G7 Revealed: Interviewing a Color Expert


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G7 Revealed: Interviewing a Color Expert
Because learning more is always better

By Noel Ward, Editor@Large

Offset printing has set expectations for printed color pretty high. Meanwhile digital color, since creeping into the market in 1993, has received its fair share of abuse, considered at best a pretender to the throne. Yet nearly every successful print shop now has both technologies under its roof, claiming both are essential to success. But getting digital and offset color to play well together has been difficult. Comments from some offset die-hards illuminated the differences and challenges: “Huh. You can tell it’s toner. It behaves like toner,” or “It looks OK,” there’s always a pause, “for a digital print”

For years there has been little doubt that color—and controlling it— are the most omni-present topics in all of printing. And with good reason. Color is critical to the appearance of every printed piece and is especially important for branding. It has to be right, and your job as a printer is to make sure colors are correct. One way to do this, according to a study done in 2019 for Canon by NAPCO Research, is controlling color so it matches expectations. In the study, about two thirds of print buyers prefer G7® certified print providers as a way of helping ensure they get the colors they expect.

G7 is an interesting process I’ve written about before. Idealliance recognized PRISMAsync as the first G7 embedded complete closed loop system for electrophotography nearly five years ago. It is being used in conjunction with Canon’s PRISMAsync Color Print Server to help customers monitor and verify their conformance to G7 standards for production printing.

The history and stats are interesting, but I still wanted practical insights, so a little Q&A was in order. I talked with some people at Canon and was allowed to sit in on a call between a Canon color guru and Canon customer Print-Tech in Ann Arbor, Michigan, a print provider that does both offset and digital print production. Print-Tech uses G7 to ensure output is accurate, repeatable and consistent across digital and offset platforms. The fellow on the Print-Tech end was Brad Steven, IT and Digital Production Manager with industry experience going back to 1994.

Canon: One of the things we always hear is that repeatability is one of the most important factors when using a digital press. How does it play into the jobs done at Print-Tech?

Brad Steven:
Repeatability for us is important for three reasons. First is if we’re running a proof today but not running the job for two or three days, I want the proof to look like the job we’re going to put out. The printed version must look exactly the same when we run the full job. Second, if we are printing a job today, and it is going to be reordered in three months and the two versions may be on a shelf next to each other they have to look the same. And third, we’re also a traditional offset printer, so we want digital and offset jobs to look as much alike as possible so we can move jobs back and forth between digital and offset presses. This gives us flexibility in terms of print volumes, press time available, customer needs and other factors.

Canon: That sounds like a lot of things that have to line up. How do you make that happen?

Brad Steven: The best method for us today is G7. We’ve used GRACoL 7 but it is not as tight on its tolerances. What we like about G7 is that we can do everything ourselves without an outside expert needing to be involved for every job. With G7 we can perform the needed tests on a day-to-day basis with just an annual visit from a G7 expert to validate our processes.

Canon: That sounds like it helps you get to accurate color faster and makes things a lot more efficient. But tell me this. When a customer asks, ‘How accurate is your color?’ what do you say?

Brad Steven: That would depend on who is asking the question (laughed).

Canon: So true!

Brad Steven: A key piece of the answer to that question is what the customer is expecting for accurate color. We make sure they understand that what they may have seen on screen is not necessarily what the file really is, in terms of color. We talk about repeatability, and that if a customer gives us a file we want to ensure we will be able to reproduce the file correctly, but that it may not be what they see on a monitor or maybe have seen in a printed version done somewhere else.

Canon: That’s a familiar problem. So how do you get the best accuracy?

Brad Steven: By using G7. The proofs from our offset presses are checked every day, the digital presses are calibrated twice a day. Using PRISMAsync on the Canon imagePRESS C10000 we do an internal G7 validation so that when we produce a proof it is within spec and then when we run the job we look again and to make sure it is within our tolerances.

Canon: OK. That’s part of the story. But I know G7 has some different conformance levels. Do you have levels that you target?

Brad Steven: We go for color space and are G7-certified for color space on all our devices.

Canon: I think there are three conformance levels for print providers: gray, targeted and color space. Color space is the most demanding, right?

Brad Steven: It is, and we have made the effort to get there because we need to make sure the whole color space is correct. It is not just a matter of getting gray balance right. By doing the whole color space we can assure a customer that we can reproduce a color repeatedly.

Canon: That means not just the neutrals and the contrast but all of the colors?

Brad Steven: Right. Because we’re producing color. We need to know that all of the color will look right. That way when they give us a shade of red they know we know we will be able to reproduce that red every time they need it.

Canon: OK. But since we don’t live in perfect word, how do you respond when a customer tells you the color is not what they wanted?

Brad Steven: There’s two pieces here. First we look to make sure the color, or the whole printed piece, passed our G7 validation. If it did we explain the process to the customer and acknowledge that they are not accepting the output. We drill into this by asking what their expectation is based on. Is it what they saw on a screen, is it a previously printed piece, or is it just too…”blue”… for the customer. Next, we work collaboratively with the customer to find out where they want to go. It may be that we—or the customer—need to make adjustments to the file.

Canon: Do you think a visual evaluation of color is trustworthy enough to run your business on or is that more of a general measure?

Brad Steven: That is more of a general approach for us. You can see overall if it is in the right color gamut but that is still really just a qualitative measure. Going deeper it becomes more quantitative. We really need to know that a specific color is being produced with a set tolerance. If we don’t have that we’re relying on how everyone sees color. Because everyone sees color a little bit differently that can be more accurate or less accurate.

Canon: You’re saying that the only way to confidently measure color is by the numbers. Talk about that for a minute.

Brad Steven: Without the numbers we can’t have a conversation with a customer on where they want to be. For example, a customer may say a proof looks too blue when they are sitting at their desk under a fluorescent light. But when we see it under a D 50 (daylight) lamp in a viewing booth it looks correct. It shows that where you are viewing the content is just as important as producing the content.

Canon: Job files come into your shop in different color spaces: RGB, CMYK, Pantone names, and so on. This can be a big variable so how do you handle it?

Brad Steven: We see work coming in in all those spaces and in a mixture of all of them. The first step on all jobs is pre-flighting to see what spaces are being used, plus some other quality control elements, like image resolution. Then we convert all the colors to CMYK using a GRACoL® and G7 conversion process so the colors are meeting those standards. Then when we send the file down to the digital press there is no color space conversion required by the press beyond producing the CMYK values. So as long as our press is calibrated and running under G7 specs the job is always going to print the same way. We call the whole process pre-production—everything that occurs before the job goes on press.

Canon: You said before we started this interview that you run the Canon imagePRESS like a press, and this sounds like one of the ways you achieve that. Are these linked ideas?

Brad Steven: They are linked. On the offset side all the files come to the press operator so all he or she has to think about is putting the plates on the press, running the job and comparing it to the proof. We do the same with the Canon imagePRESS. A job goes through pre-production and when it reaches the press the press operator just has to run the job and compare it to the proof. This keeps the technical work in the hands of people who do that all day and lets the press operators focus on maintaining color, doing calibration if necessary and making sure there are no issues with the file, but they are not adjusting color.

The other benefit is that it’s really easy to take a job that we had run as a long run on an offset press and move it to the imagePRESS C10000 for a short run. Because they are both in the same color space we know the output from both presses will be likely to match.

Canon: That sounds really smart. So one more thing. Could you share what it has been like training digital press operators to use a new front-end like PRISMAsync?

Brad Steven: It’s really a process of operators learning all the basic tasks and showing them the newer and more advanced functionality. When we installed our Canon imagePRESS C10000VP, we began using PRISMAsync because of its functionality and G7 capabilities. But we quickly found that having people move from a system they had been using for 10 years to something entirely new is a challenge. So we spent time every day walking through how each task was accomplished. As they got used to the new system and realized that it was faster and easier to use, they reached the point where they didn’t want to go back to the old system. Now they comment on how much more efficient PRISMAsync is for managing production.

This was a fascinating conversation because it let me hear the G7 story from the perspective of a shop using it for both offset and digital printing. What it told me is that G7 grayscale compliance is an excellent way of helping ensure colors will maintain a shared neutral appearance between different presses. G7 colorspace compliance is a great way of ensuring your printing system can consistently reproduce an entire color space like GRACol within tight tolerances. G7 seems to be a good approach to a continual problem for offset and digital print providers.
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Bill Ward

Canon has been improving their color approaches over time. We were using Colorlynx with our digital presses and now we run G7.
G7 is the best process we've used thus far over a pretty broad range of colors...but will it drift over time?


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