The Fine Art of Color Proofing

Previous articles in this series about printing have discussed the basics of prepaid card production and the design process. Part III covers the importance of the proofing process.

Once a design is determined, there can be numerous rounds of revisions including reviewing and editing copy, content review and color changes. The number of rounds of revisions varies based upon how many people need to review and approve the design and the design's complexity.

Revisions should be made by all approving parties before proceeding to the proofing stage - the next step in the print production process.

A proof is the most accurate way of representing how the design will actually print without actually printing the piece. There are numerous types of proofs. Blueline proofs do not show color (they are generally blue), but they do show position, size and type. Bluelines are often used for designs that will be printed in only one or two colors.

For prepaid card production, the most commonly used color proofs are film proofs (proofs generated by film) or digital proofs (proofs generated without film). The popularity of digital printing and digital proofing has made proofs generated by film almost extinct. Regardless of which proof method is selected, if the design includes photographs of colors that need to be matched, a color proof should be mandatory. The additional cost of a color proof is good insurance against receiving an unusable print job.

A new trend is viewing color proofs via the Internet or e-mail. Electronic graphic files are converted into JPEG files that can be posted to a secured Internet site or sent via e-mail. Viewing color proofs this way is great for mock-ups or checking that revisions have been made, but should not generally be used as a final color proof. Printing methods will be covered in a future article, however, in order to understand the accuracy (or lack of accuracy) of a color proof, a general understanding of color and how it is viewed is required.

Print production colors are created using inks based in CMYK - cyan (blue), magenta (pink), yellow and black.

The printing process uses these four process colors in a small dot-like pattern to create the appearance of virtually millions of different colors. Look at any color picture in a magazine under a very strong magnifying glass and you won't see colors like brown or purple, instead you'll see little dots of CMYK that give the appearance of different colors when combined in the right patterns.

CMYK is great for printing designs that utilize photographs or colorful graphics and special effects.

However, for simple designs or when colors need to match exactly, most designers will specify a PMS color. PMS stands for Pantone Matching System - the industry standard in mixing ink colors for exact match.

PMS colors have a number designation. For example, PMS 186 is red, but a red with a slight orange tint. Just like in a paint store, the Pantone Matching System publishes color swatches in books that fan out. Designers look through the book to pick colors and then designate specific PMS colors to utilize in their designs. Many corporations have specific PMS colors designated for their logos and want that color used in all printed pieces. In some cases, designs may require both CMYK and PMS colors. A common application is a photograph printed in CMYK combined with a corporate logo printed in a PMS color.

Because print colors are based on CMYK or PMS colors, viewing a color proof via the Internet or e-mail is not going to be accurate. Video monitor colors are viewed in RGB - red, green and blue and are based on light principles, not on ink/pigment principles. Therefore, colors that appear on the screen can be very different than the printed version. Files that are originated in RGB can be converted to CMYK by a color specialist, and files can even be altered to somewhat match, but it is virtually impossible to get an exact match between RGB and CMYK. Because of this, viewing a color proof via the Internet or e-mai is best used for what is called "soft-proofing," to determine if the design and text are correct, but not be used for color approval.

Most vendors call the final color proof a contract proof, meaning that the sign-off on the color proof is a contract between the priner and the client for proceeding with production, and the final product will be accepted by the customer based upon the approval of the color proof. Color proofs are expensive and time consuming, so it is important to have the file as close to final as possible. If changes are needed after reviewing the color proof, there will probably be additional costs and time delays. Most printers will not guarantee a print date or a delivery date until a final color proof has been reviewed and signed.

Every printer has a different quality control standard regarding color. The amount of tolerance for color variation from the customer-approved color proof depends upon the proofing method, type of printing and print stock. Some larger-volume printers have color control specialists on staff to monitor color variation and to help the press operator achieve the best match possible. If colors are extremely important to match, the order is sizeable and the project is high profile, the best way of assuring a quality print job is to conduct a press check.