Internet, Networking, & Security Web Development Digital Proofs Prevent Printing Snafus By Jacci Howard Bear Writer A graphic designer, writer, and artist who writes about and teaches print and web design. our editorial process Jacci Howard Bear Updated March 15, 2019 Yuri_Arcurs / Getty Images Web Development Web Design CSS & HTML SQL Tweet Share Email Proofs that are made from digital files rather than run on a printing press are digital proofs. They have the advantage of being less expensive than press proofs and faster to produce but—with some exceptions—the results cannot be used to judge color accuracy. There are several types of proofs that can be made from digital files. Some are rudimentary and some are highly accurate. Types of Digital Proofs Onscreen proofs. The simplest type of digital proof is an online soft-proof. This WYSIWYG monitor proofing is only used in the early stages of production, usually by the graphic artist.Desktop laser or inkjet proof. Printing a digital design file to a monochrome or color desktop printer shows element position, possible type problems, and art placement. It does not represent color accuracy. This stage of digital proofing is usually used by the client or graphic artist.A PDF is a type of soft proof made from a client's electronic files by the commercial printing company and sent to the client for review. It is not used for critical color work.Bluelines (also called dylux) are used to judge that the pagination—the order of pages in a book for example—is accurate. This step occurs at the commercial printing company in its prepress department after the job is imposed for print. Bluelines were originally printed from imaged film that was eventually burned onto plates for the press. The inexpensive paper that produced the proof delivered only a blue image for proofing—hence its name. As the film has phased out of the prepress process, large monochrome or color printers print the imposed electronic file in onto inexpensive white paper, but the original name remains. The proof is backed up and folded to demonstrate the correct imposition. It is not color accurate.High-End Color Digital Proofs. A high-end digital color-accurate proof is a prepress proofing method in which a print job is imaged from the digital file to a highly accurate inkjet, color laser or other print technology printer to give a close approximation of what the final printed piece will look like coming off the press. The digital proof is much less expensive than the press proof it replaced. Improvements in color management technology allow digital proofs to serve as contract proofs. Contract Proof Is a Legal Agreement A high-end color digital proof that is considered accurate for predicting the content and color of a print job when it comes off the press is a contract proof. It represents an agreement between the commercial printer and the client that the printed piece will match the color proof. If it does not, the client is in a legal position to request a reprint at no cost or refuse to pay for the printing. What Is a Press Proof? Before color management technology became as sophisticated as it is now, the only way to produce an accurate color proof was to load the printing plates onto the press, ink it up and run a copy for the client's approval. While the client viewed the press proof, the press and its operators stood idle. If the client didn't approve the proof or requested changes to the job, the plates were pulled from the press (and eventually remade) and all of the time spent on setting up the press was wasted. For this reason, press proofs were expensive. Affordable color-accurate digital proofs have replaced press proofs as the preferred proofing method for most commercial printers and their clients.