IT8

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IT8 refers to a summary of several ANSI standards for color control , which were defined by the IT8 Committee in 1993, but have been administered by the Committee for Graphics Arts Technologies Standards CGATS since 1994. Scanners, digital cameras, monitors and printers are now calibrated according to these standards in order to guarantee color accuracy.

List of standards

The following list contains the IT8 standards:

IT8.6

  • 2002 - Graphic technology - Prepress digital data exchange - Diecutting data (DDES3) -

This standard specifies a format for the exchange of numerical control data between electronic prepress systems and die-making systems.

IT8.7 / 1

  • 1993 (R2003) - Graphic technology - Color transmission target for input scanner calibration -

This standard defines the layout and colorimetric values ​​of the test targets with which see-through color scanners can be calibrated.

IT8.7 / 2

  • 1993 (R2003) - Graphic technology - Color reflection target for input scanner calibration -

This standard defines the layout and colorimetric values ​​of the test targets with which overhead color scanners can be calibrated.

IT8.7 / 3

  • 1993 (R2003) Graphic technology - Input data for characterization of 4-color process printing -

This standard specifies input data, a measurement procedure and an output data format in order to be able to characterize 4-color printing processes.

Application - IT8 target

IT8.7 / 1 target

A binding color reproduction in the process chain (template - scanner / digital camera - screen - printer) requires calibration of all devices involved, since their actual color spaces differ from the reference color spaces depending on the device. An IT8 calibration is carried out with so-called IT8 targets, the shape of which is clearly defined in the IT8 standards.

Example: For the scanner calibration, templates are to be used that meet the standards IT8.7 / 1 (transparent targets) or IT8.7 / 2 (reflective targets). According to these standards, an IT8 target contains 24 gray fields and 264 color fields in 22 columns:

  • Column 01 to 12: Colors of the HCL model , which differ in hue (hue), color intensity (chroma) and brightness (lightness).
  • Columns 13 to 16: CMYK colors cyan (blue-green), magenta (purple), yellow (yellow) and key (black) in different levels of brightness.
  • Columns 17 to 19: RGB colors red (red), green (green) and blue (blue) in different brightness levels.
  • Columns 20 to 22: not defined, the choice of color is up to the manufacturer.

Such a target is now read in with the scanner and a so-called ICC profile is calculated based on reference values. This profile is taken into account in all subsequent scan processes and ensures a true-color scan result.

See also

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