In this article, you will learn
- which prerequisites are required for this Fixup, and
- how to apply this Fixup.
1. Introduction
The Fixup Set Black Objects to Knockout is available in the Workflow. The purpose of this Fixup is to set black vectors, text or vectors and text to Knockout.
2. General
Use the Fixup Set Black Objects to Knockout to set black objects to Knockout. A typical application would be, for example, if you want to print a purely black text in digital printing with water-based inks. Print with 100% black to ensure that the maximum ink application is not exceeded,
You can find this Fixup on the tab Data Preparation of an Article, Order or Production Job by:
- entering the name of the Fixup in the area Filter,
- activating the option Object in the area Category,
- activating the option Change in the area Action,
- activating the option Overprint or Knockout in the area Property.
3. Description
This Fixup sets the overprint status of all pure black – 100 % grayscale and 0/0/0/100 in CMYK - objects (vectors and/or text) to Knockout. Please note that the objects must be black with the aforementioned values.
3.1. Prerequisites and Functionality
For the Fixup to perform as intended, the following requirements must be met:
- The file contains purely black objects.
- The black objects are created in CMYK (0/0/0/100) or grayscale (100 %).
Figure 1: The dialog of the Fixup Set Black Objects to Knockout
The following options can be used to set black objects to Knockout:
- Templates [1] – settings selected in the dialog can be saved as a template and applied to other Articles/Print Items, as well as used within Fixup Chains and in the Operations Apply Fixups and Check Print Item and Apply Fixups.
- Apply to [2] – select which objects should be set to Knockout in the selection menu. The following options are available:
- Vector – only black vectors are set to Knockout.
- Text and Vector – all black vectors and texts are set to Knockout.
- Text – only black text is set to Knockout.
- Variable Content [3] – for Variable Content [3] , select the desired placeholder – Database Field or User-defined Field – from which the value for the selection of objects should be retrieved. The following values must be found in the selected field for the respective objects to be selected:
BlackLineArtBlackObjectsBlackText
Figure 2: Values in the selected field for the option Apply to
3.2. Before/After
To experiment with this function, refer to the sample file "Sample_Set Black Objects to Knockout.pdf". The file contains black text and black vectors. Both objects overprint and should be set to Knockout.
After applying the Fixup, the file "Sample_Set Black Objects to Knockout.pdf" is created. The overprint status was set from overprinting to Knockout. The values from Figure 1 were used for this.
Figure 3: Left: Original file; Right: Edited file in which all black objects were set to Knockout
Article update: Workflow 1.20.1 – 04/2025