Closed-loop colour control is considered by many press managers and operators as essential for efficient production.

Let's try to demystify the sometimes mixed, but complimentary roles of closed-loop colour control with the quality assurance, measurement and reporting features of pressSIGN and see why they make a great working combination.

The role of a closed-loop system is to adjust the ink keys in order to achieve a Target density across the sheet.

Unlike CIP3/4 data, adjustments are calculated from measured sheets during the press run. Changes are transmitted to the press by the operator following the scan of the full sheet colour bar.

The most obvious benefits are savings are in make ready time,  more efficient ink key adjustments and improved colour stability during the print run.

Saving money on waste and press time is the reason d'etre.

A press console and scanner used for closed-loop colour control

pressSIGN Pro links with all major closed-loop systems, and can be set up to automatically gather the colour measurement data and set up Jobs for quality assurance and technical reporting.

This is called AutoMode.

With AutoMode pressSIGN automatically gathers data from the closed-loop system, meaning that no operator interaction is required. AutoMode can even automatically create the Job name whilst pressSIGN's clever AutoMode Aliases deal with common settings not included in the closed-loop system data.

 

All relevant data is compliled in the pressSIGN database for all of your pressSIGN tools - Reporting, quality assurance, curve monitoring and output.

However closed-loop is not a golden bullet!

A closed-loop system doesn’t do everything. Other controls need to be in place before print utopia is reached.

This is where pressSIGN comes in to help...

  • Curves are needed to control the tint values
  • Curves are needed to control gray balance
  • Know how well are your inks trapping for overprints
  • extend that to Spot colours !
  • Printing Multi-color e.g. CMYKOGV etc. hows that going ?
  • What about printing to custom standards and reporting ??

pressSIGN's Colour Bar view showing adjustments for each colour across the (offset litho) press.

Ideally these would 'flatline' using a perfect closed-loop colour control.

Most closed-loop systems have their own version of this screen/view.

A typical closed-loop view, press console and scanner

pressSIGN can monitor a Hot folder for incoming files from any connected scanning system, plus it can even export adjustment data files directly to a connected closed-loop controller, thereby acting as the colour calculation software.

 

The drop down list (left) shows the options for output of industry-standard closed-loop file types.

pressSIGN accepts measurement data, with the right export modules or licenses from:

  • Heidelberg Image Control 1 & NG
  • Heidelberg Axis control I & II
  • Heidelberg Inpress control
  • Komori PDC-S II & PDC-SX
  • KBA Densitronic-S & Lithec head
  • Manroland Color Pilot GM & CP Smart

pressSIGN is an ideal partner in combination with the following third-party closedloop systems:

  • Rutherford Graphic Products systems
  • Techkon Press Link/PrintFlow
  • Digital information InkZone

The combination of a closed-loop system working in conjunction with pressSIGN is empowering. The closed loop system does not store measurement data whilst pressSIGN stores measurements and provides statistical data for technical and quality managers.

What are the alternatives without a full closed-loop ? If you don't have a closed-loop colour system you can still utilise pressSIGN's measurement data to control the colour on your press. It's what pressSIGN was made for. Connecting one of the many spectrophotometer scanning devices from either X-rite or Techkon, in seconds the press operator can view and make manual adjustments to control the colour (ink keys) manually. You can even use handheld scanning spectrophotometers including the i1 Pro, X-rite eXact, SpectroDens and more.

Call us for practical advice on how pressSIGN can improve your system