Exporting from a Working CMYK to sGray keeping the spot colour of the folding
Hi guys,
I was wondering if you can give a hand with this, I've been playing around with different settings but I did't manage to fix it by myself.
So, I'm working in CMYK in Indesign CC 15.0.3. It's an instruction for use, so it will printed in litho/offset purely in gray scale but I added some folding lines as spot color pantone magenta in a different layer.
The problem I have is that as soon as I export the document (which is color proofed as Working CMYK) to sGray (PDF/X-1a:2001, Acrobat 4 PDF 1.3, Optimize dor Fast Web View, Export Layers: Visible & Printable Layers, Default Compression, All printer's marks addes less the bleed mark, including the document bleed settings, Color Conversion: Convert to Destination, Destination: sGray, Profile Inclusion Policy: Don't Include Profiles, Default Ink Manager and rest of it is default) it saves the content properly with the grayscale but converting the folding lines as well to grayscale. I would like to keep those ones as spot color. But the only way I found it was by exporting it with Color Conversion: Convert to Destionation (Preserve Numbers) and then Coated FOGRA39 (ISO 12647-2:2004), Profile Inclusion Policy: Don't Include Profiles and default Ink Manager.

Normally I just work as usual with Fogra39 CMYK saving it as PDF/X-1a:2001, Acrobat 4 PDF 1.3 and then the printers do the separations. But this time the printer asked me to send them a grayscale file so it will match better with the color proofed file the send me for the final OK before they send it to the machine.
ANY IDEA ABOUT IT?
