Closing the Loop on Color Management in Offset Printing Environments

Closed loop color management is becoming an important trend in offset printing environments, and for good reason. Press runs continue to get shorter which means more makereadies and reduced profits for printers. For those of you that have already invested in an automated color bar scanner to shorten your makereadies, you are half way there. So now let’s talk about “closing the loop” on color, examine the benefits, and see just why this trend is on the rise.

To introduce the benefits of closed loop color control, let’s take a minute to define the system components and see how each piece contributes to the ultimate goal of saving you money by decreasing your makeready costs.

A good closed loop system consists of the following components:

  • Ink “Pre-setting” Software — This software takes information from your RIP output, calculates the ink coverage for each color, and converts it to ink key and ink sweep settings for each print unit. The reason “pre-setting” is in quotes is that this software does not actually set the ink keys on press, instead it converts the ripped data to the format that is needed to ultimately set the keys. Typically, printers will only need one license of ink “pre-setting” software per location.
  • Automated Scanning Spectrophotometer — The automatic scanning spectrophotometer integrates into the closed loop system seamlessly. You simply place a printed sheet on the console, align with the color bar, press the measure button, and the scanner automatically moves across the sheet measuring each color patch in each ink key.
  • Computer and Press Console Interface — The system requires a combination of a relatively basic computer and a very sophisticated piece of hardware that lets the computer interface or “talk” to the console. Some press manufacturers have a way to talk to the console, through a protocol called Direct Press Interface while others need a hardware box that emulates a memory card, disk drive, or network. The good news is there is a way to interface with almost every press console out there.
  • Software Management System — This is where the heavy lifting happens and while this software will seem like a lot, it can be user friendly and easy to use, even for non-technical users. The software needs to do many things each of which is important to closing the loop. Initially upon installation, it needs to be configured for your shop and specific press. Information including color standards, standard CMYK densities, print tolerances, color bar data, how many ink zones, how many print units, and does the press perfect will all need to be entered.

During operation, the software takes the ink pre-setting information and sends it to the console. It needs to manage the automated scanner, display the data in an easy to see and understand format and send the corrections to the press console. That in itself is not really closed loop. Sure, you are adjusting the press based on color measurements, making automated adjustments to ink keys and repeating, but it is not a fully closed loop. There is one other loop to close.

This one is the most important loop and gets you the biggest bang for your buck. The software needs to collect all of that valuable measurement data for all of your colors on that specific press and it needs to be able to periodically adjust the incoming ink pre-setting data. Why is that important? Well it boils down to this, each and every maker of ink pre-setting software can only get so close to the perfect ink key and sweep settings for your press. That is due to differences between presses, plates, processes and more. Closing this final loop gets you from approximately 70% of the way to optimum ink key settings, to 95% or better.

So now that we know about the system components, let’s turn toward the savings you’ll reap when closing the loop. The most glaring is in reducing makeready costs. As you can imagine, if you have no ink pre-setting and you implement a fully closed loop system you can go from many hundreds or even thousands (I’ve seen it) of sheets in makeready, down to just a hundred or so. Even if you have ink pre-setting and you close that loop you can go from a few hundred to even less. That may not sound like a lot, but it can and does add up to thousands of dollars or more over time.

Now let’s talk about G7. You all know the print shop, you may even be the print shop that pays a lot of money for a consultant to come in and fingerprint your press, set up curves and establish standard densities, but then the instant they are gone, it is back to the operator running the press the way they want to. Using a closed loop system ensures that the targets are there and helps the operator understand that by running to these aim points they actually get better color more of the time, and in less time.

Then, since your operator is not having to manually measure the colors on the bar, and does not have to adjust each ink key for each color manually like they are playing the piano, they have time to ensure that your print quality is good. They will also have time to ensure registration is tight, and to spot hickeys and other defects that creep into the process, with time to correct them.

If you are thinking that you would love to close the loop but your shop is too small or you don’t have the budget, continue reading! There are many return on investment calculators out there that will tell you just how fast you will recoup the costs of the system. Many times it can be within 6 months or less and after that you are saving money on every job thereafter. Yes, color is important and good quality print is important, but to run a successful and more profitable company you need to save more money on each and every job, and that’s the power of closing the loop on color!