Is there a way to convert anything that is 100%CMYK to a spot color?

[cbishop01]

The issue i'm having is that the artwork is made in photoshop and is 400% coverage. 100%CMYK, is there a way when exporthing the artwork to have it merge with a  spot color?

[rob day]

I can't see any one process that would solve this for multiple examples, unless they were each set up exactly the same.

Hi Mark, Total Ink is set by the destination profile on the conversion to CMYK. If the editing is done in CMYK mode there is no total ink restriction, the profile doesn’t prevent you from using the problematic 100|100|100|100 fill.

You can make a conversion into a large gamut RGB space without an appearance change if you are willing to flatten the art. Then a conversion back to any CMYK space would limit the total ink and also keep the original appearance.

[m1b]

Hi Rob, yes that's a great broad approach, but without careful control I'd be worried about the final CMYK doc having slightly "dull" bands between the rich black and the orange center. It very much depends on the printing method but, for example, I'd wonder if the rich black should have more yellow to reduce the part of the transition between, ~95Y in the middle to ~60Y in the rich black. You are right that the destination profile might handle it well, in which case all is good, but I'd want to keep an eye on it. Do you get what I mean? Perhaps I am overthinking it? 🙂

- Mark

[rob day]

A flattened conversion of CMYK 100|100|100|100 to RGB should always return 0|0|0 RGB, doesn’t matter what the RGB destination is. To avoid the other CMYK color from changing appearance the destination should be an RGB space large enough to contain the entire CMYK gamut, or convert to Lab.

The conversion back to CMYK might produce the weak shadow transition you are worried about— a destination with a high TAC allowance like Coated GRACoL would transition well—SWOP at 300% not so much.

Try a flatten>ProPhoto RGB with Relative Colorimetric> Coated GRACoL 2013 on @cbishop01 ’s art to see the effect and measure the Black.

[m1b]

Hi Rob, I tried your process and I'm happy with the result! Thanks for walking me through it. 🙂

So, it looks like the best approach so far would be to use your conversion (if that suits the OP's TAC) as a batch action in Photoshop as mentioned by @Jens Trost.

[Jens Trost]

Hi there,
in my humble opinion the simplest way with the "best" outcome is to record an action in Photoshop, which reduces the layers, converts to RGB/Lab and then back to CMYK. [Edit]You could even leave it in RGB and do the CMYK conversion in InDesign, so you're safe for different CMYK outputs/profiles.[/edit] With that it's just one click within Photoshop.

Just make sure you keep the original.

+ Not a bridgeTalk() expert but I think you can automate that from InDesign so the link gets updated to the flatten image.

Or use batch processing via Bridge (I use Dr. Brown's Image Processor for Bridge on a daily basis).

Or if you're going to rip/print it yourself – maybe your rip has an option to reduce TAC. Some of them do, some require additional (costly) addons... 

[Eugene Tyson]

Only getting a chance to look at your file now

From what I see the 4 x 100% channels are the background layer

Why not do a batch action to turn off the background layer and apply a custom spot (see my first post on adding Spot Channels)

If you need help setting that up let us know.

[rob day]

but Total ink is what i'm trying to fix

Hi Eugene, I don’t think @cbishop01 wants to print a Spot plate, it’s just the TAC that needs fixing, so a flattened conversion to Lab or large gamut RGB would get rid of the 400% and keep the color appearance

[Eugene Tyson]

Ah right - then a batch action to add replace the background layer in photoshop would do it. 

Save to a different folder - and then relink to folder in InDesign.

That way it's not affecting any other colour in the image - right?

[rob day · Accepted solution]

That way it's not affecting any other colour in the image - right?

The layers above the black background are blending, so if you fill the background with a lower TAC it will affect the transitions and color appearance.Maybe no one would care, but try changing the black mix to something under 300% and you will see the change:

This is a classic example of why we shouldn’t edit in CMYK—it’s easy to violate the required TAC, and is the file really outputting to a US Web Coated SWOP press? There probably will be a color conversion somewhere.

[cbishop01]

Thank you so much everyone! I'm going to mark this as solved because there's a ton of good advise here.