Stupid PDF question

[fredrich]

Yes, it might be a bit stupid, but I would appreciate if somebody helped me out. When I save a .pdf from Illustrator, the colour black does not seem pure black as in #000000, it's more greyish. I tried to change the colour mode to RGB, but I did not see any difference.

[obesebee]

Are you working on a file for the web or for print? If it's for print you might want to use a rich black.

[fredrich]

Are you working on a file for the web or for print? If it's for print you might want to use a rich black.

It was intended for print (as in printing it out myself on a inkjet-printer).
I chose the black from swatches.

["Technical" Terry]

If it is for print....ask your printer what "black" he would like for you to use. A rich black may not be appropriate for your piece. A spot color may be specified rather than "black". Ask.

As far as your pdf, you may have an RGB black, but when converted to CMYK is only 90% black. So when designing for print make sure you are in CMYK mode to start with.

[obesebee]

It's not really up to the printer what black you should use, that's your decision as there are a myriad of blacks to choose from. The printer can advise you though.

[jimking]

It was intended for print (as in printing it out myself on a inkjet-printer).
I chose the black from swatches.
If you are just printing it out on your desktop printer then why make a pdf?

[fredrich]

I'm not taking it to a printer, I'm printing it out myself. Aka no big deal, but I just want to know. Now, the inkjet puts little white dots in the black which is supposed to be solid. I have CMYK mode as default, but inside Illustrator the black in swatches seem to be #000000 by the looks of it, but when saved to .pdf it gets more grey-ish. I could not see any difference when converting the document colour settings to RGB and saved it as an .pdf.

[obesebee]

Try making it a rich black bay adding some CM and Y to the black.

[fredrich]

If you are just printing it out on your desktop printer then why make a pdf?

Because it is a nice format, and what I am supposed to print is made in vector (it is for a sticker sheet, so I made guides in Illu according to the measurements of the A4).

[fredrich]

Try making it a rich black bay adding some CM and Y to the black.

I think I figured it out. RGB all set to 0 resulted in: C: 75%, M: 68%, Y:67%, K:90%

Thanks.

[budafist]

When printing out yourself, try printing swatches to get the black you want.

But bear in mind that if you ever need to take that file to a printer...
Please check with your printer first.

In offset printing we can run black ink a bit heavier to make a darker black. Don't judge colour by looking at you screen. Computer screens aren't for proofing colour! Getting text that is supposed to be black but has different inks running through it can be painful to register perfectly. In fact, my printers often throw files back at me - which I in turn have to throw back at the client.

[jimking]

Budafist, ask your printer about their trapping software. It could be that the printer isn't aware of their trapping software's capabilities. With constant updates and upgrades this happens all the time with printers. In rich blacks most trapping software now, will choke c,m,y underneath 100% black allowing for easier registration on press dealing with k/o white text out of rich blacks and overhangs.

[budafist]

That's true. Perhaps they throw it back at me without putting on the press to check if their trapping software is working for them...

[jimking]

In most cases, in the printers workflow, they should be able to view the file after it's ripped. Here they can see the traps visually without having to go to press first.

[fredrich]

When printing out yourself, try printing swatches to get the black you want.

But bear in mind that if you ever need to take that file to a printer...
Please check with your printer first.

In offset printing we can run black ink a bit heavier to make a darker black. Don't judge colour by looking at you screen. Computer screens aren't for proofing colour! Getting text that is supposed to be black but has different inks running through it can be painful to register perfectly. In fact, my printers often throw files back at me - which I in turn have to throw back at the client.

Yeah, I know, but for home-use I just saw a slight difference in the black colour from Illu to .pdf (printscreened and looked at the colour code by dropping it).

[Ned]

Okay, I've got just a couple points...

#1) If sending to an offset printer, yes, you would use rich black. Rich black, however, is not those values you posted. That's probably Photoshop Rich Black (that works best on their machine), but your printer will tell you their best formula for rich black, and it will never be as saturated as the Photoshop one (at least, not that I've ever seen!). Adding more cyan (like 30% or more) is almost a given, and rest of the formula varies greatly.

#2) If printing on a desktop printer, CMYK values are largely irrelevent. A desktop inkjet printer is made to run best off the RGB gamut, as silly as it sounds. The desktop drivers don't read CMYK values, which is why you can't print greyscale without using up all 4 (or more) ink cartridges.

Your best option, if printing on your home computer, is to print from Illy, if you want the most vibrant colors. A shift is not uncommon when saved to PDF.