Wednesday, August 26, 2009

Ink Key Presets: The key to faster makereadies

First of all, I want to thank all of you who have responded to the new way were are trying to communicate. Second, I’ll be going over some terms and concepts, if you feel that you already know this, go ahead and skip to the next section.

With press runs getting shorter and shorter and the cost of paper going up, up up, this time I’d like to talk about CIP3, CIP4, JDF, and ink key presets. First, let’s define what CIP3 is: CIP3 is a print production format specified by the Fraunhofer Institute for Computer Graphics. They worked in close collaboration with a group of well-known software and equipment manufacturers. This group was called "International
Cooperation for Integration of Prepress, Press, and Postpress" (abbreviated as CIP3).


It was developed as a way to bring the printing and post printing processes closer to prepress. The idea behind this was that the information generated in prepress should flow downstream to the pressroom for further processing. This would avoid having to re-acquire data in the pressroom that was already available in prepress.


The challenge was getting many equipment and software manufacturers to come up with a common way of communicating with each other. The end result of this endeavor was the CIP3 Print Production Format or PPF. The PPF is a file that contains all the necessary data for printing and further processing of a job, except for the high resolution data for printing. Things like plate size, paper size, colors being used, register mark info, previews, folding, etc., can be included in a PPF file.


CIP4 is the International Cooperation for the Integration of Processes in Prepress, Press and Postpress Organization. The folks at CIP4 are responsible for JDF. JDF is an industry standard that goes one step further than CIP3. While CIP3 covers what happens to a job beyond prepress, the idea behind JDF is to simplify data sharing among the different applications and systems in and around the graphic arts industry. Like other standards, JDF is based on XML. This allows easy integration with Internet solutions. To find out more about JDF, visit www.cip4.com


Data in JDF can be used in prepress or the pressroom. For example, data gathered during the estimating phase of a job, such as the type of paper the job should be printed on, will be used in prepress to determine what kind of ICC profiles should be used. And then, in the pressroom, to determine which press the job should be printed on.


Enough with the acronyms, let’s talk about ink key presets.


Imagine this

The printing area of a press is divided into zones. Each zone is fed ink by an ink duct. And the amount of ink that goes into the duct is controlled by an ink key.

The amount of ink to be delivered depends on the amount of data on the zone. In other words, if there is no data in the zone, the ink key is closed. If there is a solid color that fills the zone, then the key opens to meet the ink demand.


How much ink is needed?

That is where color bars and ink density come into play. As the press prints, the press operator adjusts the ink key until a certain ink density is achieved by measuring each color on a color bar. Ink density is nothing more than how thick is the ink is on paper.

The number of ink ducts on a press depends on the press width. Depending on the manufacturer, the ink keys will be more or less numerous. Most of them are a little over an inch wide. So the wider the press, the more ink ducts that need to be adjusted. The more color units a press has, the longer it takes to get the colors dialed in at the right densities.


And finally, on to our stuff

Compose has a product called Express InkScript that would sit on the pre-press department, or the front side of this equation. It takes PS, PDF or 1 bit tiff files (digital plates) and converts them into ink duct data. This ink duct data can be automatically saved as a PPF file (see paragraph 4 above if you need a refresher course). This PPF file is sent to the press room. Or, InkScript can generate a PDF file with a color preview of the job, under a grid representing the ink ducts. And an ink duct histogram per each color used in the job. This makes it very easy for press operators to adjust the initial ink key values on presses that do not have ink consoles.


If the press has an ink console, that PPF file arrives at the pressroom and is processed by Ink Zone, the back side Compose app in this equation. Ink Zone displays a list of jobs that are available for immediate printing. Once the press operator selects one, it’s sent to the press and the ink keys are configured with the accurate values.


Ink Zone learns from the press. Once a job has finished printing, the operator has the option to archive it to print it again at a later day. Or save the difference of what he originally got from InkScript and what he adjusted on press. The more the operator uses the system, the closer to being perfect that the ink keys are at startup. Customers of ours that are using this are reporting a 90% to 95% proximity to their goal at press startup.



A Closed Loop System can be installed with Ink Zone by using a color bar with the width of the job and an automatic reader, such as X-rite’s Intellitrax. With the automatic density readings, Ink Zone can tell the press which ink keys to move up, and which keys to move down. This option further reduces the make ready time.

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