Brief summary from some of the TC 130 WGs meeting in the Spring

Brief summary from some of the TC 130 WGs meeting in the Spring

WG 1 Terminology; The work on ISO 5776 Symbols for text proof correction has been completed, and the standard is out for its final ballot before being published. The revised version includes mark-up for the Korean Language. Work on terms and definitions is continuing and consideration is being given to developing a standard on the design and layout of documents.

WG 2 Prepress data exchange; ISO 28178 Exchange format for colour and process control data using XML or ASCII text is under revision to include terms used for ECG (Expanded Colour Gamut). The standard ISO 12642-3 Input data for characterization of 4-colour process printing — Part 3: Extended data set has been extended with the new test form IT.8/7-5.

WG 3 Process control and related metrology; a new project has been started on ISO/AWI 24585 Multispectral measurement and colorimetric computation for graphic arts and industrial applications. This is to complement the standard ISO 13655 Graphic technology — Spectral measurement and colorimetric computation for graphic arts images, adding some restrictions on sensors regarding optical bandwidth,  having a modified definition on geometry, adding D65 as a possible light source and adding a framework for the calculation of a quality index. The standard may be split into two parts; part 1 covering metrics and part 2 covering tolerances.

The work on a major update of ISO 12647-2 Process control for the production of half-tone colour separations, proof and production prints — Part 2: Offset lithographic processes continues. A central part of this update is to allow calibration of a press according to either the TVI (Tone Value Increase) method or the Near-neutral method (also called NNC, Near Neutral Calibration). Since what calibration method is used will determine which ICC-profile to use in the prepress work, it will be important that the print service provider clearly states which calibration method they use and communicate this to print buyers and the designers. TC 130 WG 3 is investigating whether a common characterization data set can be created that represents both calibration methods in an acceptable way, but this work has not been concluded. An updated version of ISO 12647-2 is not expected to be published until, at the earliest, 2022.

More parts of the ISO/TS 18621 family – Image quality evaluation methods for printed matter – are being prepared or revised. Among them are Part 11 Colour gamut analysis, Part 21 Mottling (M-Score) and Part 22 Graininess (Z-Score). The 18621 series of test methods provides very useful test methods for anyone who needs to assess the printing quality of an analogue or digital printing system.