Recompose a single PDF from PDFs that have been sent in separation

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DamienB
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Recompose a single PDF from PDFs that have been sent in separation

Post by DamienB »

Bonjour,

est-ce qu'il est faisable de séparer un PDF en autant de PDF qu'il y a d'encre ?

Et l'inverse, recomposer un PDF unique d'après des PDF qui ont été envoyé en séparation ?

J'ai des imprimeurs qui ne veulent que des fichiers séparés ou uniquement la trichromies dans le cadre de retirage au noir en plusieurs langues.

Google translate :

Hello,

Is it feasible to split PDF into as many PDFs as there is ink?

And the reverse, to recompose a single PDF from PDFs that have been sent in separation?

I have printers who only want separate files or only tri-color for black-reprinting in multiple languages.
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magnussandstrom
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Re: Recompose a single PDF from PDFs that have been sent in separation

Post by magnussandstrom »

We usually do this in our RIP or DFE with propritary "versioning" features.
Last edited by magnussandstrom on Mon May 22, 2023 9:01 am, edited 1 time in total.
freddyp
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Re: Recompose a single PDF from PDFs that have been sent in separation

Post by freddyp »

Attached are two Action Lists, one for keeping only the CMY of a file and one for keeping only the K. The principle is simply to use the "Remap color" action to remap a channel to a spot color None defined as 0% CMYK.

The splitting of a CMYK file in this way works well. What does not work well is putting them together again. You can place them on top of each other again with the "Overlay PDF" action (or with the Overlay PDF app: https://www.enfocus.com/en/appstore/product/overlay-pdf) but that is not guaranteed to give a correct result: the order of the objects changes, so overprint and transparency settings will have different effects. For example, there is a rectangle in the original below an image that knocks out everything under it. That rectangle will still be there in the CMY version and also in the K version. When you then place the K on top of the CMY it will knock out the CMY image under it. In short: it is not reliable, so do not do this.

If you need a recombined version for proofing purposes you could either use the original file or create images of the CMY and the K versions and put those on top of each other.
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Action Lists.zip
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