In our previous blog Print Blacks Right The First Time we discussed the basics of using a combination of CMYK to create rich black colors when printing.  Today we want to take things a bit further and talk about Total Area Coverage

Total Area Coverage

When there are several colors being printed on top of each other, as in when printing a rich black (c60 m40 y40 k100), there is a limit to the amount of ink that can be put on paper.  When designers ignore these limitations serious issues are caused on the press; For example, the last ink that’s laid down on the paper won’t attach properly to the previous layer leading to muddy colors in neutral areas and ink that won’t dry properly, then rub off on the sheet that’s placed on top.  This limitation is called Total Area Coverage (TAC) or Total Ink Coverage (TIC).

Total Area Coverage is specified as a percentage.  You get this percentage by adding up the percentage values used in each color, so using (c100 m100 y100 k100) would give you a Total Area Coverage of 400%.  The maximum that a printer will except will depend on several factors:

The printing process: Digital, laser, sheet offset and web offset each have their own limitations.

Paper Stock: Different papers will have their own limitations, this includes coated and uncoated.

Colors: The amount of colors being printed simultaneously will also affect intermediate drying times which will require limitations on TAC.

It’s always best to consult with your printer and discuss their TAC limitations prior to submitting work for print.

Here are the industry standards for Total Area Coverage

Commercial offset Printing: 320 – 340%

Heatset web offset (Magazines): 300 – 320%

Non-Heatset web offset (News papers): 240 – 260%

Inkjet Devices: 300 – 350%

Checking your TAC

To check the total area coverage of your design there are several options within Photoshop, Illustrator and InDesign.  Today i’m only going to discuss how to preview TAC on any file using Adobe Acrobat.

Start by exporting your files as a PDF.

Open the PDF using Adobe Acrobat and use the Output Preview option to preview the TAC based on your selected value.

In the example above we have taken the image on the left and used the Output Previewer on the right to highlight all the areas with a TAC higher than 300%.  As you can see Adobe Acrobat highlights in green all the areas with a total area coverage of  more than 300%.  If we refer to our industry standard we can see that this image would work fine if being printed on a magazine but could cause a potential over-inking problem if printed on newspaper.

In this case if we where planing on printing on newspaper we would adjust and reduce the black color percentages to meet the printing standards.  If we where planing using commercial offset printing we would adjust and increase the the black color values since we have more ink available to us to create a nicer rich black color.

If there’s one thing we can all agree on, it’s that the print press is merciless,  we’ve heard it time and time again garbage-in-garbage-out.  We’ve all had the painful experience before, the anticipation, hours of work, years of experience, how could anything go wrong, i’m a designer!.  Those final moments when that brochure your so proud of arrives at your doorstep, only to find you’ve dropped the ball, how could it be!

Even the best of us still feel that slight skip in the beat of our heart every time we submit a file to print.   Here’s a few things to think about before you submit any  file for production.

1. CONVERT ALL FONTS TO OUTLINE

I know, I know, you just gotta that Grilled Cheese BTN font on your next poster.  That’s great but unless your local printed has the same “beach side BBQ” taste in design, they probably don’t have the same font. Don’t believe it’s a problem, next time you have some free time on your hands, mosey on over to your font folder and hit delete, then start going through all your favorite text files, not a pretty picture.

Before you save the files your submitting to print, don’t forget to first flatten or turn your text to outlines.

In Photoshop you would flatten your layers, in Illustrator you would create outlines.

HOW TO FLATTEN AN IMAGE IN PHOTOSHOP

To flatten image layers:

1. Open your image in Photoshop
2. Click “Layer” in your upper menu bar and choose “Flatten” from the drop-down options.
3. Re-save the image

HOW TO CONVERT TEXT TO OUTLINES IN ILLUSTRATOR

To convert to outline:

1. Select the type object.
2. Choose Type > Create Outlines.

2. DESIGN IN CMYK

Now this isn’t a physics lesson on chromatics or color theory, but it is a lesson you’ll want to remember.  It’s important to note that your monitor doesn’t secrete ink to make the image you see before you, and that issue of seventeen magazine you just can’t seem to let go of, doesn’t have tiny light emitting diodes displaying your favorite teen hairstyle article.  When you design for ink, use the colors printers use: Cyan Magenta Yellow and Black, not the colors monitors use Red Green & Blue.

The Tale of RGB

Simply but RGB is an additive color mode, which means you add the Red, Green and Blue light into a black background ( like your monitor ) to get the colors you want.  The more light you add the brighter, or whiter, everything gets.  The problem is you can’t add colored lights to paper.

The tale of CMYK

CMYK is a subtractive color mode, which means you subtract light from your white piece of paper by adding more and more ink.  The more ink you add, the darker everything gets.

To help you visualize this a little better, think of the color black, if there is such a thing.  To make black in RGB, you would have to remove all colors, right.  To make black in CMYK you would add all the colors ( kind of, see our article on printing black ).

So basically RGB is for on screen colors, CMYK is for printing.  If you try and use RGB to print on paper, you’ll probably end up disappointed.

3. USE THE RIGHT RESOLUTION

Designing for web and designing for print can sometimes get us into trouble.  Things that look good on screen don’t always look good on paper, and things that look good on paper are usually to big (in files size) to place online.  Printers mostly print at about 300dpi, that’s 300 dots per square inch.  Your monitor on the other hand has a resolution of 72ppi, that’s pixels per inch.

Ok now don’t go crazy trying to find the dpi setting on your favorite design program, there isn’t one,  monitors have pixels, ink makes dots .  Pixels are square and dots are… dots.  Printers will translate 1 dot per pixel, so it’s basically the same thing

For the most part when you are designing for print be sure to design at no less than 300ppi, more is ok, but never less.  Ask your printer what ppi to design your particular project before starting,  Once you start, trying to convert up to 300ppi will cause a loss of quality.