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tully1254
Known Participant
January 8, 2019
Answered

Transparency Blend Space RGB / CMYK

  • January 8, 2019
  • 3 replies
  • 18864 views

There is option in Transparency Blend Space to set Document as RGB or CMYK.

When I close file for print I use one of the Indesign colour profile options (fogra 39).

Will it affect the outcome of the printing if document is set in RGB rather than CMYK?

    This topic has been closed for replies.
    Correct answer rob day

    There is option in Transparency Blend Space to set Document as RGB or CMYK.

    The blend space only affects the preview of a spread that includes any transparent object. It doesn't actually change an object's color, and if there are no transparent objects on the page, it has no affect at all.

    A blend space is needed because InDesign allows a mix of RGB, CMYK, or Lab colors on the same page, all of which can be blended together via transparency effects. For postscript print output, the page has to be flattened into a single color space, which is defined by the blend space. The Transparency Flattener preset you choose in the Print dialog's Advanced tab affects how the flattening is handled.

    If you export to PDF, the transparency can be kept live and still contain a mix of color modes—the PDF/X-4 preset.

    3 replies

    Legend
    January 9, 2019

    Never use Postscript to make a PDF with InDesign. Just never.

    Not sure what level of experience you’re coming from with this. Are you familiar with the CMYK gamut? Are you working with a CMYK profile supplied by your print provider?

    tully1254
    tully1254Author
    Known Participant
    January 9, 2019

    I do have a considerable amount of experience in Indesign, but I am not familiar with the CMYK gamut.

    Yes, I am working with CMYK profile the printer has provided - FOGRA39.

    rob day
    Community Expert
    Community Expert
    January 9, 2019

    Yes, I am working with CMYK profile the printer has provided - FOGRA39.

    If the destination is an offset press, you would want to turn on Overprint Preview in order to get a print preview. That will preview all RGB or Lab color, whether there is transparency or not, in your document's assigned CMYK profile's color gamut. Make sure FOGRA39 is the document profile assignment. An existing document's profile assignment isn't necessarily set in Color Settings, check Edit>Assign Profiles...

    rob day
    Community Expert
    rob dayCommunity ExpertCorrect answer
    Community Expert
    January 8, 2019

    There is option in Transparency Blend Space to set Document as RGB or CMYK.

    The blend space only affects the preview of a spread that includes any transparent object. It doesn't actually change an object's color, and if there are no transparent objects on the page, it has no affect at all.

    A blend space is needed because InDesign allows a mix of RGB, CMYK, or Lab colors on the same page, all of which can be blended together via transparency effects. For postscript print output, the page has to be flattened into a single color space, which is defined by the blend space. The Transparency Flattener preset you choose in the Print dialog's Advanced tab affects how the flattening is handled.

    If you export to PDF, the transparency can be kept live and still contain a mix of color modes—the PDF/X-4 preset.

    tully1254
    tully1254Author
    Known Participant
    January 9, 2019

    I am working with a lot of light-up images with colours that look vibrant on screen, and I want to know which PDF setting will maintain as much vibrancy as possible in the printing.

    Will the postscript PDF set in RGB colour give better results than exporting?

    Or exporting using the PDF/x-4 preset?

    Legend
    January 8, 2019

    Yes. All objects on the page are converted to the transparency blend space at some point, and perhaps back again to an output space.