Part 3 - Analog Proofing

Analog proofs are all produced by utilizing the film which also makes the printing plates. This ensures a high degree of accuracy, but doesn't allow proofing prior to the time-consuming and expensive process of producing film. Film can be used to produce multiple proofs, but this is only makes sense if the bulk of the proof is being done as a Dylux and a true color proof is needed only for certain sections. The most widely used forms of analog proofs are currently Dyluxes (also called blue lines), Matchprints, Cromalins, and color keys.

Dyluxes are single-color proofs composited onto a single layer. They are quickly becoming obsolete. Although relatively easy, quick, and affordable to produce, the limitations of Dyluxes are serious and digital options are even faster, cheaper, and easier. Color registration problems, and RIP faults can be caught, but because film has already been run, it is expensive to make changes and you're still left proofing color with a monochrome proof. Rarely used for "contract" proofs on full color jobs except for text-heavy projects such as magazines and some catalogs. Unlike the other analog methods, Dyluxes are created on specific stock and can't be made to reflect the effect of pre-tinted, matte, ultra-glossy, or other special stocks.

Matchprints and pressmatch systems are full-color proofs and are widely used. Each separated color film is exposed and laminated before the next is added. The resulting proof is bright, accurate, and among the most durable. The entire process (once film has been created) takes approximately ½ hour. The color range is roughly equivalent to a press (about 4,000) but may include colors that can't be replicated on the press.

Cromalin proofs remain popular despite the fact that colors vary from proof to proof. A Cromalin is created by adding CYMK toners in sequence to a sticky substrate. The operator peels a plastic covering from the substrate, exposing the sticky area, applies the toner, brushes off the excess, peels the next layer, applies the next toner color, and so on until each color has been applied. The process requires about 1/2 hour per plate. The advantage is a single layer proof and the ability to add specialty toners to replicate metallics and Pantone inks. Colors can be closely matched on a press, but proofs will vary from operator to operator due to the high degree of manual application required.

Color keys are excellent proofs for checking individual colors, but are neither as durable nor as accurately in registration as the other proofing methods. A color key is created by placing each color layer over the base, generally in the same order as followed on the press. Typically, color keys are bound on one edge only, enabling the proofreader to examine each color individually or in combination. This adds flexibility at the cost of registration accuracy. Colors can exceed press capabilities.

Analog proofs can only be created late in the printing process. The expensive, and time-consuming task of RIPping the files and outputting film must be done first. Any changes to the file will require the entire process to be repeated. Despite this, analog proofs are heavily used in the industry for contract proofing because of their superior accuracy.

Go to part 4 - Digital Proofing