Fixing ink coverage errors for print-on-demand providers like IngramSpark

Recent­ly, I had trou­ble get­ting IngramSpark to accept cov­er art for The Noth­ing With­in. They kept send­ing it back with this error message:

 CMS__Title_Processing_Error

Rea­son: cov­er : INK COVERAGE EXCEEDS 300% CMYK ON THE COVER

Sol­id areas of col­or on the cov­er exceed 300% CMYK. This will cause print­ing prob­lems such as streak­ing, spot­ting, and cracking.

This was espe­cial­ly puz­zling because the pre­vi­ous week, they accept­ed the same cov­er. The cov­er text had changed in the inter­im, but noth­ing had changed about the cov­er art or its col­or profile.

Many peo­ple work­ing with Print-On-Demand (POD) ser­vices have this prob­lem. Unfor­tu­nate­ly, though IngramSpark gave a rea­son­ably detailed descrip­tion of the prob­lem, they offered no advice on resolv­ing it.

Here’s how I worked around the prob­lem. This post assumes you have access to Pho­to­shop (the full ver­sion, not Pho­to­shop Elements).

What went wrong?

Large areas of the cov­er art required too much ink. That might have led to qual­i­ty prob­lems. Specif­i­cal­ly, large area exceed­ed 300% Total Ink Cov­er­age (TIC), also known as the Total Area Cov­er­age (TAC).

300% ink coverage? What does that even mean?

Most com­mer­cial print­ers cre­ate col­or images with a com­bi­na­tion of four inks: cyan, magen­ta, yel­low, and black (CMYK).

If you print some­thing pure yel­low, that’s 100% yel­low (Y=100). That’s 100% total ink cov­er­age.

If you print some­thing pure green, that’s 100% cyan (C=100) and 100% yel­low (Y=100). That’s 200% total ink cov­er­age.

When you make a Pho­to­shop doc­u­ment that uses CMYK col­ors, by default it uses a col­or pro­file that allows for up to 300% ink cov­er­age. That works fine for many com­mer­cial press­es that print on spe­cial­ly coat­ed paper. But some presses—for exam­ple, news­pa­pers and POD ser­vices like IngramSpark—have a low­er limit.

In IngramSpark’s case, their cus­tomer ser­vice team shared this with me:

Although our rec­om­mend­ed max­i­mum is 240%, we can accept TAC (total area cov­er­age) up to 300% for most cov­er files, espe­cial­ly if the 300% area is not a large area.

In my case, the prob­lem was caused by large, very dark areas of the cov­er art.

Why did they accept and then reject the same cover art?

Because human judge­ment is involved.

Here’s what I’ve learned about IngramSpark’s POD art accep­tance process. I’ve learned this not from IngramSpark, but from oth­er arti­cles and blog posts, some of which are linked at the bot­tom of this post:

• Human review. This isn’t an auto­mat­ed process. A tech­ni­cian does a final review of the cov­er before print­ing. (That’s a very good thing.)
• Vari­abil­i­ty. Dif­fer­ent tech­ni­cians might make dif­fer­ent judge­ment calls. (That’s a less-good thing, but worth it in exchange for human review.)
• Wig­gle room. They’re not com­plete­ly strict about the lim­its. It might be okay if only small, iso­lat­ed areas exceed the limit.
• Art type mat­ters. This is main­ly an issue for art that has large, flat dark areas. Art with more grad­ual col­or changes, like pho­tos and paint­ings, is allowed to have a 300% limit.

Okay. So how do you fix it?

Every print­er, ser­vice provider, and cov­er is different.

Your first option should be to con­tact your print ser­vice provider for tech­ni­cal support.

WARNING: I’m not a print­er or CMYK expert. I’m just some guy who does­n’t mind googling and tri­al-and-error. What worked for me might not work for you.

But hav­ing said that—my cul­prit was the col­or black.

Um…what? The color black?

Yes.

The col­or black.

Let’s say you print some­thing in black like this:

• C=0
• M=0
• Y=0
• K=100

You won’t real­ly get black. You’ll get some­thing more like a dark gray. That’s because the black ink isn’t all that black.

To address this, design pro­grams like Pho­to­shop, Illus­tra­tor, and InDe­sign use some­thing called rich black. Rich black is the black ink with some col­ored inks added. That makes the black look richer.

Since I’m using Pho­to­shop, I’ll use that for my exam­ples. Here’s Pho­to­shop rich black:

• C=75
• M=68
• Y=67
• K=90

Oops!

That rich black is (75 + 68 + 67 + 90) = 300% ink cov­er­age. That’s because most design pro­grams begin by assum­ing you can go to 300% ink coverage.

The actu­al­ly-col­or­ful parts of my cov­er were fine. The prob­lem was that my blacks were too black. I need­ed to use IngramSpark’s rich black:

• C=60
• M=40
• Y=40
• K=100

So just using that version of black in Photoshop will fix it, right?

Nope.

Because some­times, lay­ers in pho­to­shop can dark­en lay­ers below them.

Imag­ine you have some­thing that’s at exact­ly 240% ink cov­er­age. Now you lay­er some­thing on top of that with a drop shad­ow. The drop shadow—no mat­ter how light it is—will dark­en the lay­er below. That means more ink dur­ing printing.

Can I just tell Photoshop to limit ink to 240%?

Absolute­ly, that’s one solution.

1. Edit > Con­vert to Profile
2. Des­ti­na­tion Space Pro­file: Cus­tom CMYK
3. Ink Col­ors: SWOP (Coat­ed)
4. Change the total ink lim­it to 240%

But when I did that, some col­ors got bad­ly desaturated—blue in particular.

Okay. I’m sick of guessing. How do I fix it?

Yeah. I was sick of guess­ing by this point, too.

The approach that final­ly worked for me focus­es exclu­sive­ly on black. Specif­i­cal­ly, I want to pull those CMYK lev­els down from Pho­to­shop’s rich black (75/68/67/90), so that they’re no high­er than IngramSpark’s rich black (60/40/40/100).

If your image began as an RGB doc­u­ment, you’re ready for the next steps. (You can check at Image > Mode.) But if you began with a CMYK doc­u­ment, it’s best to con­vert to RGB and then con­vert back to CMYK. As explained by IngramSpark cus­tom support:

A sim­ple way to ensure that the TAC does not exceed 300% is to con­vert the final file to RGB and then back to CMYK. This is not ide­al for every­thing, but can work for back­ground images that are more complicated.

So now the whole doc­u­ment should be under 300%. We need to tar­get the large, dark areas to get them to 240%.

First, you need to change the Info pane so that it shows total ink sat­u­ra­tion for what­ev­er pix­el is under your cur­sor. To do this:

1. Show the Info pane. Win­dow > Info
2. Go to its Pan­el Options. In the upper right cor­ner of the pane, like this:
   
3. Show total ink. Set the Sec­ond Col­or Read­out mode to Total Ink and click OK.
4. Try it out. Now, wher­ev­er you point your cur­sor, if the doc­u­men­t’s col­or mode is CMYK (see below), the Info pane will show that pix­el’s ink cov­er­age. You’ll see the ink lev­el for each of the four col­ors, as well as the sum of those lev­els shown as a Sig­ma on the right, like this:
   

Now, let’s fix the image.

1. Work on a copy. Open your PSD file and save a copy as (name) CMYK.psd
2. Merge all lay­ers. Select all lay­ers,  then Lay­er > Merge Layers
3. If it’s not already, change the col­or mode to CMYK. Image > Mode > CMYK
4. Pre­pare to desat­u­rate. Image > Adjust­ments > Selec­tive Col­or > Col­ors: Blacks

Next, fid­dle around:

1. Move your cur­sor to the dark­est part of the image
2. Look at the Info pan­el; we want to get that Cyan num­ber down to or below 60%
3. Pull the Cyan slid­er a lit­tle to the left (try ‑25% to start)
4. Put your cur­sor over that same dark spot again, and check the Cyan lev­el in the Info pane
5. Once you get Cyan to be right around 60%, do the same for the oth­er col­ors: Cyan 60%, Magen­ta 40%, Yel­low 40%—what worked for me was ‑25%, ‑50%, ‑50%
6. The image prob­a­bly looks real­ly pale right now, so increase the Black until you like it (20% for me)

Once it looks good, click OK.

I end­ed up with an image that was­n’t exact­ly like the orig­i­nal, but real­ly close—much clos­er than with the half-dozen oth­er meth­ods I tried.

How can I confirm the image is okay?

Option 1: Submit it to your printing service

If they accept your image, it’s okay. But this option adds turn­around time.

Option 2: Photoshop, one pixel at a time

Use the tech­nique above with the Info pane to check the doc­u­ment. Not every pix­el, of course, but spot-check as many prob­lem areas as you can stand to.

Option 3: Actrobat Pro

If you have access to Acro­bat Pro, life is way easier.

1. From Pho­to­shop, save the doc­u­ment as a PDF
2. Open the PDF in Acro­bat Pro
3. View > Tools > Print Production
4. In the right-hand side­bar, click Out­put Preview
5. Near the bot­tom of the dia­log, check Total Area Cov­er­age and enter your tar­get ink val­ue (240 in my case)
6. Acro­bat shows an awe­some map of over-cov­ered areas, high­light­ed in bright green, like this:
   

Links to related posts and articles

If that method does­n’t help you, here are some oth­ers that might.

• Cor­rect­ing Com­mon Print Errors — One­Book­Shelf (2016)
• IngramSpark’s require­ment for jackets/covers for POD books — When Clouds Fell (2015)
• Force Col­or Images to CMYK with a 240% Ink Lim­it — InDe­signSe­crets (2014)
• More on Total Ink Lim­it — New Self-Pub­lish­ing (2013)
• Reduc­ing the total ink lim­it in CMYK images using Pho­to­shop — Cre­ative­Pro (2013)
• Liv­ing With­in Lim­its: How to Deal with Light­ning Source’s 240% Total Ink Lim­it — New Self-Pub­lish­ing (2011)
• Under­stand­ing ink lim­its in Pho­to­shop — The Graph­ic Mac (2010)

Image cred­it: Don­nie Ray Jones (mod­i­fied to include CMYK bubble)