By Olivia Cahoon
The need for accurate color is increasing as print buyers become educated, color standards evolve, and new media types are created. Print service providers (PSPs) can better control color by investing in the tools and practices of an end-to-end color managed workflow.
Color management is an all-encompassing process that includes tools from RIPs to spectrophotometers and light viewing stations. The road to managing color begins in prepress and continues into printing and finishing. Certain practices and tools are more important than others during this process, depending on the end user, job, and PSP’s objectives.
Above: The X-Rite i1iO Automated Scanning Table enables hands-free test chart reading to aid in color management.
Color’s Top Standards
Several top standards are expected when it comes to color management. This depends on the region, industry, and technology used.
Standards for color management were not historically or widely practiced in wide format. Competitive environments forced PSPs to focus on color and quality output, especially as print buyers became increasingly aware of color management standards for color output accuracy, says Jonathan Rogers, international marketing manager, Onyx Graphics, Inc.
Today’s standards for color management include FOGRA, G7, GRACoL, and the recent announcement of ISO standard iccMAX. The International Colour Consortium (ICC) is technically the governing standard for color management. According to Don Hutcheson, president, HutchColor LLC, G7 is the most popular specification for printer calibration although it is not yet a true standard. GRACoL is the most common Characterized Reference Print Condition, which determines the intended appearance of a CMYK file.
“Both GRACoL and G7 were originally created for offset lithography but apply equally well to any other type of color printing, and in fact are the glue that provides shared appearance between different printing systems,” explains Hutcheson.
PSPs select which standards to use depending on the print application or job location. For example, Rogers says what is important for PSPs in the Asia Pacific region may not be the same as in Europe or the Americas. GRACoL is popular in the U.S. while FOGRA is favored by European-based companies.
Media selection also influences color standards. “The influx of new and exciting media types means providers must include the ability to dial in specific color settings to ensure superior, accurate, and consistent color output. Color management tools must adapt to support output across all media types,” shares Rogers.
While more print buyers demand and expect PSPs to use top standards, PSPs also opt for them to achieve pleasing color. “The key is to have all the tools at your fingertips to achieve both and the most important thing is repeatability. Even if you have achieved customer satisfaction and a sign off, you need to ensure that you can reprint a job on any given day, and even if it is months or years after the original job,” notes Chris Schowalter, director market segment management, EFI Fiery.
Prepress & Proofing
Color management begins in the first stages of the print production process in prepress and proofing. Several color management tools are used such as color servers and RIP software.
In a best-case scenario, color management starts even earlier than prepress with a designer selecting colors based on achievability. According to Ray Cheydleur, print, packaging, and imaging portfolio and market manager, X-Rite Incorporated, the Pantone color bridge book is a common tool many designers use, which was recently updated to show the results of Pantone colors using CMYK in a press run based on G7 calibration to GRACoL coated and uncoated profiles.
In prepress, color management starts by selecting the proper equipment and material. “Ensuring you have the same hardware—measurement device, printer, and light box—and as consistent a consumable as possible will go a long way in ensuring repeatable results,” shares Schowalter.
He believes prepress setup in regards to color management typically follows as linearization, ink limiting, media profiling, possibly iteration/optimization of color match, spot color control and iteration/optimization if required, setup of automated workflows including preflight if possible, and setup of process control through scheduled color control measurements and cloud reporting.
PSPs can also consider the five “Cs” of color management. Mark Geeves, director of sales and marketing, Color-Logic Inc., says this includes calibration to bring a printing device to a known state, characterization commonly associated with an ICC profile, control and the use of process control, color communication that can only occur if the previous three Cs are completed, and continued development as it relates to new instruments and software to make the process simpler and automated.
“Calibration and control of your process are critical. This way all of your production at least looks the same,” offers Greeves.
Another consideration is establishing a baseline and process for dealing with input files such as customer artwork to account for a mix of RGB and CMYK images and embedded profiles. “Ideally, the RIP or workflow in use can manage this, and it is important to understand the tools available and to set them up correctly,” adds Mark Gallucci, technology marketing manager, Agfa.
Color management tools used during the prepress stage include workflow, centralized color servers, and RIP software.
Prepress workflow addresses two needs—preflight to ensure that file and color definitions are proper and high grades of automation that reduce touch points. According to Schowalter, a centralized color server is also used in case the output devices do not have sophisticated color management functionalities.
RIPs are also important. The software offers many features beyond driver level support and can help control calibration and provide multicolor ink support, ink limiting, and intelligent ganging of work/jobs. “These are all things busy print shops need to do,” comments Cheydleur. “Using RIP software in combination with the proper proofing tools, spectrophotometers, and digital color libraries, means printers can start to get first shot off the press matches and quality results.”
The Printing Process
After prepress, the next step in an end-to-end color management workflow occurs in the printing process with calibration, the use of spectrophotometers, and validation.
In a full ICC profile workflow, the color management steps are similar for any printer. Cheydleur notes that specific settings vary based on particular printers and the associated driver or RIP implementation.
The first step in the printing process is to turn off any built-in color management features and to calibrate the production device either with a built-in spectrophotometer or a separate tool. Cheydleur then suggests printing a profiling target compatible with the device that the PSP will measure with.
PSPs should then ensure the target printed. “It’s important to note that this step doesn’t require standardized lighting as this isn’t about absolute color fidelity but rather mechanical reproduction quality,” says Cheydleur.
Once a satisfactory print is achieved, PSPs can measure it with a spectrophotometer. This is needed to calibrate the relationship between the printer, media, and ink set. “When your print recipe is calibrated, you can start producing something and at least be able to match the color expectations,” explains Michael Dreher, strategic and technical partnerships director, Caldera.
According to Peter Pretzer, ColorPath Solutions development manager, Fujifilm North America Corporation, Graphic Systems Division, a spectrophotometer capable of multiple measurement modes such as M0, M1, and M2 is desirable. These can be handheld devices with an integrated color computer or a tethered device that can also be attached to a robotic arm for automated chart measurement.
“For creating profiles and calibrating printers, spectrophotometers are needed. Spectrophotometers and spectral data are indispensable to obtain accurate, reliable, and repeatable color quality on many types of printed output,” agrees Thomas Nielson, technical sales manager, Color Concepts.
Inline spectrophotometers are also available on today’s proofing engines and offer a high degree of automation despite limited functionality. “Automated chart readers are also useful for quickly measuring multiple charts in larger numbers,” adds Pretzer.
The final step in the printing process is validating the resulting proofs and digital prints by checking a control strip using quality control workflow software. “With a color management process in place, a printing operation will have an end-to-end color managed workflow that helps reduce waste and rework, as well as improved profitability and customer satisfaction,” offers Cheydleur.
Final Print & Finishing
The final steps in the color management process occur during the final print and finishing process. This stage represents how color is viewed and includes tools that allow PSPs to control lighting.
In the final stages of the finished product’s evaluation, color management typically ensures that the visual result matches the original customer specifications such as brand color, manufacturing tolerances, and appearance expectations in the final end user environment, reveals James Summers, VP, JUST Normlicht.
“Controlled, color-critical viewing conditions are an essential component of this evaluation system,” continues Summers. Graphic arts color management workflows use the CIE D50 reference illuminant as the standard, also referred to as 5000 Kelvin. Most steps in the color management workflow conform to or assume the use of D50.
When an item is viewed, the color displayed is a combination of the light source’s color quality and the item’s reflective characteristics. As a result, when attempting to achieve an accurate color match, colors can appear to match under one light source and then appear significantly different under another. “Therefore, designers, brand owners, and production staff should all evaluate a color under a consistent light source,” suggests Brian Wolfenden, field marketing manager, GTI Graphic Technology Inc.
To achieve this goal, industries have developed international standards for viewing color. The graphic arts and photographic industries adopted ISO 3664:2009, which specifies the D50 viewing conditions and requires that viewing conditions meet strict specifications with regard to color quality, light intensity, evenness of illumination, viewing/illumination geometry, and surrounding conditions, explains Wolfenden. “Differences in any of these conditions may affect color appearance.”
Light viewing stations and light boxes are available that offer ideal viewing conditions. However, not all end use environments offer the perfect lighting, especially in the point of purchase space. Summers suggests sophisticated customers and PSPs measure and quantify those conditions. Systems are available that can be configured to the end user’s environment. “The goal is both to see the appearance in the end user environment and to see the metameric failure—the change of color appearances due to changes in the viewing light source.”
“If the product has many copies, consistency is achieved by evaluation of every Nth copy by pair comparison method in a light booth. If a product has parts printed separately, the final product state should be evaluated and their parts matched closely in the light booth,” adds Nielson.
Lastly, PSPs should consider how the finishing process affects color. Cheydleur says this includes applied laminates, varnish, coatings, the dye-sublimation process, and the type of backlighting used.
Not all PSPs require full color management from end to end, especially using all of the tools and steps previously noted. Some PSPs prefer a simplified workflow while others may want to invest in the full color management process. Deciding which solution is best for a print shop comes down to the PSP, the end user, and the job.
“It really all depends upon what the customer wants,” shares Marc Levine, director of business development, GMG. For example, if a customer supplies artwork from an unknown source in an unknown color space, making precise color reproduction becomes a matter of interpretation. “Many brand companies spend a lot of money on design and a standardized process to ensure that color is accurately communicated and those companies typically require consistent and specific color.” In those cases, a fully color managed workflow is critical.
It’s up to PSPs to decide who the customer is and what requirements they need. Color management often comes down to either serving customers with non-critical needs where pleasing color is good enough or deciding to serve color-critical customers. According to Levine, this helps PSPs setup their workflows and color management processes.
Regardless of the customer, PSPs need some collection of tools to rely on and determine if their products achieve the color quality they committed to the customer. In Summers’ opinion, the required tool level depends on the customer, the PSP’s workflow, the imaging of printing technologies, product and substrates in use, and the variability of each process in the entire product flow. “A skilled color management consultant can assist in such an evaluation.”
PSPs that don’t adopt internal color management must either rely on external color management service providers or limit themselves to digital presses with built-in automated color management systems, otherwise they may lose work to better-equipped PSPs, admits Hutcheson. “The cost of proper tools, software, and training to implement full internal ICC color management is quickly paid back with higher quality and efficiency.”
In select situations, PSPs may opt for color management for one piece of the print puzzle. For example, Cheydleur suggests PSPs printing to one device and using the same device for proofing could limit color management to that device by calibrating and profiling. “You wouldn’t gain all the advantages of an integrated workflow but you would reduce surprises and waste,” he explains. Once a PSP adds additional steps or output devices the need for a more complete color managed workflow increases.
Competitive environments require print providers to focus on color and quality output, especially as end users become more aware of color management standards such as FOGRA, G7, GRACoL, and iccMAX. “Print buyers need to know their PSP can provide accurate, consistent color that conforms to these standards,” shares Rogers.
By utilizing the latest color management tools and implementing best practices, PSPs achieve reproducible results that prove their color output is the same today, yesterday, and into the future.
May2020, Digital Output