Black lines turn grey when saved as pdf?

[LisetteZelda]

Hello everybody,

I'm quite new to Illustrator and I just can't find the solution for my problem.

I'm designing a logo and when it's exported as PNG, the colours look perfectly fine. But when I save it as PDF, some parts of these lines turn grey. What can I do? My document color mode is in CMYK.

I've included the whole logo which I've saved as PNG, and a close up of my PDF document (with the grey lines). 

[Monika Gause]

How is the black color of each of the objects set up in the AI document?

When working with CMYK documents, in the preferences you should set up the display of black as exact.

Exactly how did you set up the export as PDF?

ALso: when opening your PDF in Acrobat, Acrobat will probably display colors exact.

100% Black is just not pitch black. It's a dark grey when printed. So probably the very dark black areas are those that cause the issues, not the lighter ones.

[LisetteZelda]

Thanks for your quick reply!

I'm not sure if I understand your first question (sorry, newbie here, still trying to figure everything out)

All lines are just black paths, black outline and black fillings. Where can I find the preferences where I can set up the display of black?

Strange thing is, I've managed to export the file as a PDF before and the grey lines weren't there that time. I've included that image below. There were a couple of changes needed, and not necessarily on all the areas that include grey lines now. I don't know what I'm doing wrong/differently this time. My set up for export to PDF was Image > Save Copy > Select PDF and then just the standard presets (tried to play with that too to see if that made any difference).

[Monika Gause]

"Black" - what do you mean?

Black as in pure 100 K? Or is it some 100/100/100/100?

Please tell us the exact definition.

If this is going to be printed, then most probably you want 100 K in a logo. Which won't look pitch black.

As a newbie you probably want to learn about how printing works in order to avoid some very costly mistakes. And since that would be very elaborate (as in a couple of years experience), it cannot be explained in a forum post.

[LisetteZelda]

Black as in 100/100/100/100.

I know it can be expensive and I strongly want to avoid that, that's why I'm asking this question. This is going to be printed. I'm still a student, and I'm not delivering products to costumers when I'm not 100% convinced it's allright. And I can't figure out where those lines came from, since they weren't there the last time I exported it to PDF.

Thanks for the link, I will defenitely look into this.

[Monika Gause]

Don't use that kind of black in your designs. In 99% of cases it will lead to an absolute disaster in print.

Since you are still a student, demand of your university that they teach you this. It would be irresponsible to not teach you the basics of printing.