separations of converted test files.

Embed profiles: Physically incorporates the used source and target profiles into the DeviceLink. This function is tricky and only recommended if the DeviceLink has to be transferred to a computer which does not have the required source and target profiles. It was implemented mainly for use with certain RIPs which only accept DeviceLinks with embedded source and target profiles.

Save: Creates the printer profile and saves it in the folder Profiles (macOS) or Color (Windows), (macOS: /Users/Username/Library/ColorSync/Profiles, Windows: C:\Windows\System32\spool\\drivers\color). Demo and encrypted profiles will be saved in a different location only relevant for ColorLogic applications.

Note: CoPrA-SP profiles are stored in the ColorLogic subfolder Licensed-Profiles.

Profile Reports

Profile reports can be created for Printer or DeviceLink profiles. To do so, activate the checkbox Create Profile Report in the last step of the profiling or, when updating profiles, the checkbox Create Profile Comparison Report.

Depending on the type of profile the report contains various statistical data, such as statistics about profile precision (Integrity, Precision, Black Point, White Point etc.), graphic representations of curves and gamuts (Gray Balance, Gradients etc.), conversions of test images, separations and color patches to evaluate the smoothness or the purity of colors. All this facilitates the detection of artifacts that may be present.

Profile reports can be created at any time in Batch Overview or in Profile Manager which, by the way, is not restricted to ColorLogic profiles.

Under Preferences you can define some basic settings for the creation of the profile report, such as the file location, the report format (PDF or XML) or the DeltaE method (dE76 or dE2000).

Note: If a profile comparison report is created when updating a profile, the measurement data obtained from the update test chart will be compared to the data of the original profile (reference profile).

If the checkboxes Brightener Compensation or Measurement Correction have been activated, the data of the original profile will not be compared to the measurement data from the update test chart but to the data modified by these options.

CoPrA | DeviceLink Profiling

DeviceLink

Create DeviceLinks for a variety of print methods

Creating DeviceLinks

Overview

DeviceLink profiles offer some advantages in comparison to device profiles:

  • DeviceLink profiles perform a direct conversion between input and output color spaces. Color values or color combinations can be protected or individually customized and will only be altered where necessary.
  • DeviceLink profiles compensate for many weak points of conversions using ICC output profiles. For example, the DeviceLink allows preservation of the black channel so that black text is printed with black ink rather than using four inks.
  • Ink can be saved (SaveInk) or the total area coverage (TAC) reduced without altering other color areas.
  • In proofing iterated DeviceLinks also provide a substantially increased proof quality.

Supported Color Systems

CoPrA allows to create DeviceLinks for all types of color spaces Gray, RGB, CMYK and Multicolor. Cross color space profiles are also supported, such as RGB to CMYK, CMYK to Grayscale or RGB/CMYK to Multicolor.

The following color systems are supported:

  • 2- and 3-color systems
  • 4-color systems with CMYK
  • 4-color systems with CMY + either Red or Green or Blue, without Black
  • 5-color systems: CMYK + either Red or Green or Blue
  • 5-colour systems: CMY + either Red+Green, Red+Blue or Green+Blue, without black
  • 6-colour systems: CMYK + either Red+Green, Red+Blue or Green+Blue
  • 6-colour systems: CMY + Red+Green+Blue, without Black
  • 7-colour systems: CMYK + Red+Green+Blue
  • 8-color systems: CMYK + Red+Orange+Green+Blue
  • 9-color systems: CMYK + Red+Orange+Green+Blue+Violet
  • The CMY channels can even be exchanged for other similar colors, e.g. Magenta for another reddish color or Yellow for Beige and so on.
  • Creation of DeviceLinks with up to 9 channels

Arguably, the most important applications are conversions of CMYK-to-CMYK, RGB-to-CMYK, CMYK-to-Multicolor and Multicolor-to-Multicolor. DeviceLink profiles thus complement the color conversions of ‘typical’ ICC output profiles and are often used for special applications in order to achieve significantly better results, for example in conversions of CMYK data for various printing processes.

ICC printer profiles are needed to create DeviceLink profiles. If you do not have printer profiles yet, you can easily create them in CoPrA (using the tool Printer Profiling from the sidebar).

Select Source and Target Profile

Select profiles

A DeviceLink profile converts colors directly from the source to the target color space in a single profile. Every color value of the source color space is therefore directly converted into a specific color value of the target color space. Source and target color space can be different or identical depending on the intended use of the DeviceLink profile. The tool DeviceLink offers the following options:

  • Source Profile: Specifies the source profile for the conversion.
  • Target profile: Sets the target profile.
  • Setting: Select one of the PREDEFINED settings (for example Proofing or Print-to-Print) or an edited setting. Predefined settings can be modified and saved.
  • Customize: Modify the DeviceLink settings to improve profile quality. Allows to specify the Rendering, the Exceptions and the Color Generation. Customized settings can be saved.

Note: All profile drop-down menus function like search fields. Simply type in some letters of the desired profile and only those profiles containing these letters will be shown in the list. To select a profile simply click on it. Alternatively you may open the drop-down menu with the little arrow on the right and select a profile from the full list as usual.

Setting: Select a suitable PREDEFINED setting for the creation of the DeviceLink profile from the drop-down menu. The names of the presets are based on typical tasks in printing.

Default: Start with this preset if none of the other presets match your requirements. Then adapt to your needs.

Default – Correction DeviceLink: Default setting for creating a Correction DeviceLink profile.

Default – Multicolor: Standard presetting, which provides a good starting point for adaptations to special requirements.

Digital Printing – Close Match: For digital prints that look as similar as possible to the source profile. Achieves the closest possible match between two color spaces, e.g. to achieve a match similar to a proof but without paper simulation and avoiding washed out shadows.

Digital Printing – PSD conformity: For digital prints according to “Fogra ProcessStandard Digital Printing”.

Digital Printing – Paper absolute: Uses a paper absolute rendering with consideration of the paper tone.

Digital Printing – Paper relative: Uses a paper relative rendering without consideration of the paper tone.

Large Format Printing – Close Match: For large format prints that look as similar as possible to the source profile. Achieves the closest possible match between two color spaces, e.g. to achieve a match similar to a proof but without paper simulation and avoiding washed out shadows.

Large Format Printing – High Saturation: Results in more saturated large format prints.

Offset-to-Gravure – Automatic exceptions: For conversion of offset data into gravure. Exceptions are determined automatically and the separation properties of the source profile are retained.

Offset-to-Gravure – Traditional: For conversion of offset data into gravure. Exceptions are predefined and the separation properties of the source profile are retained.

Print-to-Print – Automatic exceptions: For offset or newspaper printing. Exceptions are determined automatically and the separation properties of the source profile are retained.

Print-to-Print – Automatic exceptions – Paper absolute: For offset or newspaper printing. Exceptions are determined automatically and the separation properties of the source profile are retained. Uses a paper absolute rendering with consideration of the paper tone.

Print-to-Print – Automatic exceptions – Paper relative: For offset or newspaper printing. Exceptions are determined automatically and the separation properties of the source profile are retained. Uses a paper relative rendering without consideration of the paper tone.

Print-to-Print – No Black: Creates a DeviceLink profile without black separation. The exceptions are set so that no black is generated.

Print-to-Print – Traditional: For offset or newspaper printing. Exceptions are predefined and the separation properties of the source profile are retained.

Print-to-Print – Traditional – Paper absolute: For offset or newspaper printing. Exceptions are predefined and the separation properties of the source profile are retained. Uses a paper absolute rendering with consideration of the paper tone.

Print-to-Print – Traditional – Paper relative: For offset or newspaper printing. Exceptions are predefined and the separation properties of the source profile are retained. Uses a paper relative rendering without consideration of the paper tone.

Print-to-Print – Paper absolute: Uses a paper absolute rendering with consideration of the paper tone.

Print-to-Print – Paper relative: Uses a paper relative rendering without consideration of the paper tone.

Print to Print – Preserve Color Properties: For Multicolor-to-Multicolor DeviceLinks. Selects the appropriate Multicolor Mode and all other settings automatically.

White Ink + 3 Primaries – Printing on Black substrate / White Ink + 4 Primaries – Printing on Black substrate:  For color managed color prints on black substrates, such as textiles, white ink must be used first and colors must be applied on top of the white ink to obtain colorful graphics. This preset uses White for the separation. It automatically selects the appropriate Multicolor Mode  – either CMY+White_on_Black or CMYK+White_on_Black – while all other Color Generation controls are disabled.
Note: To create profiles with White, special test charts are required, which can be found in the test charts subfolder Special for the two cases CMY+White_on_Black and CMYK+White_on_Black.

Proofing: For proofing applications. The rendering intent is set to absolute colorimetric and all exceptions are disabled.

TAC300 Reduction – Same Source and Target Profile: To set the ink application reliably to 300% in your print data. Note that the source and target profiles must be identical.

Working with Profile Settings

Import, Export or Cleanup of Profile Settings

Profile settings for Printer, DeviceLink and SaveInk profiling can be selected in the drop-down menu Setting.

The package CoPrA Basic allows selection of default predefined settings. The package CoPrA M and higher provides access to all the parameters of the profile which can be customized.

To adjust these profile parameters, select Customize. Custom settings can be saved, imported and exported which provides the ability to exchange personal profiling settings easily with other CoPrA users or make them available for support purposes.

Import setting: Settings can either be imported as configuration file via the Tools menu using the entry Import setting or by dragging an ICC profile with the desired settings on the drop-down menu Setting. The name of imported profiles receives the suffix (imported). If an inappropriate profile (for example an RGB profile for CMYK profiling) is dragged on the drop-down menu Setting, an error message appears.

Export setting: Customized profile settings can be selected in the drop-down menu Setting and exported as configuration file by using the entry Export setting from the Tools menu.

However, CoPrA’s default settings cannot be exported. Standard settings are listed in the drop-down menu Setting under the entry [PREDEFINED] and can be customized, but they cannot be overwritten. After customizing any setting the name receives the suffix (edited). It is now a custom setting which is listed under the entry [EDITED] and thus can be exported. Edited settings can be saved under any name. Saved settings will be removed from [EDITED] and listed under [SAVED]. Saved and edited settings can be deleted manually.

Cleanup settings: All settings found under the entry [EDITED] will be deleted.

Sharing settings with ZePrA (CoPrA 5 and lower)

Due to the close connection between CoPrA (ColorLogic’s profiling solution) and our color server ZePrA, the profile settings from CoPrA can be used to calculate DeviceLink profiles in ZePrA.

By selecting the checkbox Share with ZePrA in CoPrA, the settings of your DeviceLink and SaveInk profiles are transferred directly to ZePrA and can be used there as SmartLink Method.

The SmartLink Method in ZePrA allows calculation of the necessary DeviceLink and/or SaveInk profiles for the conversion of PDF files on-the-fly, without the need to create these DeviceLinks in advance.

The DeviceLink tool in CoPrA: SmartLink can use the profile settings from CoPrA to create DeviceLinks in ZePrA

To do so, make all the required settings in CoPrA by entering all relevant information in the DeviceLink tool under Rendering, Exceptions, and Color GenerationClick Save As and enter a name for the setting. Confirm with OK, then activate the Share with ZePrA checkbox. 

The so created methods shared with ZePrA are then available as SmartLink Method in the drop-down menus of both the Auto Setup and the Configurations.

Note: Only saved settings can be shared with ZePrA. Default or edited presets cannot be shared.

Sharing settings with ZePrA (CoPrA 6 and higher)

The SmartLink Method in ZePrA allows to create DeviceLinks and SaveInk profiles for the conversion of PDF files on-the-fly, without the need to create these DeviceLinks in advance.
Due to the close linkage between CoPrA and ZePrA, profiling settings specified in CoPrA can be used by ZePrA to create the required profiles.

The settings are accessible via a shared folder which has the advantage that CoPrA and ZePrA do not need to be installed on the same computer. The shared folder must simply be accessible by both ZePrA and CoPrA, either over the network, a shared local folder or the cloud.

Procedure

In CoPrA

  1. Under Preferences, enable the checkbox Share CoPrA Settings with ZePrA Auto Import Folder and select ZePrA’s Auto Import folder.
    Note: The Auto Import folder must be activated in ZePrA as well.
    If the checkbox is enabled and the Preferences dialog closed with OK an information message will appear asking the user if all shared presets should now be copied to the defined Auto-Import Folder.

  2. In the DeviceLink tool, define all required settings by entering all relevant information under Rendering, Exceptions and Color Generation.
  3. Click Save As and enter a name for the setting. Confirm with OK, then activate the Share with ZePrA checkbox.
  4. CoPrA Settings created that way and shared with ZePrA are available for selection as SmartLink Method in the drop-down menus of both the Auto Setup and the Configurations settings.

Note: Only saved settings can be shared with ZePrA. Default or edited presets cannot be shared.

In ZePrA

Make sure to enable the Auto Import function in ZePrA’s Preferences and to use the same folder as CoPrA. CoPrA’s DeviceLink and SaveInk settings are now accessible in ZePrA and can be used there as a SmartLink Method. SmartLink can now create custom DeviceLinks which can be used in ZePrA configurations.

ZePrA’s Auto Import Folder
Files (such as ICC profiles, configurations, spot color libraries, gradations or SmartLink settings) that are moved or copied into the Auto Import folder are transferred to ZePrA’s internal dataset and can then be used by ZePrA.
When the file in the Auto Import folder is replaced by a newer version, it will be updated in ZePrA’s internal datasets as well.
Note: If a file in the Auto Import folder is deleted, it is not deleted in ZePrA’s internal dataset. For example if a SmartLink setting has been deleted in the Auto Import folder, it is still available in ZePrA’s internal dataset and if this setting is deleted in ZePrA’s dataset, it is still available in the Auto Import folder.

Rendering

Rendering - Overview

Every DeviceLink profile contains exactly one rendering intent. In addition to the standard rendering intents – Perceptual, Relative Colorimetric, Saturation, and Absolute Colorimetric – CoPrA offers six additional rendering intents.

Any two rendering options can be merged using a Merge slider to combine the best of both renderings. In addition, Chroma, Saturation, Lightness and the Gray Balance can be customized for all rendering intents as well. All this allows to individually adjust the rendering for a specific application.

Note: Merging rendering intents is recommended among Relative Colorimetric, Absolute Colorimetric, Blackpoint Compensation and any ColorLogic rendering intent. However, merging of Perceptual rendering and other rendering intents is not recommended for 3rd party profiles.

Gamut plot

The gamut plot illustrates a source and target gamut based on the selected Rendering settings for creating the DeviceLink profile. It is a graphical visualization of two virtual profiles with different white points and different gray balances. The source gamut white point and gray balance are assumed to be neutral in Lab and the target gamut to be a larger gamut with yellowish paper tint and yellowish gray balance. This can be seen if the Absolute Colorimetric rendering setting has been selected.

Note: The gamut plots are not based on the loaded profiles.

The plot of the Target Gamut does not change but the plot of the Source Gamut changes depending on the chosen Rendering method. If any other rendering setting than Absolute Colorimetric is selected, the white point of the source profile is matched to that of the target profile. The dotted line represents the gray balance of the Source gamut and it depends on the selected Rendering method. If a simple Relative Colorimetric rendering is selected the white points are matching but the black points are not and the gray balance is relative to the paper tint, e.g. yellowish.

For the Perceptual Rendering, there is a choice of paper-relative options such as Perceptual, Standard Compression, Blackpoint Compensation or Minimum Compression (Paper relative), or paper-absolute options such as Absolute Compression, Minimum Compression (Paper absolute) and Minimum White Compression. With all perceptual methods the white and black points are merged and synchronized between the two profiles. With paper-relative perceptual methods the gray balance is yellowish while it converges to the gray balance of the source gamut with paper-absolute perceptual methods. In our plot, for example, it is neutral.

A special feature of CoPrA’s DeviceLink module is the ability to Merge between two different rendering methods, for example, Standard Compression and Absolute Compression. The dotted lines of the gray balance and the shapes of the gamut indicate the effects when using the Merge slider.

Changes in the Advanced Rendering Options such as Saturation, Chroma, Lightness or the Gray Balance are also visible in the gamut plot. More Chroma results in a larger Source gamut and a cooler Gray Balance causes the dotted line to shift to the right to more bluish.

DeviceLink Rendering Intents

One of the most important decisions when creating a DeviceLink profile is to choose the optimal rendering settings for a given task. To simplify this decision, the Mode drop-down menu offers three modes for typical use cases in addition to a Custom mode.

 

Mode: Select between the following three typical use cases or select the Custom mode:

  1. Close Match: A typical use case is for achieving the closest possible match between two color spaces, e.g. to achieve a match similar to a proof but without paper simulation and avoiding washed out shadows. An example would be the reproduction of ISO coated V2 on a digital printing machine so that both prints should look the same.
  2. Automatic Paper Relative: A paper relative rendering without consideration of the paper tone. A typical use case would be a rather more colorful but still faithful rendering of a color space on a different printer. For example, a campaign prepared for ISO coated V2 but rendered on a large format inkjet printer without consideration of the paper tone.
  3. Automatic Paper Absolute: A paper absolute rendering with consideration of the paper tone. A typical use case would be the same as for Automatic Paper Relative, but with consideration of the paper tone.
  4. Custom: Gives full control to the user, enabling him to define all settings himself.

If one of the first three modes is selected, the two drop-down menus for the rendering methods are pre-selected with the required options, and the best fitting Merge slider setting is calculated.

In addition, the Advanced Rendering Options such as Lightness and/or Chroma are calculated as well. All options are grayed out, so the user just needs to select one of the Modes

Note: The automatic works best if the target color space has a larger or similar gamut as the source profile.

CoPrA’s DeviceLink Rendering Intents

Standard Compression: ColorLogic’s standard method, which is well suited for most applications. Neutral tones are converted using a relative colorimetric approach. If the paper white of the target profile is significantly more yellow than the source profile, the gray axis will look more yellow as well. If the target profile has a smaller color gamut than the source profile, the contrast range will be adapted to avoid a loss of image definition.

Black Point Compensation: Use Black Point Compensation to achieve the same results with a perceptive conversion as with “Relative Colorimetric with Black Point Compensation”. When converting from a large to a small color space, the image definition is preserved in the highlights and shadows, unlike with a pure Relative Colorimetric conversion. Neutral tones are converted using Relative Colorimetric. Out-of-gamut colors are cut off.

Dynamic Compression: Only available in CoPrA 6 and lower. Compares the source color space with the target color space and generates a compression that minimizes out-of-gamut areas. This setting preserves the brightness  of the original color space while reducing the saturation, and therefore also preserves the image definition. As for the Standard Compression, the gray axis of the conversion is built relative to the paper white of the target profile.

Absolute Compression: This method is based on the absolute colorimetric intent but shows some differences. The contrast range in the highlights and shadows is adapted to avoid any loss of image definition. The rendering of neutral colors is based on absolute colorimetry without paper color simulation in the highlights. If the paper white of the used printing medium is significantly more yellow than the reference, the gray axis will look neutral despite the yellowish paper white.

Minimum Compression (Paper Absolute): This method is largely similar to the absolute colorimetric intent and only compensates close to the black and the white point. Maximum shadow contrast will be achieved and image definition will be preserved while the paper white will not be simulated. Use this rendering intent if you would like to achieve a very close reproduction, for example when using print standards like ISO Coated V2 or GRACoL2006 Coated1v2 on a digital printer.

Note: As for the absolute colorimetric rendering intent, ensure that the target color space is larger or has at least a similar size to avoid any loss of image definition. For color conversions from larger to smaller color spaces use Absolute Compression to maintain the gray balance of the source color space.

Minimum Compression (Paper Relative): This method is largely similar to the relative colorimetric intent and only compensates close to the black and the white point. It is similar to Minimal Compression (Paper Absolute) but uses relative colorimetric instead.

Minimum White Compression: This method is similar to Minimum Compression (Paper Absolute). Both rendering intents compress the white point without paper simulation, however, there is an important difference: The Minimum Compression is a rather perceptual rendering that additionally compresses the black point so the maximum dynamic range is utilized without loss of detail in the shadows. In contrast, the Minimum White Compression compresses the white point but not the black point, so a close absolute colorimetric match between source and target color spaces can be achieved. This can be useful for the color representation across various media, color matching or printing on slightly differing media. It can be regarded as close to absolute colorimetric rendering without paper tint simulation.

Additional Options

Merge: Use two rendering methods, merge them in defined proportions when creating the DeviceLink profile. For instance, choose the combination Standard Compression (1st selection, left) and Absolute Compression (2nd selection, right) and set the Merge slider to 75, the corresponding proportions of the two rendering methods are used in the DeviceLink profile when converting files. In this example, 75% Absolute Compression and 25% Standard Compression results in a gray axis that is 75% adapted to the paper color, without paper color simulation in the highlights and a simultaneous adaptation of the contrast range in the highlights and shadows.

Advanced Rendering Options

Advanced Rendering Options: The drop down menu allows changes to the overall Chroma, Lightness or Saturation of the profile using a slider.

Chroma can be used to reduce or increase the chroma of highly saturated colors in the range between -20 and +20.

Saturation can be used when highly saturated colors are required. As with Chroma, the gray balance is not affected when moving the slider. Saturation or Chroma can be used especially for large color spaces such as gamut extending Multicolor in order to achieve more brilliant colors.

Advanced Rendering Options

Notes:

  1. ColorLogic intentionally keeps the chroma effect moderate. However, when increasing the chroma, ensure that the setting neither causes a loss of image definition in highly saturated colors or adversely affects colors such as skin tones.
  2. The effect of each of these settings is shown in the gamut graph on the right. Increasing the saturation results in higher chroma and lower lightness, so more saturation will slightly darken the colors and they will appear more vibrant. In contrast, more chroma can result in high chroma colors being out-of-gamut and these colors would not be rendered by the given profile.

Gray Balance: Allows adjustment of the gray balance to create a cooler or warmer gray axis. cooler shifts the gray balance towards more bluish colors (negative b* values), warmer shifts it towards yellowish colors (positive b* values). The effect of the slider setting is visualized in the graphic.

Changing the Gray Balance

Note: The setting Gray Balance works independently from the selected Rendering method which has already an effect on the gray balance and allows visual adjustments based on personal color preferences.

Modify Color Appearance with Additional Profile
Incorporate a correction into a DeviceLink profile by using an additional profile, such as an edited DeviceLink or an abstract profile. The additional profile may contain a selective color correction in a certain color range or specify a change in the gradation tonalities. The additional profile will be included in the calculation after the source profile is linked to the target profile.

The Modify color appearance with additional profile represents special situations, therefore the setting None should be selected in most cases.

Note: Further information about the creation of edited profiles can be found in the section DeviceLink Editing.

Exceptions

Automatic Exceptions

The proper choice of exceptions in DeviceLink profiling can sometimes be an art in itself and ensures hue-accurate, pure and saturated colors as well as print optimized color behavior, for example when overprinting. In order to facilitate this choice, the tab Exceptions contains an option for the automatic selection of the most appropriate exceptions for the selected source and target profiles. Here, different kinds of calculations for color rendering, color distances, device color differences as well as empirical values regarding the preservation of color purity will be combined.

To activate this function, select the mode Automatic. After a short calculation time recommended exceptions are either enabled or disabled. All automatically identified exceptions are grayed out. Exceptions that are not implicated are not grayed out and can be activated or deactivated manually. This makes it much easier to choose exceptions appropriately.

Note: We recommend enabling  the automatic selection of exceptions for the creation of DeviceLinks by default in order to obtain a good preselection. If you prefer to select exceptions manually or if you would like to adjust the automatically determined settings, select the mode Custom. If you have manually selected exceptions or a DeviceLink preset and then switch to Automatic, previous settings will be overwritten.

Custom Exceptions

Exceptions are used to specifically influence color conversions of special colors. If source and target colors in a color conversion are identical the colors will be linearized. If the color spaces differ, the colors will be optimized and adapted.

Exceptions ensure that special properties of colors remain unchanged. The choice of appropriate Exceptions thus allows a precise color conversion of specific colors. Exceptions preserve the properties of the input colors (for example using a single color channel for primary colors or two color channels for secondary colors) and calculate the best possible combination to minimize related color errors (our definition of “optimized”).

All color patches that are affected by the selected exception are highlighted in the graphical representation by a red border. If you move the mouse pointer over a color patch it is emphasized by a black or white border and the values of the source and target color space are displayed. Press the “Alt” key on your keyboard to capture the color patch allowing you to check quickly and easily whether it is affected by an exception.

Exceptions which are not available are grayed out. This may be the case when a dependency between exceptions exists, or when exceptions are not relevant for a specific color space.

Exceptions are often related to each other under certain circumstances such as Rendering or Black Generation settings. For example, if the Gray exception is enabled the 100% Black exception is enabled automatically, too. However, this is only the case if a perceptual rendering method has been selected. If a relative or absolute colorimetric rendering method has been selected these two exceptions are independent because in these cases we want to respect the colorimetric accuracy.

Custom Exception settings

Triplex (two primary colors plus black): Optimizes the color conversion of a secondary color (for example, blue: cyan plus magenta) plus black by preventing color contaminations. Triplex colors are recalculated during the conversion but remain triplex colors in the target profile. Therefore, if you have a dark shade of blue, like 100C 60M 50K, and you would like to convert it to the most suitable blue represented in the target color space consisting only of cyan, magenta and black, the exception Triplex must be activated.
The exception Triplex includes the exception Duplex and therefore also the exceptions Primaries, Secondaries, Gray and 100% Black.

Duplex (a primary color plus black): Optimizes the color conversion of a primary color (cyan, magenta or yellow) plus black by preventing color contaminations. Duplex colors are recalculated during the conversion but remain duplex colors in the target profile.
The exception Duplex includes the exceptions Primaries, Gray and 100% Black.

Gray: Protects the single-color structure of Black from 0 to 100%. This exception includes the exceptions 100% Black and White.
For RGB DeviceLink profiles Gray ensures that the gray axis is composed of equal RGB value proportions. For a conversion of an RGB source profile into a CMYK target color space, Gray ensures that the RGB gray axis is created by black only.

100% Black: Protects 100% black, so 100% K remains 100% K and will not be supplemented with or replaced by CMY.
For a conversion of an RGB source profile into a CMYK target color space 100% Black ensures that an RGB black of 0, 0, 0 is converted to 100% black. For example, this allows you to prevent a pure black RGB text from being composed of four colors in the CMYK profile after the conversion.

100% C,M,Y: Protects cyan, magenta and yellow. The 100% values of C, M and Y are retained after the color conversion at 100%.

100% R,G,B: Protects pure red, green and blue. The 100% values of red, green and blue are retained after the color conversion at 100%. Red will therefore still be formed with 100% magenta and 100% yellow.

Max. C,M,Y: Creates a maximum saturation of primaries. This function can be used independently of the protection of primaries and secondaries.
Example: If 100C would be converted to 80C + M + Y, activation of this exception ensures that cyan is now converted to the maximum value, which means, C is set to a value higher than 80, i.e. a value between 80C and 100C, depending on what is achievable in terms of maximum saturation while contaminating color proportions are adjusted color corrected.
Note: If the exception Primaries is selected as well, the exception Max. C,M,Y is grayed out while the exception 100% C,M,Y is activated instead, as in the case of a purity protection of primaries the maximum value is 100%.

Max. R,G,B: In CMYK color spaces ‘R, G, B’ corresponds to the color combinations MY, CY and CM. When activated, the higher color value is set to 100% while the second color value is optimized colorimetrically. This function can be used independently of the protection of primaries and secondaries.
Example: If a pure 100% red (100% M+Y) would be converted to 95% M and 90% Y in a conversion with pure secondary colors, activating the setting Max. R,G,B increases the color red to maximum saturation, like 100% M and 95% Y. However, if you require that 100% red remains 100% red in the conversion, use the setting 100% R,G,B.
Note, however, that this might not be the best colorimetric value.
Max R,G,B, on the other hand, calculates the best color correct value with the highest level of saturation.

Primaries: Protects the single color structure of primary colors. Calculates the Lab value of a primary color of the source profile and searches for the best matching primary color value in the target profile. For example, 40C might be converted to 53C but the single color structure remains. If this exception is not enabled, primary colors of the source profile may be contaminated in the target profile. The checkboxes C, M and Y allow protection of individual primaries. Here, optimized transitions are calculated which gently extend into adjacent color areas in order to avoid hard edges.
The slider
Tolerance allows to specify how far adjacent color areas are included.
Note: Enabling this exception does not preserve the 100% values which means that 100C might be converted to 98C. If you would like to conserve the 100% values in the target profile, enable the exception 100% C,M,Y.
In case of a conversion of an RGB source profile into a CMYK target color space, Primaries ensures that the primary colors C, M and Y are kept pure.

Adapt TVI to source profile: This exception is important when tone value increases of primary colors needs to be preserved precisely. An application example would be a predefined printing standard that needs to be printed on a different paper while the used target profile featured a different tone value increase. The exception Adapt TVI to source profile allows creation of a DeviceLink profile which corrects the tone value increases of the target profile to meet the requirements of the printing standard (from the source profile) precisely.

Secondaries: Protects the two-color structure of secondaries. Calculates the Lab value of a secondary color of the source profile and searches for the best matching secondary color value in the target profile. For example, 40C 100M might be converted to 41C 97M but the two-color structure remains. If this exception is not enabled, secondary colors of the source profile may be contaminated in the target profile. The checkboxes MY, CY and CM allow protection of individual secondaries. Here, optimized transitions are calculated which gently extend into adjacent color areas in order to avoid hard edges.
The slider
Tolerance allows to specify how far adjacent color areas are included.
In case of a conversion of an RGB source profile into a CMYK target color space, Secondaries ensures that the secondary colors MY, CY and CM are kept pure.

Black overprint: Protects 100% black as additional layer above a CMY background: CMY values are minimized but colors are calculated correctly and changed as little as possible compared to the original.

White: Protects the paper white. This is especially useful when you would like to achieve an absolute colorimetric simulation for proofs without a simulation of the paper color (e.g. for aesthetic reasons). Is available only if Absolute Colorimetric is selected as Rendering intent and Proofing as a Setting.

400% Black: Protects 400% Black: Even when a lower Total Amount of Color (TAC) is selected in the tab Color Generation, a color value of CMYK = 100%, 100%, 100%, 100% is maintained.

Border Clipping: Percentage values close to zero will be set to 0% and key values close to 100% will be rounded up to 100%. This results in pure tones which no longer need to be screened in printing.

400% Black to Pure Black: 400% inks will be converted to 100% black, so CMYK = 100%, 100%, 100%, 100% will be converted to CMYK =0%, 0%, 0%, 100%.

Highlights
In flexo printing, the first printed tone is often subject to a rather high tone value increase. Additionally, in some flexo printing processes, there is no transfer of tone values below a certain percentage in the highlight areas. However, the simulation of those process properties is particularly important for proofing applications to truly simulate the final print result in the highlights. It may also be necessary to increase the tone values in the highlights when using the profile for production or separation. For that reason, CoPrA has six settings to adjust the Highlights when creating DeviceLink profiles.

These settings specify when the First Printed Tone in the profile is recognized and appears in the proof (hard or soft proof) or how high the tone value prints at 1%. This ensures that your proof matches your printout. Analogically, when a profile is used for separation which was created with a value of 3% for the first printed tone, small tonal values will be raised to 3% to be printed reliably. By selecting a setting for the first printed tone you can determine whether the created DeviceLink is intended for Proof or Production.

Default: Ensures ‘normal’ profiling behavior in highlight areas. Use this setting for all printing processes that don’t require any adjustment of the first printed tone.

First Printed Tone (Production, Preserve 0%): The paper white remains unaffected. Small tonal values will be increased to the entered percentage to be printed more reliably. The purity of colors set in the tab Exceptions will be preserved. This may result in hard edges.

First Printed Tone (Proof): Use this setting to specify when the first printed tone will appear. For example, if you enter 3% for the first printed tone, no tonal values will be printed from 0 to 3%. Color values will start only from 3%.

Printed Tone at 1% (Proof):  This setting defines the tone value to be reached at 1%. It is popular for proofing but can be used for production applications as well.

First Printed Tone (Production, Preserve White): The paper white remains unaffected. Low tones will be increased to the entered percentage throughout the separation to be printed more reliably. The settings defined in the tab Exceptions are not retained as a tone is composed using all channels. This reduces hard edges.

First Printed Tone (Production, Minimal Tone): The paper white will be replaced by the set tonal value in all channels throughout the separation.The settings defined in the tab Exceptions are not retained as a tone is composed using all channels. This reduces hard edges.

Dependency between Gray and White exceptions in Soft Proofs
The rendering intent Absolute Colorimetric is often used in proofing in order to determine how printed colors will be affected by the color of the paper. It is important to point out that a dependency exists between the exceptions Gray and White when selecting the setting Proofing and the rendering intent Absolute Colorimetric in CoPrA.

When creating DeviceLink profiles using the rendering intent Absolute Colorimetric the simulation of the paper color will be prevented when the exception Gray is activated. The use of these exceptions in combination with the rendering intent Absolute Colorimetric is contradictory and therefore not recommended.

For this reason, all exceptions are disabled by default when the setting Proofing is selected in CoPrA. In order to make this dependency even clearer, the exceptions White and Gray are linked to each other. When an exception which is connected to Gray (e.g. Duplex or Triplex) is activated, the exception White will be disabled and grayed out automatically.

Note: Please note that the exception White is only available when Absolute Colorimetric is selected as Rendering intent. The exception White ensures that paper white is not simulated which is especially useful when trying to achieve an absolute colorimetric simulation for proofs without a simulation of the paper color (e.g. for aesthetic reasons).

Color Generation

Color Generation

Multicolor Mode: Determines how colors will be built up in individual separations. Is only available when a Multicolor target profile has been loaded. A Multicolor license is required to use Multicolor features.

Note: Multicolor modes that are not recommended for the loaded measurement data are marked red in the drop-down menu.

In some cases a warning or information message is shown below at the bottom of the window in case the loaded data may require a different mode than the selected one.

In CoPrA, the first three channels represent primary colors (usually CMY). They should form a sound color space (gamut) and should also be able to create a gray axis. The fourth channel should be black if a separation with UCR/GCR is desired. If black is absent in the Multicolor measurement data while automatic Black Calculation is selected, it will be recognized by CoPrA and the separation will not be generated. Black separation is disabled if the value for Max. Black in the Black Point and TAC setting is 0%. Additional spot color channels (e.g. Orange, Green or Violet in a CMYK-OGV 7 color data set) are regarded as color space expanding colors. The Multicolor Mode determines how color space expanding colors are factored in together with primary colors.

Color Generation options

The following Mulicolor modes are available:

Multicolor modes

Strong: As much spot color as possible will be applied. Accordingly, fewer primaries will be used in the highly saturated color areas. This results in a greater use of color space expanding spot colors and therefore in highly saturated colors in the printout.

Smooth: Use this method when more CMY is required and if a particularly smooth and harmonious separation with the extended colors is needed.
Note: The two Multicolor modes Smooth and Strong are similar but Smooth uses less color space expanding spot color channels.

Smooth – with special colors and Strong – with special colors: These two Multicolor modes are designed for applications in industrial printing, such as ceramic printing, in which the main colors are supplemented by additional light (e.g. Pink) or dark (e.g. Brown) color space expanding colors. They are an enhancement of the existing Multicolor modes Smooth and Strong, however, they also use additional colors that are not commonly used. For example, the additional color pink is used with a darker magenta in magenta gradations. Here, pink is used in light areas while magenta is used in dark areas.

Notes:

  1. The gray balance of these two Multicolor modes shows additional channels as bright or dark colors are incorporated into the gradations and gray balance curves.
  2. These two Multicolor modes also support light inks in profiling, such as light and dark magenta. In principle, light and dark colors should be processed in the printer or RIP (Raster Image Processor). If they are not pre-processed by the RIP they require particularly large test charts for profiling.
  3. It is also possible to combine light gray with black which in some printing processes like Flexo printing can mask noticeable artifacts in the highlights. However, appropriate test charts have to be used.

Generate separations with sparse inks: Is of interest for the packaging market as color separations are created in such a way that a certain hue uses as much as possible of a related spot color and very little or no primary colors. For example, in order to create a red color as much as possible of a reddish spot color is used but very little to no magenta or yellow. A maximum of two or three colors are used for each color segment and, therefore, this Multicolor mode is practical to save process colors. However, black generation cannot be controlled and is based on the (separation) mode MaxK.
Note: In contrast to the Multicolor modes Smooth, Strong and Use CMYK only, the Multicolor mode Generate separations with sparse inks does not allow regulation of the Black Generation. Accordingly, these settings are grayed out.

Use CMYK only: Selecting this method results in a Multicolor DeviceLink profile that creates the desired number of channels (e.g. 7 channels) but is only composed of CMYK. The color space expanding spot color channels are not used for the separation.

Notes:

  1. In package printing there is sometimes a request for images and vectors composed of CMYK to be generated with only minimal changes to CMYK values and without spot colors – despite conversion into a Multicolor space. In this case, only spot colors, like Pantone colors, which are present as DeviceN in the PDF should be converted into the large Multicolor space. Such a workflow is possible in two easy steps: (1) Creation of a separation-preserving CMYK-to-Multicolor DeviceLink profile in CoPrA using the Multicolor method Use CMYK only. (2) Spot color conversion of the PDF using ColorLogic’s color server ZePrA.
  2. In CoPrA all setting concerning the Color Generation (i.e. the entire tab) depend on black being present in the measurement data. This also applies for Exceptions. All Exceptions concerning black (Gray, Black, Duplex, Triplex, Black overprint) use black as fourth channel, therefore, black must be present in the measurement data or ICC profiles as fourth channel. If black is not present in the measurement data as fourth channel, this channel will be treated as if it were the black channel.
    As an example, if blue is present as fourth channel, then all settings in the tabs
    Color Generation and Exceptions will still treat the fourth – now blue – channel as black channel. In this situation, spot colors can be used for the calculation of the gray balance and the black point.

Preserve Color Properties: Is only available for Multicolor-to-Multicolor DeviceLink profiles. This Multicolor Mode allows the use of Exceptions for all Multicolor channels (not only for CMYK) thus preserving pure colors and the separation characteristics of the source.
All types of Multicolor-to-Multicolor combinations can be applied. Source and target color spaces can differ in their number of channels (e.g. for 6 to 7 color DeviceLinks), in their hue, or in their name.
Channels that are similar in hue are automatically assigned even if the channel names or the channel order differ between source and target profiles. If single channels do not match between source and target profiles but other channels do, the matching channels will be retained while the non-matching channels are recalculated using a mixture of the other channels to match the colors of the original channel. 

Example: When combining a CMYKOB profile with a CMYKOGV profile, the Orange channel (O) will be retained but the Blue channel (B) will be recalculated using Violet (V) and a mixture of the other primaries to match the Blue original colors.

Note: Exceptions for Primaries affect all channels. The exceptions for Secondaries keeps all two color combinations pure, not only those with CMY portions.

Use Settings of the Target Profile: Uses the Multicolor mode that was selected when the printer profile was created. The used mode is written in parentheses. That way it is immediately clear which mode was used in the profile.
Note: Only applies to CoPrA printer profiles. For non CoPrA Multicolor profiles the Strong Multicolor mode will be used.

CMY+White: If the measurement data includes White as a color channel in addition to 3 primary colors,  Multicolor Mode must be selected. CMY refers to any 3 primary colors that form a sound color space and include a gray balance. This mode predefines the separation settings to use the color of the background (e.g. the black substrate) and the white ink within the separation. It automatically selects the optimal settings, therefore, all other Color Generation controls are disabled, only the overall TAC can be adjusted under Black Point and TAC.
Please be aware that the resulting ICC profile is a Multicolor profile (4CLR profile).

CMYK+White: If the measurement data includes White as a color channel in addition to Black and 3 primary colors, this Multicolor Mode must be selected. CMY refers to any 3 primary colors that form a sound color space and include a gray balance. This mode predefines the separation settings to use the color of the background (e.g. the black substrate) and the white ink within the separation. It automatically selects the optimal settings, therefore, all other Color Generation controls are disabled, only the overall TAC can be adjusted under Black Point and TAC. The assumed black point, e.g. the darkest color, uses a predefined combination of 100% Black printed on the back substrate.
Please be aware that the resulting ICC profile is a Multicolor profile (5CLR profile).

Background: For color managed color prints on black substrates, such as textiles, white ink must be used first and colors must be applied on top of the white ink to obtain colorful graphics.
Note: To create profiles with White, special test charts are required, which can be found in the test charts subfolder Special for the two cases CMY+White_on_Black and CMYK+White_on_Black.

Black Generation

Defines the method for the generation of black in the target color space and therefore influences the separation comprehensively. Nine different black generation modes are available in the drop-down menu (depending on the licensed modules):

Target Profile: Uses the black separation and the out-of-gamut mapping of the target profile. Denies modifying the Color Generation and Black Point and TAC settings.

Target Profile with ColorLogic Gamut Mapping: Uses the black separation of the target profile – same as Target Profile – but recalculates the out-of-gamut mapping. Allows to change the Black Point and TAC settings. After clicking Modify the black generation settings can be changed as well. This way the settings of the target profile act as a starting point and can then be adapted to your needs.
Note: When clicking Modify the black generation switches to an appropriate mode closest to the target profiles settings (GCR, UCR, maxK…). This works best for ColorLogic printer profiles as the appropriate settings are exactly reproducible. For 3rd party profiles this may lead to a little update of the curves as with some profiles only settings as close as possible to those of the 3rd party profile will be found.

UCR: Allows adjustment of the settings Black Start and Black Width.

GCR: Additionally allows the adjustment of the setting GCR Amount.

MinK: Only uses a minimal amount of black and generates a separation using the maximum amount of CMY.

MaxK: Uses a maximal amount of black and generates a separation using the minimum amount of CMY. Is only available with a SaveInk license.

The methods UCR, GCR, MinK and MaxK generate a new separation, regardless of the separation of the target profile.

Preserve Separation: Preserves the ratio between the black channel and CMY composed black.
Note: The black generation mode Preserve Separation is especially important for conversions between similar CMYK printing processes (conversions between two offset presses or two inkjets of the same model etc.), because it ensures that the ratio between CMY and black which is used to generate gray is maintained in the color conversion.
When the mode Preserve Separation is selected, Enhance Shadows should always be enabled.

Preserve Black: Linearizes the black value of the source profile and retains the black channel.

Save Ink: Replaces CMY colors by black to save CMY inks. This setting is only available with a SaveInk license.

Preserve 0% Black: Is available when the mode Preserve Separation has been selected. It prevents the generation of a black channel in source colors without black. This is important for some overprint applications.

Enhance Shadows: Is also only available when the mode Preserve Separation has been selected. Prevents detail losses in dark colors and weak shadows.

GCR Amount: Defines the amount of CMY that is replaced by black. At 0 only a low GCR amount is used which mainly impacts the shadows whereas at 100 a very strong GCR is used which effects the shadows and the highlights.
Black Start: Defines the starting point for the black generation. Black will be used if the minimum amount of C, M, Y exceeds this limit.

Black Width: Defines the range in which black is generated outside the color-neutral area. The lower the value the less black will be generated outside the color-neutral area.

Ink-Saving: Replaces CMY colors by black to save CMY inks. This setting is only available with a SaveInk license (included in CoPrA XL and CoPrA XXL) and if the Save Ink option was selected under Black Generation.

Black Control Range: Controls the transition to black. If black exceeds the limit, CMY colorants will not be modified and black is linearly added. Up to the specified value black will be calculated accurately. A value of 0% indicates that only CMY will be converted whereas black will be linearized. If a proof requires an exact colorimetric reproduction the slider should be set to 100%. 80% is a good value to achieve a smooth transition in the shadows. We recommend to activate the checkbox Auto.

Used Channels: Defines the channels to be used in a profile and offers a quick and easy way to select or exclude channels when separating data. The effect of selecting or excluding colors on the curves is immediately visualized in the Graphic.
Note: If the Black Calculation is set to Target Profile, the black point is preset by the profile and the function Used Channels is deactivated.

By default all colors of the profile are enabled. To exclude a color click on the appropriate colored box. Multiple colors can be excluded. Excluded colors will be grayed out and marked with an X. To enable an excluded color simply click on it again.

Note: This function is particularly intelligent for Multicolor profiles, as it searches for replacement colors in the Multicolor channels when excluding a channel (e.g. Cyan), which can compensate for the missing channel in the gray balance. The alternatively calculated Multicolor channels are displayed grayed out in the panel Black Point and TAC (further information can be found in the toggle Black Point and TAC).

Example: If a brown chocolate artwork is intended to be printed in CMYK without using any Cyan in the separation, a CMYK printer profile can be created which only uses MYK. These types of profiles avoid unwanted Cyan dots in the separation and the converted artwork would appear visually close to a conversion with a complete CMYK profile. Obviously such a profile should not be used if the artwork contains Cyan based color combinations, such as cyan tones and blue or violet colors.

Avoid Dot-on-Dot: Prevents Black and Violet/Blue color combinations that could produce dot-on-dot effects in AM printing. Replaces some of the Black by CMY, therefore avoiding dot-on-dot effects.

Background: When using gamut extending process colors in traditional AM screening, such as CMYK+Orange+Green+Violet/Blue, the process colors Violet or Blue are often on the same screening angle as Black which can cause dot-on-dot issues leading to color and lightness variances. However, avoiding Black and Violet/Blue color combinations in separations would reduce the available gamut considerably and would also prevent dark bluish spot colors from being reproduced faithfully. By activating this feature the separation uses more of the CMY colors instead of Black thereby preventing dot-on-dot effects. For this function to work best, use a late Black Start and a rather weak GCR or even a UCR Black Generation setting.

Note: Other color combinations using the same AM screening angles such as Cyan and Orange or Magenta and Green are not affected by this feature as those combinations are rarely used in separations anyway.

Graphic: Visualizes the effects of the selected color separation and Black Point settings. Provides a real time preview of the loaded measurement data when altering settings.

Black Point and TAC

In the panel Black Point and TAC you can define the overall Total Area Coverage (TAC) and the TAC for the black point (Black TAC). The black TAC represents the darkest color value of the profile which is usually identical with the maximum TAC. The graphical display of each color contains a number field showing the amount of ink used in the profile. Depending on the selected Black Calculation the number fields are either enabled or disabled.

Note: The default window size sometimes truncates the input fields for Multicolor channels. Enlarge the window to display the input fields for all colors.

Black Calculation: Five different settings available for DeviceLink profiling (see screenshot below).


Black Calculation methods

Auto: The calculation of the optimal black point (dark and neutral) is based on the target profile. The values entered for Black TAC and Max.Black define limits which are not exceeded but may be lower if technically possible. All channels are used to generate the black point (Black TAC), therefore individual channel editing is disabled. This mode will not use any Multicolor channels beside the first four channels (usually CMYK).
Note: If no default value for the Black TAC is defined, it is recommended to use 400% as a starting point for the calculation.

Balance CMY: This setting adapts the CMY values to a pre-defined Max.Black value and generates a neutral black point. Define the Black TAC and TAC in accordance with the printing conditions. The Max.Black should be set to the ideal value for your substrate. Similar to the setting Auto those values are regarded as maximum values which may be underrun if a neutral black point is not achievable. Allows customization of the black channel (or in general the 4th channel) and the addition of Multicolor channels.

Note on excluding channels: Basically Balance CMY allows editing of the black channel (or in general the fourth channel) and the Multicolor channels. The CMY channels are grayed out (see screenshot).

However, if a channel is excluded, the Multicolor channels are searched for a replacement color that can compensate for the missing channel in the gray balance. The replacement Multicolor channels are grayed out in the control panel Black Point and TAC (see screenshot).

Darkest: Calculates the darkest possible black point with maximum density/lowest L*. Allows generation of a black point without neutral a* and b* values and darker L* if available.

The values entered for Black TAC and Max.Black define limits which are not exceeded but may be lower if technically possible. Darkest uses the first 4 channels, usually CMYK. Possible multicolor channels are not considered, but can be used and changed manually if necessary (same as with the option Balance CMY).

Custom: Allows to define the black point in the input box Custom as CMYK values. The Black TAC value will then be recalculated. Allows editing of all channels.

Notes:

  • CoPrA calculates the Lab values based on the entered custom values. When changing custom values the resulting effects can be seen immediately. If you prefer CoPrA’s recommendations select the settings Balance CMY or Auto.
  • For Multicolor profiles with more than four channels you can use the extra Multicolor channels for the black generation besides the first four channels (typically CMYK). However, the total area coverage (TAC) cannot exceed 400%. Values for the Multicolor channels can be entered manually when using the settings  Balance CMY or Auto and these values will then be used to calculate the Black TAC. Usually it is not necessary to use those channels but sometimes a dark Multicolor channel adds desired contrast and definition. This can easily be checked by viewing the Lab values below the Custom fields. If the addition of a certain Multicolor channel decreases L* while a*b* values are not significantly altered, using this channel can be considered. However, the gray balance will use additional channels as well.

Note: Neutral a* and b* values are the basis of the Black Calculation when selecting the settings Auto or Balance CMY. In contrast, selecting the setting Custom allows generation of  a black point without neutral a* and b* values.

Target Profile: Calculates a black point based on the values of the target profile. The values for the calculation will be displayed and all sliders will be grayed out.

Total Area Coverage (TAC) and Black TAC
Many modern printing systems allow a black point that is generated by using a low amount of ink. Sometimes the darkest color can be printed using pure black which means in extreme cases a black point of 100% K may be sufficient. Obviously, such a low TAC does not work for other color areas – it would not even be possible to print a true red, green or blue! Therefore we separated the Black TAC from the general TAC. This allows use of the best setting for Black Calculation without restricting the color space.

TAC: Defines the value for the maximum total area coverage (value range: 0 to 400%). This value will not be exceeded. This also applies to Multicolor profiles. The TAC can also be set for 2 or 3 channel profiles.
Note: The sliders limit each other, so the TAC can never be lower than the Black TAC (but it can be higher).

Black TAC: The Black TAC is the sum of all color values. The value resulting from your settings for the black point (Black TAC) is displayed after a short calculation under the Custom text field next to the calculated Lab value in percent (red frame in the screenshot below).

The Lab value is particularly handy for assessing the effect on the black point when changing the TAC or Black TAC. The smaller the L* value, the deeper the black and the higher the contrast.

Max.Black: Here you specify the maximum amount of black ink to be used by the separation (value range: 0 to 100%). Note that the entered value always refers to the fourth channel which, in Multicolor cases, may not be black but a chromatic color. Furthermore, the fourth channel of the Black TAC is always used for the darkest point of the profile, the black point.

TAC and Black TAC can be adjusted separately in CoPrA
The total area coverage (TAC), defined by the separation, and the black TAC are identical in traditional printing systems, however, industrial printing applications and many digital printing systems show that the black point can be selected much lower than the total area coverage. To achieve a sound gray balance with a high contrast while maintaining highly saturated colors it is necessary to separate these two settings.

Advantages of a separate Black TAC
The importance of adjusting the Black TAC independently from the total area coverage (TAC) is demonstrated using a digital printing system. Let’s assume the Black TAC and the TAC could not be set separately and we had to use identical values for both of them. If you selected the mode Auto to calculate the black point and set a TAC of 300% (and therefore a Black TAC of 300% as well), CoPrA would calculate the best black point for this case. The result would be a total area coverage of 275% with a neutral black point (a* and b* are 0 respectively), but with a very light L* of 22.0 (outlined in red in the screenshot).

However, CoPrA allows to set the Black TAC separately from the total area coverage (TAC). As pure black is used in some digital printing systems as the darkest printing color, the Black TAC can be reduced to 100% which results in a black point with a significantly darker (lower) L* value of 9.8. Using a separate setting for the Black TAC achieves a significantly higher and better contrast than a TAC which is linked to a Black TAC of 275%. Additionally, a total area coverage (TAC) of 300% ensures highly saturated colors. These precise settings are only possible with separate TAC values.

Profile Processing

Format, Size and Further Processing

In the last step of profile creation, assign a Name and choose the Format and Size of the profile (see screenshot).

Name: Type in a Name for the profile.

Templates: Allows to select and combine name components from a list of options and save them as custom templates. The last selected template is used when creating new profiles, so the naming of profiles is automated.
Available naming options depend on the current profile type and include Date, Date/Time, Measurement data file name, Source and Target profiles, Name of the current preset and others. Each name component can be added at a user-defined position under Template (the position is selected with the mouse pointer). The Example section below shows the resulting name. Additionally, user defined text can be added at any position within the Template field.

Format: Define the Format of your profile. An ICC format in accordance with specification v2 is recommended as basic setting however, the newer format ICC v4 can also be chosen. In this case, please ensure that your programs support this format.
Note: ColorLogic products handle and use ICC v4 profiles consistently and correctly.

Size: The setting Large is recommended. The size specifies the number of grid points in the profile and determines the amount of disk space required for the generated profile. Small profiles should only be used for test purposes. Very Large profiles can slow down further processing in subsequent programs. Additionally, some programs are not able to handle very large profiles.

Further processing

Create Profile Report (PDF): Recommended to activate. The PDF report provides an overview of the quality of the profile based on statistics, diagrams of gray balances, gradients and gamut representations as well as color separations of converted test files.

Save Preview Profile: Is only available in Multicolor printer profiling. By activating this checkbox an ICC preview profile will be created in addition to the printer profile. It can be used as a soft proof profile in Adobe Photoshop.
Notes: Preview profiles are only suitable for proofing purposes. Either a preview profile or a CMYK profile can be created in one profiling step, but not both.

Embed profiles: Physically incorporates the used source and target profiles into the DeviceLink. This function is tricky and only recommended if the DeviceLink has to be transferred to a computer which does not have the required source and target profiles. It was implemented mainly for use with certain RIPs which only accept DeviceLinks with embedded source and target profiles.

Save: Creates the printer profile and saves it in the folder Profiles (macOS) or Color (Windows), (macOS: /Users/Username/Library/ColorSync/Profiles, Windows: C:\\Windows\\System32\\spool\\drivers\\color). Demo and encrypted profiles will be saved in a different location only relevant for ColorLogic applications.

Note: CoPrA-SP profiles are stored in the ColorLogic subfolder Licensed-Profiles.

Preview Profiles

Introduction: Using Preview Profiles for Soft Proofs

Preview profiles allow soft proofing of image files in DeviceLink profiling and Multicolor printer profiling, without converting a file. Multicolor preview profiles provide a true color representation of images to be converted into the Multicolor color space in order to review the achievable result prior to the actual Multicolor conversion (More information can be found further down in the text). The same applies to DeviceLink conversions. Here, too, the DeviceLink preview profile can be used in Photoshop with the original data to visually review how the result of such a conversion would look like.

Preview profiles can be created together with DeviceLink or Multicolor printer profiles by activating the checkbox Save Preview Profile (see screenshots). Preview profiles have the suffix ‘preview‘ and are saved in the folder Profiles (macOS) or color (Windows), (macOS: /Users/Username/Library/ColorSync/Profiles, Windows: C:\Windows\System32\spool\drivers\color). Right clicking on the preview profile and selecting the menu entry Show file in the context menu will take you directly to the location of the selected profile.

Creating preview profiles in Multicolor printer profiling.

Creating preview profiles in DeviceLink profiling.

A preview profile is a printer profile with the same color space as the source profile of the DeviceLink. It can be used as soft proof profile, for example in Adobe Photoshop. Preview profiles can be created for the following DeviceLink combinations:
RGB-to-CMYK, CMYK-to-CMYK, RGB-to-Multicolor and CMYK-to-Multicolor

Note: The creation of preview profiles is not available for DeviceLink profiles using more than four channels in the source color space since only preview profiles of the color spaces Gray, RGB or CMYK can be used in Photoshop. Multicolor printer profiles are not affected as their preview profiles are always RGB profiles which can be used in Photoshop.

Example: To adapt your RGB image data in RGB mode to the desired CMYK printing condition, use the preview profile of your RGB-to-CMYK DeviceLink as soft proof profile in Adobe Photoshop to check how the image would look like after the conversion. This allows specific RGB adjustments without the need to convert the RGB file early on. A preview profile is a very useful feature, particularly in view of storing RGB image data in media-neutral workflows.

Preview profiles can also be created for Multicolor printer profiles which allows a true color simulation of the color representation prior to application of the Multicolor profile. Although Adobe Photoshop CS4 or higher is able to convert image data using Multicolor profiles, the display of multichannel files is not a true color representation in Photoshop. So far, a true color representation of multichannel files is only possible using additional plug-ins and causes an increased workload. The preview profile function generates an RGB printer profile which features the same color visualization as the original Multicolor profile. Use this preview profile on an original image data for soft proofing.

Note: Preview profiles are only intended for soft proofs and should never be used for the actual conversion. A preview profile provides an excellent visual preview of the expected result of a DeviceLink conversion. However, the special features of the DeviceLink, such as preserving color purity, cannot be 100% emulated.

Using Preview Profiles for DeviceLinks in Adobe Photoshop

  1. Open the original image data to be converted using a DeviceLink profile in Adobe Photoshop.
  2. Either assign the Preview profile from CoPrA to this image file, or select the Preview profile in the dialog Customize Proof Condition as Device to Simulate (see screenshot).
    Note: The color space of the preview profile is based on the color space of the DeviceLink’s source profile. It is an RGB preview profile for RGB-to-CMYK DeviceLinks and a CMYK preview profile for CMYK-to-CMYK DeviceLinks.
  3. Click Preserve CMYK Numbers to get a virtually exact preview of the expected color representation for the DeviceLink conversion.
    Note: Pipette values do not correspond to the final DeviceLink conversion. Only the color representation in the soft proof does.

Using Multicolor Preview Profiles in Photoshop

  1. Open the original image data to be converted using a Multicolor printer profile in Adobe Photoshop (for example an RGB image).
  2. Select the Preview profile from CoPrA in the dialog Customize Proof Condition as Device to Simulate. Find the profile in the list of RGB profiles. The naming is based on the Multicolor profile name: Profile name_preview.icc
  3. Select the desired Rendering Intent and disable the checkbox Preserve RGB/CMYK Numbers.
    Note: Eyedropper values do not correspond to the final DeviceLink conversion. This is only for a soft proof.
Profile Reports

Profile reports can be created for Printer or DeviceLink profiles. To do so, activate the checkbox Create Profile Report in the last step of the profiling or, when updating profiles, the checkbox Create Profile Comparison Report.

Depending on the type of profile the report contains various statistical data, such as statistics about profile precision (Integrity, Precision, Black Point, White Point etc.), graphic representations of curves and gamuts (Gray Balance, Gradients etc.), conversions of test images, separations and color patches to evaluate the smoothness or the purity of colors. All this facilitates the detection of artifacts that may be present.

Profile reports can be created at any time in Batch Overview or in Profile Manager which, by the way, is not restricted to ColorLogic profiles.

Under Preferences you can define some basic settings for the creation of the profile report, such as the file location, the report format (PDF or XML) or the DeltaE method (dE76 or dE2000).

Note: If a profile comparison report is created when updating a profile, the measurement data obtained from the update test chart will be compared to the data of the original profile (reference profile).

If the checkboxes Brightener Compensation or Measurement Correction have been activated, the data of the original profile will not be compared to the measurement data from the update test chart but to the data modified by these options.