Step Three
A color plug-in for Adobe Photoshop offers a multi-channel preview within the app, to accurately display overprinting spot colors within images. This feature removes one of the largest historical limitations for Photoshop in packaging prepress. It could also provide tools to enhance the color gamut/appearance of images and make better color faster for all types of packaging.
RGB to EG
Expanded gamut printing allows color enhancement to images, but good flexography requires more than just adding additional inks. In many cases, great flexo printing requires reducing inks in some areas.
The following were the color separation steps used to create this flexo quality:
First, GMG ColorPlugin converted the RGB image to EG using a profile created by OpenColor, then ColorPlugin was used to perform these additional tasks.
A: Remove all cyan from banana (this keeps banana from turning green)
B: Remove cyan from strawberries (this keeps red from getting muddy)
C: Remove all magenta from green (reduce muddy greens)
D: Substitute orange for yellow in strawberries (makes red brighter)
E: Use black to control shape and detail in green leaves
F: Use black to control shape in yellow banana
G: Use black to control shape in red strawberries
H: Use orange to make red strawberries brighter
I: Use orange to make gradient in banana smoother
J: Use green ink to enhance the color of the green leaves
(Violet ink was not used on this image)
Converting an image to EG is only one step in the process. Without these additional steps, this image would not be as visually appealing, or as reliable and consistent on press.
The Ryerson study explains that there are many different colorant combinations that can make the same color in EG printing. For traditional presses, you can determine how to accelerate the speed of a press, or reduce the ink required for a color build. You can optimize a digital press color build to eliminate an ink that is not really required, and reduce a click. Or, you can use a color model that is more forgiving to drifts on a flexo press. The tool is also able to enhance the color of an image by converting directly from wide gamut RGB to the EG color space.
Step Four
The final, critical piece is a good proofing solution that can be easily adopted for EG. Although it is difficult to imagine significant improvements to the packaging world’s proofing technologies, the combination of the profiling software with proofing software has moved contract proofing to an entirely new level of color accuracy and press-to-proof match (complete with accurate rendering of spot color overprinting); hence, a wide adoption of this solution in EG already.
The tools that make up this process can provide a color and quality backbone for automated prepress workflows for flexo and other types of packaging. For example, it could be based on native PDF and open standards and support many third-party products, such as Colibri matchmycolor, MeasureColor, PantoneLIVE and others. Connections to ink formulation and pressroom process control systems can also be done.
End-Use Implications
This is a lot to claim or expect from any new technology, and customer expectations for EG are already high. But all of the technology described here is already being used in production, with exceptional results. Tight collaboration has overcome the limitations of earlier products and has put EG technology in the hands of flexographers worldwide.
Using this type of process, printers and trade shops report encouraging results:
“We have seen a dramatic drop in the need for additional rounds of color adjustment in our shop. With one of our customers, we have reduced color adjustment time from two hours down to 20 minutes. The plug-in has also been a game changer, allowing for individual layer adjustments (channel mapping, color combining) and profile-to-profile conversions on a layer-by-layer level. With the volume of EG work we handle, this has allowed us to increase productivity and efficiency,” says Tim Loehrke, color/comping manager at Schawk, a division of Matthews International.
Ron Rex, vice president of manufacturing at West Essex Graphics, reports, “West Essex Graphics uses many software tools and highly skilled prepress operators to produce the highest quality flexo plates for our demanding customers. We have seen an increase in customers who want to grow their print efficiencies, reduce washups and reduce usage of spot colors by moving to EG separations. When we learned there was an integrated solution to convert spot color designs into EG, we had to try it. Getting high-quality EG separations is not easy, but with the solution we are using, we were able to produce high-quality separations in minutes that were even better than any we had produced previously—and manually—in hours. We expect continued interest from our customers as they begin to see what is possible with EG, both in terms of increased quality and cost savings.”
Conduct your own research. Some questions the packaging printer may ask are related to cost: “Do I have to buy the whole server solution, or just a piece of software?” Other questions to ask are, “Is the vendor investing in ongoing development and color technology?” And, very importantly, “Does the product support color-accurate soft proofing?”
We think you’ll be pleasantly surprised at the results.
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