One of the key ingredients to success in digital printing is good color management. The most critical element in color management is understanding and proper use ICC Profiles. Using the wrong profile can cause unwanted color shifts, excessive ink usage, and production problems. What is an ICC profile, how does it work, and how does it affect print quality?
What is the ICC Profile Function?
ICC stands for International Color Consortium, an industry group devoted to standardizing color in commercial printing applications. An ICC profile is an element in RIP (Raster Image Software) software that allows the software to coordinate the physical attributes of your printer, print head, ink, and media to obtain correct and consistent color. ICC profiles contain several elements including rendering intents, dithering patterns, ink levels, etc. There are input and output profiles. We’re dealing with output profiles here which are designed to control the quality of the images you output to your digital print devices. Each printer has unique properties that affect how it puts ink to media. The type of print head, number of nozzles, and size of the ink droplets are all factors that the software must take into account in order to optimize the speed or quality of the output. In addition, different media have varying properties including their ability to absorb ink and control dot gain. These too must be factored in. All of these variables are managed in the ICC Profile. Your job is to manage the profile by selecting the right one for the media you’re using. Since eco-solvent printers use heat to facilitate penetration of ink into the face film, profiles used for these printers also take into account the optimal temperature for a particular media and/or the specific heating system of the printer. The MUTOH profiles found in Flexi Sign & PRINT 19
and LXI RIP 12
allow users to include the optimal temperatures of the printer’s heaters. Unless the printer is jump started, it will not begin printing the job until the heaters are all at the correct temperature. You can force the printer to start before the heaters are at the right temperatures, but doing so overrides the ICC settings and may result in an apple pie with half a crust. How important is it to pick the right profile? That depends partly on the hardware. For older printers, it’s absolutely essential. Some of the features mentioned above are dependent on advances in printer technology. Older output devices aren’t as sophisticated and need more careful color management. MUTOH’s patented wave print firmware makes correct profiling a little less critical by hiding banding and making dithering patterns less visible. But even with the I2
(wave printing) firmware, differences can be seen from one profile to another. When we added our PrismJET WallTEXTM
adhesive fabric, we made a large sample for the training room using a photo of a boy playing soccer. But the flesh tones were too saturated. So our product support staff created an ICC profile for the new media. Now the flesh tones are perfect and our WallTEXTM
prints are of magazine quality. We've also recently created new profiles for our 6-mil, semi-rigid PrismJET 220, 221, and 222 matte and glossy printable vinyl. We offer high-quality profiles that maximize print quality and high efficiency profiles that offer vivid color and faster print speeds. Generally for each custom SIGNWarehouse media profile, you'll find both options.
Signs of Incorrect ICC Profiles
How do you know if it’s “right?” As the old adage goes, beauty is in the eye of the beholder. Color is subjective, so trying to determine when a print is perfect is harder than it sounds. In a production environment, the more practical approach is to look for problems that indicate incorrect color management settings.
FIG 1: Same image file, same printer, same ink: different profiles
In addition to noticeable color shifts, these include over-saturation, insufficient ink coverage, edge curling and drying problems. Edge curl and excessive drying time can be signs of over-saturated prints. Too much ink may cause edge curl, especially in full bleed contour cut decals. In addition to causing production issues from too much ink in the media, over-saturation wastes ink and money. Excessive drying or curing time can cause production delays which also cost money. If you see these issues cropping up, check the profile. If it’s not the right one for the media you’re using, get the right one. Using a profile that matches your media will result in correct color, crisper images, and optimal drying times.
Where to find ICC Profiles
All good RIP software comes with a basic package of ICC profiles, print modes or imaging configurations. RIP software for large format printers generally includes profiles for the leading brands of media including Avery, 3M, Oracal, etc. So the first place to look is in your software package. If the profile you need isn’t there, you’ll need to add it. If you’re using a PrismJET VJ54,
or MUTOH ValueJet, start at the SignWarehouse Support Blog
and click on PrismJET printers section, then scoll to the PrismJET Downloads section and click download profiles. Or just click here
to download them all. All of our custom profiles are made using EnduraINK PRO ink to ensure optimal print quality and cost-efficiency with our ink. If you don’t find what you need there, you may contact SignWarehouse tech support or search online. Most inkjet media manufacturers offer profiles for their product for the leading brands of RIP software. If you download from a manufacturer’s website, make sure you get the right one. An Onyx profile is of no use to someone using FlexiSign. If there isn’t one available, use one for the media that’s most similar to yours. For instance, if you’re using an intermediate calendared matte vinyl, select an ICC for a different intermediate calendered matte vinyl.
Firmware and Software
As noted above, the ICC optimizes the relationship between the hardware, software, media, and ink. If any of these elements change, it may require updating the ICC. Flexi 19 is a good example. SAI replaced SO Diffusion with enhanced stochastic as the default dithering pattern in Flexi19. Converting old profiles to the new standard caused some color management issues, so we built new ones. You'll see the link for those on the Printer Profiles page right under the VJ54 profiles. Occasionally, the most basic ingredient can be thrown off by a subtle change. The hardware driver is based in part on the printer’s internal software package known as firmware. A firmware update can recalibrate the print head enough to throw your previously perfect profiles into disarray. It’s rare, but it can happen. If your prints have taken a sudden drop in quality or color accuracy and you haven’t changed anything else, ask if there has been a firmware update on your digital printer. If so, you may have to request or create updated profiles to bring the formula back up to snuff. Of course you could just ignore all this bother and use a generic profile for everything you print. But then you run the risk of delivering your customer an apple pie with no crust. It might be tasty, but it’s not quite right. Or it may look great, but waste ink, time and money due to over-saturation. In a competitive market delivering correct color and avoiding wasteful inefficiencies can make the difference between winning customers and losing sales. WWW.SignWarehouse.com