Spot colour PDF question

[Teej]

Howdy,

OK here's the scenario: I've designed several pieces of artwork for the same project all in the same 2 spot Pantone colours. Fine. I have now been asked to provide one of the pieces as a poster which will be run off on a digital printer (Indigo I'm guessing).

Is it safe to print to a pdf using the "convert all colours to CMYK" option on an adapted joboptions file or should I go through the document converting all instances of the 2 spot colours to the equivalent CMYK versions (I realise the colours won't be anywhere near as rich)? Obviously the former option is a heck of a lot easier, but I'm not sure how good Distillers conversion would be.

OK another question that's popped into my head which I might as well ask while I've got you here is that whenever I do a 2 colour job which includes a DCS image the printer asks for the Quark files rather than a PDF. Are there issues with printing a PDF from a job that includes DCS images?

Thanks Prepress gurus, where would us designers be without you? :D

[Broacher]

From Adobe's InDesign help files:

"DCS files are intended to be used in a pre-separated, host-based workflow. In most cases, color separations files associated with a DCS image are excluded when you export or print a composite to a PDF, EPS, or PostScript file. (The sole exception is made for 8-bit DCS files that were created in Photoshop and that do not contain vector graphics.)"

So the exception for DCS in PDF -- at least for ID users, is 8 bit without vector stuff. I'm not sure about Quark's handling of this though. Might have to e-mail F. Flintstone on that one.

If you're working in ID, the whole DCS/PDF question is kind of moot as you can just add spot colour channels to a 'blank' greyscale (or a CMYK) PSD or TIFF and get those channels directly into the final PDF still separated (but also visible)-- as well as maintain the option to add transparency to the whole placed image. If that's not important, you could save your Photoshop DCS work to Pshop PDF and also get vector shape and type 'as vector' support. Purty neat.

[doubting_thomas]

Howdy,

Is it safe to print to a pdf using the "convert all colours to CMYK" option on an adapted joboptions file or should I go through the document converting all instances of the 2 spot colours to the equivalent CMYK versions (I realise the colours won't be anywhere near as rich)? Obviously the former option is a heck of a lot easier, but I'm not sure how good Distillers conversion would be.


Why do they need you to do the conversion, or have you asked if you need to?
I'm not really sure why they'd request it, but if it's color critical it could be a
PITA. Spots to process rarely are close enough to slide by. Distillers conversion
is as good as the color profile you are using IMO, but I don't do a lot of 4cp
work here. You may want to do some testing...


I hope this helps in some way...

[Teej]

I'm not sure about Quark's handling of this though. Might have to e-mail F. Flintstone on that one.

http://www.ttr-dcli.org/phpBB2/images/smiles/lachen.gif

Thanks guys,

Why do they need you to do the conversion, or have you asked if you need to?

Are you suggesting that I give the printers a spot colour pdf and THEY do the conversion themselves when they RIP it? Haven't actually asked by the way, d'oh!

As for the other question... all the DCS files I create are 8-bit DCS files that were created in Photoshop and that do not contain vector graphics so that should be hunky dory. It's no big deal emailing the collected folder anyway, I was just a bit curious.

[doubting_thomas]

Are you suggesting that I give the printers a spot colour pdf and THEY do the conversion themselves when they RIP it? Haven't actually asked by the way, d'oh!


Yes, I'm suggesting that you give it to them unconverted, but you'll want to
give them a printed sample of what color you're aiming for, too. After reading
a little about the Indigo it looks like it's designed to hit a wide range of spot
colors. I haven't run one, so I'm not sure how true that is. I've run a Xerox
Docucolor 2060, and it's pretty good (not perfect) at hitting PMS colors,
or at least getting in the ballpark with some operator calibration and curve
adjustments. If you give them a color sample and proof to it, you shouldn't
have too many problems, IMO. It probably won't be perfect though.

[Teej]

Thanks a lot for the info DT, to be perfectly honest the clients aren't expecting that they will match the spot colour versions perfectly anyway (we have told them so). So it ain't a big deal.

[CamarotaDesign]

See if your printer can provide a Pantone to CMYK swatch conversion book for their digital press. Our printer uses the nexpress, and he gave us a swatch book that shows how the conversions will come out. Gotta be a little careful, some pantone colors convert horribly, and then one that is nearly the same converts almost perfectly.

So for this recent brochure job I did, I found pantone colors that converted well, sent the PDF with the specified pantone colors and they came out absolutely beautiful. I was so happy I cried. lol.

[Broacher]

A lot of higher-end output RIPs and devices include built-in Pantone lookup tables, containing the best-match mixes tuned to that specific device. Talk to your output service and see if that's the case.