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Following is a glossary of color terminology used in supporting literature for the Imation Rainbow™ Color Proofing System. Use this as a quick reference guide.

CheckCal
Function of Rainbow™ Color Locking Software. Used to quickly check and monitor the color accuracy of a proof. The Rainbow™ Controller Software allows users to print the CheckCal control scale on a proof. After reading the CheckCal scale using a spectrophotometer, the software indicates when it is time to recalibrate using SuperCal.
Other definitions: Color Locking Software, SuperCal

Color Calibration
Feature of Rainbow™ Controller Software. The Rainbow™ proofing system allows for moderate color adjustment of the Rainbow™ proofer through the Ink Ribbon Calibration and Color Target Adjustment tools.
Other definitions: Color Locking Software, Color Target Adjustment, Ink Ribbon Calibration, Visual Color Calibrator

Color Libraries
Feature of Rainbow™ Controller Software. For users who wish to proof/print specific colors, Rainbow™ software includes three color libraries: PANTONE™, 3M™ Matchprint™, and User Colors libraries. Users also can create their own customized libraries. Colors included in these custom libraries will be output according to their L*a*b* color space measurements. Users can add, delete, duplicate, or edit colors from unprotected color libraries. (The PANTONE™ and 3M™ Matchprint™ libraries are protected.)
Other definitions: L*a*b* Color Space

Color Locking Software
Used in conjunction with Rainbow™ software's Ink Ribbon Calibration procedure to maintain color consistency between Rainbow™ ink ribbon lots and from proofer to proofer. Color locking software ensures that color remains accurate and consistent with supported color targets. This software uses numerical measurements input directly into the software via spectrophotometer readings, eliminating subjectivity in color calibration.
Other definitions: Color Calibration, Ink Ribbon Calibration, Reference,
Make Reference, L*a*b* Color Space

Color Target
Feature of Rainbow™ Controller Software. User-selectable from the General Preferences dialog box. The Rainbow™ proofing system will simulate the color and density of specific printing conditions according to the color target selected. The Rainbow™ color targets closely approximate the 3M Matchprint™ color proofing system which simulates printing conditions such as Commercial, Publication, etc.

Color Target Adjustment
Feature of Rainbow™ Controller Software. The Rainbow™ system allows for slight modification of standard color targets via adjustment of tonal curves which effectively changes dot gain. User-selectable from the File Menu of the Rainbow™ controller software.
Other definitions: Color Calibration

Ink Ribbon Calibration
Function of Rainbow™ controller software. Color calibration procedure used to adjust the Rainbow™ system to compensate for variations between ink ribbon lots as well as to compensate for different printing conditions, such as temperature, humidity, and storage, and handling of supplies. Used in conjunction with the Imation Visual Color Calibrator or Rainbow™ Color Locking Software.
Other definitions: Color Calibration, Color Locking Software, Visual Color Calibrator

L*a*b* Color Space
Scheme for representing color as numerical values. L*a*b* refers to a three-dimensional color space model: L* indicates on a scale of 0 to 100 the appearance of a color ranging from black to white; a* indicates on a scale of -120 to +120 the appearance of a color ranging from green to red; b* indicates on a scale of -120 to +120 the appearance of a color ranging from blue to yellow. Every color has a specific L*a*b* value. A spectrophotometer is used to measure colors to obtain their L*a*b* values. Rainbow™ system users can add specific colors to unprotected color libraries by entering the L*a*b* values of that color into the Separation Editor dialog box of the Rainbow™ controller software. (See "Separation Management" in the Rainbow™ Color Proofing System User's Guide for further information.

Make Reference
Function of Color Locking Software. Allows the user to create customized references (see Reference below) to achieve a different look for their proofs from the supplied Matchprint™ references; for example, the user can create a reference with a gray balance or dot gain different from the supplied Matchprint™ reference. Custom references can be transmitted to remote sites to ensure site-to-site calibration.
Other definitions: Color Locking Software, Reference Files

Reference
Function of Color Locking Software. Preference set in Color Locking Software before performing the SuperCal calibration procedure. The user selects a reference for the type of printing conditions they wish to emulate and to which SuperCal will calibrate. Supplied reference files in Color Locking Software simulate Matchprint™ conditions such as Commercial, Newsprint, Publication, Euro Color, etc. The user can also create a customized reference (using "Make Reference") to match specific calibrations.
Other definitions: Color Calibration, Color Locking Software, Make Reference, SuperCal, CheckCal

SuperCal
Function of Color Locking Software. Calibration procedure used to calibrate the Rainbow™ system to a chosen reference (see Reference above). It should be used when first setting up the Rainbow™ system, after changing the ink ribbon, and whenever CheckCal indicates that a SuperCal is called for.
Other definitions: Color Calibration, Color Locking Software, CheckCal, Reference

Visual Color Calibrator (VCC)
Used in conjunction with Rainbow™ software to maintain color consistency between Rainbow™ ink ribbon lots and from proofer to proofer. The VCC is a visual guide to help users set a proper gray balance. ( The other tool available for maintaining accurate and consistent color is Imation Color Locking Software [see above]. Instead of the user visually setting the proper gray balance, color locking software uses numerical data obtained by measuring color elements with a spectrophotometer, eliminating subjectivity.)
Other definitions: Color Calibration, Ink Ribbon Calibration