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This article compares creation of a derived print calibration curve in Harmony to the equivalent operation in ColorFlow.

It applies only to derived print calibration curves where:

  • the current curve represents the measured tonality of the print condition, without calibration curves (except perhaps a plate linearization curve)
  • the target curve represents measured or published tonality of a print condition that you wish to match, such as ISO TVI curves, SWOP target tonality, etc.

Another common usage for derived calibration curves where:

  • the current curve is linear
  • the target curve input and output values are the nodes of a desired calibration curve, produced by human expertise or third-party software.

This latter use case is not addressed by this article. Instead, see Creating a print transfer curve by Tint In/Out Points.

The following table provides a side-by-side comparison of creating a derived print calibration curve from measurement data in Harmony and ColorFlow. The left column lists the tasks you would perform in Harmony; the right column lists the equivalent tasks in ColorFlow.

HarmonyColorFlow

Create a print current curve

  • In the Print Curves tab, under Calibration Curves, click the Add button .
  • In the Devices window, create a named press and drag it to the viewer window. Close Devices.
  • Click the Properties icon  and define the device condition.
  • Click the Measurement icon .
  • You can either measure a chart or import an existing Harmony current curve with real measurement data.

    1. In the Chart tab, click the Add button .
    2. In the Chart Type dropdown list, select Tint Ramp.
    3. Click Save.
    4. Print the tint ramp chart with the device condition that you want to calibrate.
    5. Click Measure.
    6. In the Characterization Print Curve dialog box, choose the print curve used to output the tint ramp chart in Prinergy.
    7. Click OK.
    8. Follow the measurement wizard to measure or enter your measurements.
    1. Click the Measurements tab.
    2. Click Import.
    3. Locate and select the Harmony file, Open.
    4. In the Import Harmony Print Measurements windows, select the current curve of the press, OK.
    5. To check the press response, click View and select Tone Value Increase View . If the CMYK midtone gain values are not between 15% and 45%, the current curve is likely not real measurement data. Measure a printed chart for meaningful press measurement data.
    6. Click Close to close the Device Measurements window.
Create print target curve
  1. Click the Calibration icon .
  2. If you want the curve to be visible for selection in Prinergy, select the Show curves in Prinergy check box.
  3. Click the Process Inks tab and select the desired target device condition from the Target dropdown list.
    ColorFlow provides a list of built-in industry CMYK specifications that you can use as your target response. If you can't find the desired target from the list, you can create a custom CMYK Reference device condition as your target.

  4. In the Curves Method list, select Tonal Match.
  5. Click OK.

    1. Click the Device Conditions tab and then click the Add icon .
      The Device window appears.
    2.  Drag the CMYK Reference to the viewer window.
    3. In the device condition, click the Properties icon .

    4. In the Name list, type a name.
    5. Leave the default value for Separate Same As and click  select a device type that best represents the black generation strategy of the reference device condition. For the US Web Coated SWOP reference, select Offset  Press - Heatset Web.
    6. Click OK.
    7. Click the Measurement icon .
    8. In the Device Measurement dialog box, click the Add button .
    9. From the Chart Type list, select Tint Ramp.
    10. Click Save.
    11. Click Measure.
    12. Click Enter manually.
    13. Click a color channel (C, M, Y, or K), or in the Channel Binding section, select C, M, Y Same or C, M, Y, K Same.
    14. In the Tonal Response section, double-click the EDA area of a desired tint in, and then enter your EDA value.
    15. Click OK and close the Device Measurement dialog box.
    16. In the Device Conditions list table, find the device condition that you just created and select the Show in Target List check box.

       To import a Harmony target curve:

      1. Click the Measurements tab.
      2. Click Import.
      3. Locate and select the Harmony file, Open.
      4. In the Import Harmony Print Measurements windows, select the target curve, OK.
      5. To check the press response, click View and select Tone Value Increase View . If the CMYK midtone gain values are not between 15% and 45%, the target curve is likely not real measurement data. Use another method described above.
      6. Click Close to close the Device Measurements window.


      Click the Process Inks tab and select the desired target device condition from the Target dropdown list.
      ColorFlow provides a list of built-in industry CMYK specifications that you can use as your target response. If you can't find the desired target from the list, you can create a custom CMYK Reference device condition as your target.

Create a derived calibration curve based on the print current and target curve

The print calibration curve is generated for you

Edit the print calibration curve:

  1. Edit the print current curve.
  2. Edit the print target curve.
  3. Re-create the print calibration curve based on the modified current and target curves.
  1. See Adjusting a print calibration curve.
  2. You can click Calibration Curves to display the curve graph and see the result of your adjustments. 
  3. To preview the effect of your adjustments, click Preview and select an image file.
  4. Click Apply.



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