Targets
Calibrating all devices involved in the process chain (original, scanner/digital camera, monitor/printer) is required for an authentic color reproduction, because their actual color spaces differ device-specifically from the reference color spaces.
An IT8 calibration is done with what are called IT8 targets, which are defined by the IT8 standards.
- Example
Special targets, implementing the IT8.7/1 (transparent target) or IT8.7/2 (reflective target) standards, are needed for calibrating scanners. These targets consists of 24 grey fields and 264 color fields in 22 columns:
- Column 01 to 12: HCL color model, which differ in Hue, Chroma, and Lightness
- Column 13 to 16: CMYK-Colors Cyan, Magenta, Yellow, and Key (black) in different steps of brightness
- Column 17 to 19: RGB-Colors Red, Green, and Blue in different steps of brightness
- Column 20 to 22: undefined, producers' choice
After scanning such a target, an ICC profile gets calculated on the basis of reference values. This profile is used for all subsequent scans and assures color fidelity.
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