Editing and Measuring Spot Colors

  • Individual new spot colors may be entered as solid tones or gradations via the New button under Define Spot Colors and the Edit Spot Color dialog will open.
  • To enter a new spot color: Enter the name of the spot color in the Edit Spot Color dialog. The Name should be written as it is referred to in the PDF documents since it is used as an identifier and will allow the automatic conversion to be performed successfully.

    Tip: If separate libraries are created for different substrates or printing process, the same spot color name will occur in different libraries but with different measurements. To avoid this causing issues, select the required library for the color conversion in the configuration.
spot-color-edit

Editing a Spot Color

  • Use the Non Printing Color checkbox to define whether the indicated name of the spot color corresponds to a non-printing color (die-cutting marks, braille, coatings, etc.) and should be converted. Checking Non Printing Color will make the necessary settings automatically. Close by clicking on OK.
  • If the spot color is available printing on white and black backgrounds, enter both prints by manually measuring or importing measured values and use it for further processing. Choose between Printed on White Background (Substrate) and Printed on Black Background (Process Black) to specify if colors created or measure are saved on white or black backgrounds.
  • To process a ‘real’ spot color, indicate only the 100% solid tone or gradations of the spot color by selecting the Solid Tone option for the 100% value (opaque) of the spot color under Use Template. For complete wedges, select one of the two templates with three gradations (3 patches: 0%, 50% and 100%) or eleven gradations (11 patches in 10% increments). Alternatively, use the Import button to load a spot color that has already been measured and is available in the form of a measurement file.
  • When a printed wedge with gradations of the spot color does not correspond to either of the predefined templates, use the Add button and the Additional Tone Values dialog to create the gradations of the wedge in the form of percentage values. Enter a blank space between the percentage values and confirm with OK.
  • The personal wedge is marked as Custom and you may click on Save as Template for later use.
  • There are three options for entering measurements which include manually entering the LAB values for each gradation, select Measure to use the Measure Tool supplied with ZePrA, or by using Import to use existing measurement files. 

    Tip: It is recommended to print a wedge of the spot color directly onto the respective substrate as well as a second wedge of the spot color was an overprint with the black process color using the correct printing conditions and then measure them spectrally in ZePrA. This will allow ZePrA to perform high quality conversions for the solid tones and the gradations and the opacity, taking the dot gain into account in the process. Compared to LAB measurements, spectral measurement data is more capable of simulating overprinting spot colors.
  • Clicking on Measure opens the Measure Tool. For further information on Measure Tool please read Measuring Spot Colors with Measure Tool
  • Once measuring is complete, a dialog appears in Measure Tool indicating the measurement is complete and can be transmitted into ZePrA by clicking the Transmit button. This will close Measure Tool and the Edit Spot Color dialog will reappear. To add the measured spot color to the color library, select OK.
  • Opacity indicates how translucent or opaque a color is.

    Tip: From the measured values with black background, ZePrA will automatically calculate the opacity and take the value into account during the color conversion of spot colors. Information from the ink manufacturer regarding the opacity of the spot color can be entered directly as a percentage and no measurements on a black background needs to be performed. Calculate and display the opacity from the measured values on black using the Calculate button. The value calculated can also be changed manually. Without any information regarding opacity, ZePrA will assume the spot color is fully transparent at 0%.

 

Tip: The Define Spot Colors table indicates whether a spot color in the library consists of just a solid tone or of several gradations, as well as whether the color values are of the spectral type or LAB type. The opacity of the spot colors is also shown when available. Color values can be edited, deleted and added to or moved to another library at any time. When moving a color to another library, select one or more colors and right click to choose which library the color(s) should be moved to.

Measuring Spot Colors Measure Tool

On certain measuring instruments the measuring mode can be changed to M1, M0 or M2. Select the mode that fits the measuring requirements. Select the measuring mode for the wedge layout and select the Measure button on the instrument.

Note: Barbieri measuring instruments are optimized for test chart measurement therefore single patch measurement is not available.

Once measurement is complete, the measured color appears in Measure Tool. A dialog indicates that the measurement is complete and can be transmitted back to the main program by clicking the Transmit button which will close Measure Tool and make the measured values available in ZePrA. Saving the measured values in the Measure Tool is not required.

Measure Tool comes standard with installation of ZePrA. If the software is no installed on the computer, the measure button in ZePrA is not available. With the Measure Tool the following measuring instruments are available:

 

Barbieri Spectro LFP

Barbieri SpectroPad

Konica Minolta FD 7/5

Konica Minolta FD-9

X-Rite eXact

X-Rite i1iO

X-Rite i1Pro 1 (without XRGA)

X-Rite i1Pro 2 (XRGA)

To use a measuring instrument, connect the instrument to the computer via the USB port and click the Measure button in the Edit Spot Colors window in ZePrA. Measure Tool will start and the rest of the process is completed within the software.

In most cases, select the Others button under Test Charts on the Measure tab and select the reference file for the test chart that has been printed and needs to be measured from the dropdown menu. These options will be unavailable in the event of solid tone or wedge measurement from within ZePrA. If the solid tone is selected, a single color patch is preselected for the measurement. If the wedge is selected, the layout of the wedge selected in ZePrA is displayed. Under Measurement Instrument, select the measuring instrument connected to the USB port from the dropdown. Click Connect and follow the instructions.

In single patch measurement, only one color is measured and transmitted at a time in Measure Tool. Use the Repeat button to restart the measurement in the event of an incorrect measurement.

The Measure Tool Window