Non-transparent areas printing darker than they should be

[benfrew]

Hi,

I'm having some problems with a print on a Vario/Roll-Up/Pull-up, whatever you call them in your region.

Basically, every area which does not have a transparent object in it has printed dark. I've never had this before over 1000+ print jobs, the big majority of which feature some transparent objects.

This is the final print:

And this is the transparency preview:

So it's clear that those areas not in red, but in layers or arrangement below those which the transparent objects appear are the ones that have printed darker.  To be clear, the objects which are within the boundries of the red areas above have all printed in correct colour.

All content is in CMYK, I believe it was exported to PDF/X-1a:2001 - could the export be causing the problem?

Can anybody help?  What am i missing?

Thank you in advance.

InDesign CC 2017.0

Windows 7 64bit

Dell Precision M6800

[rob day]

All content is in CMYK, I believe it was exported to PDF/X-1a:2001 - could the export be causing the problem?

So this is being printed on some kind of composite inkjet printer, not offset?

PDF/X-1a would flatten and convert all color to CMYK and composite inkjet printers are usually happier with profiled RGB.

Have you opened the PDF the print was made from and checked that the dark areas are not in the PDF?

[Danny Whitehead.]

Are you printing this, or sending it to a printer?

As Rob has suggested, the first thing to check is the actual CMYK values in the PDF, by hovering over the relevant areas with Acrobat's Output Preview. You can also check in ID before making the PDF, with Separations Preview.

Also, be sure there aren't any spot colour swatched used in the ID file.