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How do I get the right colors for my proofs?

There are two main things you must do to ensure that the correct colors are used in your proofs. They are described in more detail below. Briefly...

 

To set up the printer properly...

...and maximize the color accuracy of the proof, make sure you follow these steps:

  • Align printheads to maximize the print quality of the proof.

    For details on how to align printheads, see The problem is bad or poor print quality.

  • Calibrate your printer for color with the media you are going to use for the proof.

    Make sure that the printer is calibrated. You can check that the calibration you performed is successful by checking the Color calibration curve tab of the HP Designjet software. It should show a calibration file with the current date. See Color calibration for information about checking and performing color calibrations.

  • Get the right ICC input profile for the target you are going to emulate.

    The printer already incorporates several ICC profiles for generic offset standards like SWOP, Euroscale, TOYO, and DIC, using standard offset stock. To maximize the color accuracy you should get the specific ICC profile for the press and media you are going to use (or you already used) in the offset process. The more calibrated the offset is and the more standard the paper is, the better the results will be with just the generic ICC profile, and therefore a specific ICC profile will be less likely to be needed. In any case a specific ICC profile will provide better results than the generic ICC profiles included with the printer.

    See How do I create and add an input profile?

  • Get the right file.

    Make sure you have the same file you will use (or you already used) in the offset press.

  • Make sure you have the right media loaded in the input tray.

    The media that is going to be used needs to match that specified in the HP Designjet software to get accurate colors and should be closest to the media that is going to be used (or already used) in the offset press. Chose the right media that is most appropriate for the job you want to simulate. For example, if you want to proof SWOP coated stock, you may chose HP Proofing Semi-gloss. For proofing matte stock, chose HP Proofing Matte.

  • Use HP-approved inks and Proofing media.

    The name of the media being used should be selected in the Media field. The output ICC profile will be selected automatically by the HP Designjet software based on this media selection and the printmode selection. This is why it is important to select the media and print mode correctly. The printer supports three proofing media. To add additional media, new ICC profiles will have to be added for each combination of media/print mode.

    If HP media is not used, select the closest representation. For example, if using glossy media, select HP Proofing Gloss.

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To use the correct settings in the HP Designjet software...

  • Select the job in the HP Designjet software; go to Setup > Job Properties > Print.

    Select the appropriate media and print mode.

    Perform color correction should be checked. This enables ICC color management in the HP Designjet software.

  • Set the ICC input profile.

    The appropriate 'emulation' profile or press profile must be selected in the "ICC input profile. CMYK" field. Select the input profile depending on the offset press standard appropriate. If in doubt, we recommend "SWOP".

    An input profile contains the color characteristics of the device you are trying to proof. You can select the input profile according to whichever device you want to emulate. If it is a press, select DIC, Toyo, Euroscale or SWOP. Do not select "Generic". This is a simple transformation.

    If you are trying to match a specific press with a specific media (since SWOP is a generic standard), an appropriate emulation ICC profile must be generated for that press and added to the list of available profiles. This requires a color measurement device and a software package which generates ICC profiles. Emulating a specific press will usually yield a closer color match than with a generic SWOP profile, but requires access to the tools mentioned above.

    Note that input profiles can be created and added in order to emulate the device on which the final job will be printed (for example, a digital press).

  • How do I create and add an input profile?

    The input profile for the press will normally be created by the Pre-Press House or Commercial Printer on their device using the tools mentioned above. They will need to provide you with a file containing this profile. Once you have the file, copy it to your hard drive, to the following folder:

    • For Macintosh:
      Hard drive:hp Designjet 10ps RIP:icc profile:CMYK
    • For Windows:
      C:\Program Files\HP Eiffel\ICCProfile\Cmyk

    Then the profile will appear in the list of input profiles in the HP Designjet software user interface.

    Note, there are two options for the input profile section--CMYK and RGB. If you are comparing a print to another print, it only makes sense to use CMYK. Use RGB when you are comparing to a monitor.

  • Set the rendering intent.

    In the ICC output profile section, select the appropriate rendering intent (see the section on rendering intent in the Color management tutorial). In order to achieve color accuracy, you should use either relative colorimetric or absolute colorimetric.

    The output profile appears automatically because of the selection of media and print mode.

  • If necessary, set Automatic Pantone calibration.

    Notice that automatic Pantone Calibration can be on or off. If in your file, you have CMYK colors and you also have Pantone colors, the automatic Pantone calibration only applies to the Pantone colors. Automatic Pantone calibration if checked will assign the right CMYK combination for that Pantone. If you have Pantone colors in your input profiles, then check the box.

See also:

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