checking soft proof pdf for oversaturation

Thanks for your very informative responses, everyone. I should have been a little clearer in my original post: I have not yet chosen a printing company, so the destination CMYK profile is not actually US SWOP - I was just using that as an example.

I know that the output will look slightly different depending on which profile the printing company uses. And I realize that ultimately the printing company can prevent oversaturation by limiting the amount of ink to a given value (such as 300%).

However, there are a lot of photos in the book (including a lot of black in the B&W images, and a lot of dark colors in the color images). I know that things can look very different (usually much darker) printed on paper, as compared to how they appear on a computer screen in RGB. I want to make sure that the finished product is as close to what I want as possible. So I'd rather weed out any potential problems (such as loss of detail in the more shadowy parts of photos) by adjusting files before we get to the prepress stage - especially since I may not be able to be there for printing.

Hi @Jonathan28895428q83g , Could you clarify whether you are referring to total ink limits or out-of-gamut color?

InDesign’s Overprint/Separation Preview is the equivalent of Photoshop’s default Proof Colors, which with an RGB image uses the current Color Settings’ Working CMYK profile for the soft proof. InDesign documents have RGB and CMYK profile assignments, so its Separation/Overprint Preview uses the document’s assigned CMYK profile for the soft proof.

An AdobeRGB Photoshop image with out-of-gamut color previewed as RGB

Same file with Proof Colors turned on—the default Proof Color Setup is Working CMYK, US Web Coated SWOP in this case:

In InDesign with Overprint/Separation Preview turned off, the image soft proofs as AdobeRGB—its embedded profile:

With Overprint/Separation Preview turned on, the soft proof and output numbers are to Document CMYK, US Web Coated (SWOP) in this example:

In Acrobat, go to Tools> Print Production> Output Preview.

Let your printer worry about ink coverage, as this may be specific to printing conditions.

I'm thinking that by oversaturation you mean more ink than the paper can absorb (the ink limit). You can check for too much ink in the shadow areas (the only place it will occur) in the Separations Preview panel by choosing Ink Limit and set it for the appropriate value. I believe SWOP has a 300% limit in the defintion, but you should check with the printer to see what they recommend. You should assign the correct CMYK profile in the document using Edit > Assign Profiles... before checking.

Ask the printer if they have a PDF .joboptions file you can download, or if not what settings they want you to use.

Yes, that is the purpose of Window > Output > Separations Preview

I am alarmed that a book printing company wants you to use U.S. Web Coated SWOP v2. Are you sure? Are they operating on old knowledge?

I would start with an export joboption like PDF-X/4 and maybe modify it with your correct destination colorspace. Nowadays that is more likely to be something like a FOGRA or especially a GRACOL. I would double-check that with someone knowledgable at your commercial printery.

Adobe Acrobat Pro also has a similar tool inside it for preflight/prepress stuff. Look for Acrobat > Tools > Print Production > Output Preview. Make sure you require a color proof and that you are there for the press run if at all possible.