ISO 12642-3 is the third part of an international standard that deals with information about graphic technology.
ISO 12642-3 defines a data set of ink value combinations that can be used to characterize four-color process printing. While it is primarily aimed at process color printing with CMYK inks, it can also be used with any combination of three chromatic inks and dark ink.
ISO 12642-3 specifies and explains the background, terms, and definitions as well as the technical requirements such as tone value precision, data set definition, layouts for printing, compatibility with data based on the ISO 12642‑2 target, related to the characterization of 4-color process printing.
Note 1: ISO 12642-3 is not optimized for any printing process or application area but is robust enough for all general applications.
Note 2: ISO 12642-3 can be used as an alternative to the ISO 12642‑2 data set where more neutral scale data are desired, but It is not a replacement for ISO 12642‑2.
ISO 12642-‑3 on Characterization of 4-color process printing is useful for:
The characterization target ink value combinations defined earlier, have proven very effective for use in characterizing various printing processes. But there was a need for a visual layout and manual reading of the target.
ISO 12642-3 leads and guides you to fulfill the need to have some ink value combinations repeated in both single-color scales and in various overprint combinations. It implements new ink value combinations, as the increased use of neutral scale calibration proves these patches would be more useful as additional black only patches and near-neutrals.
ISO 12642-3 uses some of the duplicate patches to verify the consistency of ink value combinations. It uses multiple targets, averaged measurements, and printing of targets processes that can be used for the capture of the desired data.