Strange thin line around shadows exported to PDF

Report · Nov 16, 2018

Using Adobe InDesign CC 14.0 x64 printing a document to PDF and viewing on Adobe Acrobat Pro DC 2019.008.20081.

Image portion on ID Screen:

Image portion as PDF (this thin line shows up at any resolution output):

I thought this was just a screen resolution anomaly but it does appear when the PDF's are printed. Is the problem with the background image being RGB (even though I'm converting all colors to CMYK when printing)? Is there something I can do either in InDesign or with the PDF print driver to fix this? My only other options are to create these call outs in Photoshop or remove the drop shadows altogether.

Is this a common problem? Please help!

Report · Nov 16, 2018

Stop printing to PDF and export using PDF/X-4.

What you're seeing is stitching and it's a flattening artifact.