ZePrA | Screen Preview

Screen Preview

Previewing PDF and image files

Previewing PDF and image files

ZePrA’s Screen Preview displays a true color representation of files processed via queues on the monitor, with overprinting elements and transparency effects displayed correctly.

The Screen Preview uses a rasterized version of the processed file.

ZePrA is among the very few PDF and image preview applications that allow a true color preview of PDF and image files with Multicolor profiles.

Typically, jobs processed by ZePrA contain the target color space embedded as output intent. The Screen Preview automatically uses that profile and the monitor profile set in the operating system preferences for display. If no profile is embedded, ZePrA uses the target profile of the configuration used to process the file as the Simulation Profile. This allows a potentially true-color preview of files (provided the monitor is calibrated correctly).

How to display a Screen Preview

  1. Open the Overview from the sidebar.
  2. Right-click a job in Processed Jobs to open the context menu.
  3. Choose Screen Preview.

  4. Your file will open in a new window.

  5. Click on the colored symbol in the title bar to open the Screen Preview Color Management Settings.
    Select the desired Simulation Profile from the drop-down menu and the rendering intent with a checkbox for the preview of the image (only profiles that fit the color space of the loaded image are available).
    If the configuration has the target profile embedded as output intent this will be shown in the drop-down menu with the key word Output Intent and if the target profile is not set to be embedded the key word is Target Profile. In both cases, the corresponding profile from the configuration is selected and shown in brackets.
    If the checkbox Paper White Simulation is selected, the absolute colorimetric rendering intent is used, if the checkbox is deselected, the relative colorimetric rendering intent is used.
  6. Click Apply to view the selected file with these settings and Save to save and close the window with these settings. The next time you open the window, these settings will be used again.

    Note: In general, it is recommended to use a dimmable standard light box with a reference proof next to the monitor for visual comparison when selecting the correct screen preview intent.

Screen Preview Settings ZePrA 9 and lower

Simulation Profile: The colors are rendered to the monitor profile using the selected simulation profile. By default, the output intent that was embedded into the processed file by ZePrA is used. It is displayed in brackets. This setting is similar to the output preview of Adobe Acrobat.

Note: The Default Profiles and the checkbox Prefer embedded Profiles are only relevant if the Simulation Profile differs from the color space of the file.

Rendering Intent: A color conversion method (rendering intent) must be selected for the calculation. In addition to the standard ICC-Intents, there are four extra ColorLogic intents:

  • Black Compensation
  • Relative+ and Absolute+: Only have an effect if the black point in a matrix monitor profile is lighter than L* = 0, which makes the Screen Preview slightly darker, especially in the shadows, which usually results in a visually better match with a reference proof.
  • Relative Lightness: Is based on the Absolute Colorimetric intent with paper tone simulation. The brightness of the paper tone simulation is scaled to the maximum displayable brightness of the monitor, whereby the colorfulness of the paper tone simulation and the gray balance of the preview as a whole are preserved. This setting is useful if the absolute colorimetric preview provides a visually too dark display, as is often the case in newspaper printing.

If no simulation profile is available in the file (no profile is shown in brackets), select the appropriate profile from the drop-down list. Suitable rendering intents here are the colorimetrically based and the special ColorLogic intents.

The monitor profile stored in your system is automatically selected to display the screen preview on your monitor.

Click Apply to view the selected file with these settings and Save to save and close the window with these settings. The next time you open the window, these settings will be used again.

Note: In general, it is recommended to use a dimmable standard light box with a reference proof next to the monitor for visual comparison when selecting the correct screen preview intent.

Use of Multicolor profiles

Multicolor Profiles

Use of Multicolor profiles

ZePrA supports the use of Multicolor printer profiles and Multicolor DeviceLink profiles (RGB-to-Multicolor, CMYK-to-Multicolor and Multicolor-to-Multicolor).

Use of Multicolor profiles in PDF workflows

In ZePrA, Multicolor profiles can be used as document color space, as target profile or Multicolor DeviceLink profile for color conversion.

This is particularly important in the prepress stage for packaging printing when image data is available as RGB or CMYK files. You can therefore place RGB and CMYK image files directly in the finished document, create a PDF file from them and then convert this document in ZePrA to the required Multicolor color scheme for printing. Another interesting field of application is the printing of photo books in so-called Hifi-Color printing processes using 6 or 7 inks.

Note: A Multicolor license is required to use the Multicolor functions.

When preparing the data, ZePrA generates a so-called DeviceN PDF file in which each individual channel is named after the channel names of the Multicolor target profile. DeviceN has been the standard color definition within PDF for many years to describe spot colors for print production. This provides a high degree of compatibility with the proven spot color processing of common applications. The generated PDF files can usually be evaluated with current versions, for example of Adobe Acrobat Professional, in the separation preview and can be processed with current PDF workflow systems. It is also possible to place PDF files into and export them from current Adobe InDesign documents. ZePrA supports the PDF/X-5n standard, which enables the embedding of Multicolor profiles in PDF files.

By default, a configuration created with Auto Setup does not embed the Multicolor target profile in image data, but in the Output Intent of PDF files. In the case of a converted PDF/X file (for example, a PDF/X-4, -X-3, or -X-1a file), the color converted file is converted to a PDF/X-5n file.

Before using a Multicolor printer profile that you select as target color space in the Document/Target tab of the Configurations tool, or in case of a Multicolor DeviceLink profile, check that the channel names and Lab color definitions have been entered according to your specifications.

If the checkbox Embed into Output File is activated, ZePrA transfers the channel names and color definitions from the Multicolor printer profile selected as the target color space to the color converted PDF file.

If this checkbox is not activated, the channel names and color definitions are taken from the Multicolor DeviceLink profile. So make sure that the channel names and Lab color definitions in the target profile and DeviceLink profile are identical. The names of the color channels (Colorants) and the Lab color definitions can be adapted in CoPrA with the Profile Manager for each Multicolor printer and DeviceLink profile according to your specifications.

Depending on the used Multicolor profile, the contained channel designations and the subsequent workflow outside of ZePrA, we recommend that tests of the complete workflow be carried out in advance to ensure that everything runs smoothly.

Convert image data with Multicolor profiles

ZePrA supports PSB, PSD, TIFF and JPEG files when converting image data with Multicolor profiles. Since the current file format specifications (as of May 2019) do not support embedding Multicolor profiles in TIFF, JPEG, PSB and PSD files, you should disable profile embedding for image data conversion in the Document/Target tab. We recommend saving image data converted to Multicolor as PSB or PSD files in Photoshop and then processing them with ZePrA. Of course you can also place PSB and PSD image files converted with Multicolor target profiles by ZePrA in Adobe InDesign.

ZePrA distinguishes between the following cases when converting image data from Multicolor files (can be set under Configurations/Options/Image quality):

  • If the channel names of the Multicolor target profile are CMYK+X, a TIFF file will be generated provided that Preferred lossless Format is set to TIFF.
  • If the channel names of the Multicolor target profile are not CMYK, a PSD file is created.
    Note: TIFF only supports CMYK+X.
  • If the Compression Method is set to Automatic, an attempt is made to preserve the format or to generate a TIFF file. However, if a JPEG file or a non-CMYK Multicolor profile is present, a PSD file is created.
    Note: JPEG generally does not support Multicolor color spaces.

ZePrA and PDF Preflighting

ZePrA and PDF preflight

PDF-Preflight

Check the following aspects regarding color with a PDF preflight:

Check number and type of color channels present in the PDF file

Extra spot colors may be required or unnecessary depending on the print job. The preflight allows you to determine whether the number and labeling of the color channels are appropriate for the print job.

Undefined spot colors can be processed using ZePrA’s spot color module. If the spot color module has not been licensed, spot colors can at least be converted using the alternate color space (PDF). This provides the same results as a preflight program. Further information on the spot color module can be found in the Spot Color Processing chapter.

Once the job has been processed in ZePrA, the spot colors occurring in the PDF file can be checked by right-clicking on the processed job in the Overview to open the context menu and selecting Show Job Properties to open the Job Report. This is particularly useful when not using an additional preflight program.

Check RGB or CMYK objects containing embedded profiles

For fully automated workflows that are running without additional approval by the customer, we recommend printers only accept pure CMYK PDF files that have correctly embedded profiles. For other data, we recommend to optimize them with ZePrA and then send a low-res CMYK soft proof to the customer for approval.

Note: A standard queue created with Auto Setup (Normalize and convert Colors to new Output Condition) that uses the SmartLink function optimizes all RGB, CMYK, and Gray objects of a PDF file by using DeviceLink profiles. Any embedded profiles are taken into account in the conversion. Alternatively, a standard queue can be duplicated to change the handling of embedded profiles (see next section Ignoring CMYK Objects with Embedded Profiles).

The profiles embedded in the PDF file can be checked after job processing by right-clicking on the processed job in the Overview to open the context menu and selecting Show Job Properties to open the Job Report.

Ignoring CMYK objects with embedded profiles

In some workflows, especially in print shops, it is common to remove embedded profiles from CMYK objects (images and vectors). It is often assumed that the profiles have been added incorrectly and will cause problems in a subsequent ICC conversion.

When the SmartLink function is not licensed, this procedure follows the default setting for Auto Setup queues. When the SmartLink function is licensed, embedded profiles are taken into account. SmartLink conversions, which preserve primary and secondary colors, as well as separation, ensure clean conversions.

If embedded profiles are to be ignored or the SmartLink function is not to be used – for example, in Auto Setup queues for normalizing and color conversion or for SaveInk applications – deactivate the corresponding checkboxes (Apply Embedded Profiles/Intents or Apply SmartLink) in the Images/Vectors tab. This ensures that embedded CMYK profiles are not used. Instead, select Same as Document Color Space and convert with the profiles set in the Document/Target tab.

Check the maximum Total Area Coverage (TAC)

For print shops, it is important that the specifications for the data delivery and the order confirmation clearly indicate the maximum Total Area Coverage that is expected for the type of paper to be used and also the printing standard the client should prepare the printing data.

When printing on newspaper or uncoated paper and the maximum Total Area Coverage is significantly exceeded, this indicates that image data has not been optimized for the respective printing standard. Usually these are image data for coated paper in offset printing.

When optimizing PDF files via standard queues in ZePrA, the following alternatives are available in Auto Setup:

Normalize and convert Colors to the new Output Condition: Converts the data – for example from coated paper to uncoated newspaper paper – and optimizes the color appearance.

Optimize Total Area Coverage (TAC): Limits the maximum total amount of color without changing the color appearance.

Check overprinting CMY objects without any black

Checking overprinting CMY objects without any black is a rather rare special case. Regarding high color stability during production, fast drying times, and ink savings, we recommend using ColorLogic’s SaveInk queues for as many print jobs as possible.

However, if an overprinting object of a PDF file is composed of all CMY colors without any black, the resulting color impression from the overprinting object and the background may change after color optimization, due to the overprinting rules of the PDF standard. For an underlying object, the color of a channel is only completely visible if no color is present in the respective channel of the overprinting object. If an overprint object has just a slight amount of color in a channel, then only the color component of the upper (overprinting) object is visible.

If CMY parts of SaveInk profiles are unintentionally replaced by black and the overprinting behavior changes as a result, but the color is still to be saved, a new SaveInk profile must be created for which the exception Preserve 0% Black is activated. This special exception is located in the SaveInk module of the CoPrA profiling software.

Integration with Enfocus Switch

Enfocus Switch Integration

Working with Enfocus Switch

Even for highly advanced and efficiently configured applications like ZePrA, there are still application scenarios where special file treatment or an additional approval step for optimized PDF files make sense. This particularly applies to print providers and printing companies who receive PDF data from numerous customers that have been produced in a variety of different ways. The combination of ZePrA with Enfocus Switch and a preflighting solution has proven to be very successful for this kind of application.

Combination of Enfocus Switch, PitStop Server and ColorLogic ZePrA

ZePrA | Tools | Spot Color Report

Spot Color Report

Review accuracy of spot color conversion

Spot Color Report

Overview

The spot color report shows the results achieved with a spot color conversion in relation to deltaE00, deltaE76, and the separation into process colors. This allows the accuracy of spot color conversions to be checked before processing or printing, and to determine in advance how ZePrA converts spot colors (e.g., Pantone® or other spot colors).

Procedure

    1. Open the Spot Color Report from the Tools menu.
    2. Configurations: Select one or more configurations from the list which contain all settings for the conversion. Only Configurations which have the option Convert Spot Colors enabled are displayed in the list.
    3. Select a single PDF or image file, a spot color library or multiple files under Source Data.
      PDF or Image File: Select the PDF or pixel image file with spot colors to be processed using the settings of the selected configuration.
      Library: Select the spot color library to be converted using the settings of the selected configuration.
      File List: Add multiple files which will be checked simultaneously.
    4. Select the Sort order.
      Sorts the list according to various criteria. When sorting by Delta E, spot colors with the lowest deltaE are listed at the top, and the highest deltaE at the bottom.
    5. Create the report. It can be created in various formats (see below).
      Save: Creates the spot color report and saves it. Optionally, a Preview can be created beforehand.

    Supported file formats

    The Spot Color Report can be saved in various formats:

    • PDF
    • HTML
    • XML (both legacy and new formats)
    • Text
    • CGATS
    • CxF
    • JSON

    Note: Saving as CGATS text and Color Exchange Format (CxF) allows the file to be opened in external tools such as ColorAnt. This way, the device values (DCS) after optimization by ZePrA and the resulting Lab values can be examined. The Lab values of the spot colors in this file reflect the actual achievable Lab values resulting from the conversion via ZePrA and may differ from the original Lab values (due to out-of-gamut or other limitations).

    The two file formats JSON Files and XML Files at the bottom of the list are optimized for machine reading and are best for use by external systems to extract data for reports.
    Note: The XML (legacy format) option is only available for downwards compatibility to older ZePrA systems.

    Best Configuration: Automatically determines the Best Configuration to match the spot colors of one or several jobs from a list of selected configurations.
    Note: The configuration with the highest Score is automatically determined as Best Configuration and listed on top of the report. The highest score is always achieved by the configuration with the lowest number of channels while maintaining an equal or slightly poorer colorimetric result (compared to configurations with target profiles that use more channels).

    For example, if the spot colors of a job can be processed equally well with 7, 6 or 5 process colors on the same press, the configuration using 5 process colors is the best because it saves on inks and costs during production.

    Overview: The Preview and the spot color PDF report show an Overview and a Best Configuration section that describes how the file(s) were processed with the various user-selectable configurations.

    Score: Shows the percentage match of each tested configuration to achieve the spot colors of a job when converting spot colors to process colors (0% – no match, 100% – perfect match using a maximum of three process colors).
    Note: The calculation of the Score considers the maximum dE00, the average value (Avg dE00) over all individual dE00s of the spot color conversions and the number of channels. The configuration achieving the highest score will be listed on top under Best Configuration.

    The screenshot shows two files tested with four configurations. The Best Configuration section lists the configurations that achieve the best Score for each file.

    Process File(s): Selected files can be processed directly from the Spot Color Report window with the best configuration. The files are automatically moved to the Input folder of the corresponding configuration and automatically processed.

    The spot color report shows the results achieved with a spot color conversion in relation to deltaE00, deltaE76, and the separation into process colors.

    Note: When creating the report, all spot color settings made in the Configurations are used, including manual settings and warnings. Colors with warnings are displayed in red deltaE values.
    If the Minimize Channel function is activated, the report lists all profile variants that are created in this configuration and the spot color conversion using these variants. Hence, this can become quite a long report, which can also take considerable time to calculate and create, especially if several configurations are to be checked.

    A table of contents (TOC) in the PDF report file allows easy navigation to the details of each configuration. This is especially helpful in getting directly to the details of the individual configuration results if a spot color library has hundreds or even thousands of spot colors that have been evaluated.
    Basically, the report is structured so that the analyzed files are listed at the top in the Details section. Underneath are the configurations used per file, followed by the profile variants and their details.

    Features to streamline production

    Instead of using a single configuration with the Minimize Output Channels function, several configurations can be set up, for example for printing with the same printer but using different target profiles with CMYK, 5 colors, 6 colors or 7 colors. Then the production PDF file(s) can be checked with all possible color configurations. It may be found that the production PDF file(s) do not need 7C, but are already well suited with a certain set of 5 colors or even CMYK.

    This way, many clicks in digital printing or many plate productions in conventional printing could be saved. After checking the file(s) and determining the best matching configurations, the file(s) can be automatically processed with the configurations having the lowest maximum DeltaE directly from the Spot Color Report dialog.

    Spot Color Report Example: The screenshot shows the preview for processing spot colors with two different configurations. All spot colors found in the PDF file are included. One configuration uses a CMYK target profile and the other a 7C target profile. The report shows that in this case the 7C profile is much better suited for simulating the spot colors of the PDF file.

    Spot Color Iteration

    If spot colors have been iterated (see number 1 in the screenshot) the displayed Lab measurements and deltaE values (2) originate from the Spot Color Iteration process.

    If a final evaluation measurement has been conducted, a single asterisk is shown in the Information column (2) and the corresponding information message (3) indicates that The Lab and dE values are based on the measurements of the Spot Color Iteration.

    If no final evaluation measurement has been carried out, a message with two asterisks indicates that The Lab and dE values are based on the last applied Spot Color Iteration and may not match the actual print.