Ed #10 Prepress

The first proof you’re likely to see is a laser proof from a desktop laser printer. Although some laser printers can be equipped to accurately render color, most desktop proofs are used simply to check content. You can make sure that the copy and other elements are in the right place, and, if not, make changes at a minimal cost.

Image proofs, also known as random or loose color proofs, show only the printed images, without any other design elements. Are they the right size and cropped correctly? Do they match the original artwork? Is the color right? Are spot or customer colors reproduced accurately? If the image has been retouched, does it look as it should?

Bluelines, or single-color proofs, are made from the same film negatives or electronic file that will be used to image the plates or charge the image drum. Look for broken lines of type or other typographical errors. Check the pagination; make sure that any previous changes have been picked up. And when you are giving changes to the printer, make sure that all of the changes appear on a single blueline, not several different copies that need to be compared and reconciled.

As jobs get closer to the press, printers use a variety of proofing systems to simulate the color—and sometimes the dots—that will be printed. Composed proofs allow you to check for content, design and color. Make sure that all fonts, bleeds and crossovers are correct. Confirm that the right images have been used—and cropped correctly— and that large areas of ink coverage look smooth and rich. Watch out for moirés, and remember that they do not show up on monitors.

Contract proofs and press proofs are at the top of the proofing food chain. Contract proofs, also known as final proofs, simulate what the project will look like when printed, and once approved, become the standard for the press operator. Often, these proofs will be signed by the designer and or the client, and the person who does so takes responsibility for their quality and accuracy.

Off-press proofing systems are getting better all the time, but they are not perfect. It often remains difficult to accurately proof metallic inks, spot coatings or varnishes and fluorescent colors. It can also be difficult to predict the effect that colored or heavily textured stock can have on the appearance of the project.

As technology changes, so do proofing practices. But it is clear that soft, or monitor, proofing is the wave of the future. In the past, monitors could not be used for proofing, because they reproduce color differently than halftone printing. While monitors display images using the additive color process in red, green and blue (RGB) light, printing is produced using the subtractive color process, with cyan, magenta, yellow and black (CMYK) inks.

But now, with the help of special software, CMYK colors can be simulated on flat-panel displays. Printers, designers and their clients can calibrate their computers to produce virtually identical displays, and screen brightness can be controlled to simulate the brightness of the printed sheet. If a paper proof is required, users can calibrate desktop printing devices to match the printer’s press.

When the color is dialed in, the proofs are signed, and you are without questions, it is time to go to press. But that’s a story for another Ed—the next one, in fact (see Ed #11).