Part 4- Digital Proofing

Digital proofing is still far behind analog solutions in acceptance among the printing industry, but digital solutions are improving rapidly and promise to eventually become dominate. The most obvious need for digital proofing solutions comes from the trend toward CTP schemes and digital presses, neither of which require the creation of film. Without the film, analog processes are impossible.

However, the potential benefits of digital proofing make it attractive even when analog solutions are available. Digital proofs can be much quicker to produce, require less skilled operator intervention, are consistent, and most importantly, can be incredibly cost-effective.

In essence, a digital proof is simply a printout of the file. Even the least progressive print shops have come to rely on digital proofing in the early stages of production. A mid-level color laser or inkjet printer can easily produce output that will serve as contract proofs for many jobs.

However, creating high-quality digital contract proofs that can rival analog solutions in fidelity is more difficult. The primary print methods for this level of proofing are dye-sublimation (dye-sub), thermal wax, and high-end inkjet printers. Color laser/copier output isn't as widely accepted due to its relatively poor color range and accuracy.

Dedicated digital proofing printers typically produce colors that more accurately reflect press capabilities and generally offer specialized pre-press features such as highly configurable halftone patterns, calibrated inks, and pre-defined press profiles. However, these solutions tend to be more expensive, use proprietary consumables, and often only work in combination with dedicated pre-processing hardware and software and may not support your specific press.

Non-dedicated solutions are extremely affordable, flexible, easily supported, and offer low-cost supplies. Ironically, their biggest drawback is their excellent output capability. In order to attract a large market, manufacturers can't ignore the majority of potential customers who will want to use the printer as a final output device. Therefore, it is essential that a non-dedicated printer be capable of producing output that matches monitor specs as closely as possible.

Both dedicated and non-dedicated printers are available in each of the three major categories, however, dye-sub and thermal wax solutions are currently the most common dedicated systems. Some of the major players in dedicated digital proofing market include CreoScitex, Kodak, Tektronix and Fargo in the dye-sub and thermal wax category and Epson and Hewlett-Packard for inkjets.

Dye-sub printers are capable of producing continuous tone photographs and can easily surpass the color capabilities of the press. The process involves converting the "ink" into a gas which can be mixed with other colors extremely efficiently. Dye-sub devices can reproduce halftone patterns, making them excellent proofing devices. The primary drawbacks are relatively high consumable cost and the need to use special coated stock (usually a glossy, bright paper), making it impossible to duplicate the actual press stock.

Thermal wax printers are similar to dye-sub, but fall just short of producing continuous-tone photographs. Additionally, output tends to have a waxy feel and heavily saturated areas can be shiny and prone to cracking. The advantages are low consumable costs and the ability to print onto a wide variety of stock, including many non-paper surfaces such as cloth or plastic.

Inkjet printers are becoming more and more popular as contract proof devices. The best inkjets produce near-photographic output. Colors tend to be somewhat subdued and washed out due to the nature of the technology and highly saturated areas can be prone to wrinkling. Advantages include high speed, low initial cost and medium consumable costs, high quality including the ability to produce halftone output.

Conclusions
Proofing has been a critical step in the printing process ever since the first customer refused to pay for a completed job. The quest for the perfect proof has continued ever since and remains just out of our grasp today.

The key to successfully buying, designing, prepping, printing, or getting paid for a print job is understanding exactly how the proof relates to the product. It is important to remember that the proof is only a tool to help in matching expectations to results. Like any tool, the skill of the wielder is vastly more important than the tool itself. Even the best proof, if not properly explained, can result in disappointment all around.

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