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adamw
06-23-2013, 01:33 AM
Hi everyone. I have a question regarding RGB and CMYK files. What is the correct way to handle a situation where a client provides RGB TIFs, rather than CMYK, and they intend to print the book?

Is it appropriate for me to convert the page to CMYK in photoshop, or should I just letter the page as is (or something else)?

Thanks!

JimCampbell
06-23-2013, 05:07 AM
Is it appropriate for me to convert the page to CMYK in photoshop, or should I just letter the page as is (or something else)?

Ask the client. It's the only way. If they don't know the answer, ask for a contact at the printers, and ask them how they want the files instead.

Some printers nowadays ask for RGB files and handle the CMYK conversion at their end — if your client is using one of those, then you'll be creating work for yourself and submitting off-spec files if you convert to CMYK at your end!

Cheers

Jim

adamw
06-23-2013, 11:07 AM
Thanks, Jim!

Unfortunately, I don't think he has picked a printer yet. I'll go ahead and see what he prefers.

vartemis
06-23-2013, 05:20 PM
Ask the client. It's the only way. If they don't know the answer, ask for a contact at the printers, and ask them how they want the files instead.

Some printers nowadays ask for RGB files and handle the CMYK conversion at their end if your client is using one of those, then you'll be creating work for yourself and submitting off-spec files if you convert to CMYK at your end!

Cheers

Jim

What printers have you worked with that ask for RGB out of curiousity, Jim? The only one I know of is KaBlam, and that's because they are essentially printing on large laser printers.

My templates are all CMYK, so when I place the art in, it converts it. The problem with the RGB files is they aren't going to be trapped properly. If you are using a POD printer, it won't matter because there is no slippage in a laser printer. If you are going to be printing it offset, your colorist has created a problem that they will have to correct, or you run the risk of having an ugly looking book.

I know a lot of colorists work in RGB with the CMYK range on. Photoshop is an RGB program, so a lot of their filters and whatnot do not work in CMYK. But when the colorist is finished, they should be converting the file over to CMYK and trapping the black channel. It's always easier to go CMYK->RGB than RGB->CMYK.

j

adamw
06-23-2013, 06:53 PM
Hi Vartemis,

That's what I thought too (easier to convert from CMYK to RGB, than the reverse), but, this is what I've been given.

Another question has popped up from this. So, I have these RGB pages, but I want my lettering to still be CMYK 100K.

Here's what's going on: I load a page with an RGB color profile into Illustrator. I copy and past all the text from the script into illustrator (always on it's own layer). I make sure they are all set to 100k with no others CMYK values. Then, seemingly like magic, the CMYK values all change to the following:
- C= 69.76
- M= 67.52
- Y= 63.86
- K= 73.96

I'm not manipulating them other than clicking back and forth between the balloons and the text. The same thing happens with the black stroke of my word balloons. I'll set them to 100k, then they automatically switch to the values I've listed above. Am I missing something there? We don't want to sent a file to a printer with a mixture like that, right?

Some more info. The "document color mode" is set to RGB, but that's because I opened an RGB file, correct?

Any solutions or advice as to how I should proceed?

Thanks!

JimCampbell
06-24-2013, 03:43 AM
What printers have you worked with that ask for RGB out of curiousity, Jim? The only one I know of is KaBlam, and that's because they are essentially printing on large laser printers.

No one that I'm dealing with directly, but it comes up periodically in queries on some of the design forums I visit. I certainly don't have the impression that it's common, I just mentioned it as a possibility.

Cheers

Jim

JimCampbell
06-24-2013, 03:48 AM
Some more info. The "document color mode" is set to RGB, but that's because I opened an RGB file, correct?

It's the document color mode that's causing you the problem because it's RGB, then the only black it can 'understand' is R0G0B0 and the CMYK values are simply an approximation of that.

You can place an RGB image on a CMYK Illustrator document without having to convert it first. You'll have more control over the CMYK conversion if you do it in Photoshop first, but at a push you can place the RGB image in Illustrator and export a CMYK file from AI at the end.

Cheers

Jim

adamw
06-24-2013, 01:13 PM
Great! Thanks, Jim!

adamw
06-24-2013, 01:47 PM
Update: It turns out that he is going to print them initially with a print on demand service that is requesting RGB files, so he had the colorist format them for RGB from the beginning.

Because everything will be RGB and a digital printer isn't using plates, would it make a difference if I letter this batch it straight RGB for now and then redo it in CMYK if/when he needs the files for a standard printer?

Will the weird values (C= 69.76, M= 67.52, Y= 63.86, K= 73.96) look bad if printed? Am I better off dropping the RGB file into a CMYK document and then outputting it as RGB, or is that going to screw it up even more?

JimCampbell
06-24-2013, 03:45 PM
Update: It turns out that he is going to print them initially with a print on demand service that is requesting RGB files, so he had the colorist format them for RGB from the beginning.

The annoying thing about this is that printing WILL be done in CMYK — it can't be done any other way. It's just that POD services are so used to dealing with people who don't have a clue that it's easier to ask for something punter will understand (RGB JPEGs, usually) and either do the conversion themselves or just let the RIP handle it…

Short version: there is no way to get K100 text in this workflow. You need to flag this up with your client as an issue inherent with this sort of POD service. It probably won't look catastrophically bad — in fact, there's a chance that no one but a letterer will even notice, but you should flag it up anyway to cover your behind.

If it was me, I'd put the RGB images on a standard CMYK mode AI page, treat all the lettering as if it was going to be printed in CMYK and then just export RGB files at the end. That way, when/if you go to proper press printing, you can just run a batch RGB -> CMYK conversion on your existing art files in Photoshop, update the linked files on the AI docs and then export CMYK files.

Cheers!

Jim

adamw
06-24-2013, 04:19 PM
If it was me, I'd put the RGB images on a standard CMYK mode AI page, treat all the lettering as if it was going to be printed in CMYK and then just export RGB files at the end. That way, when/if you go to proper press printing, you can just run a batch RGB -> CMYK conversion on your existing art files in Photoshop, update the linked files on the AI docs and then export CMYK files. Jim

Thanks, Jim! That's what I'll do. The client has been very receptive to my comments regarding this issue, so he's aware of it and we're just trying to make sure we both get it correct (and that I'm not inadvertently screwing something up in the process).

Thanks again! You've been a tremendous help!
- Adam