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Proofing RGB Files Directly
The increased color capability of Imation™ Rainbow™ Color Proofing System software v4.0 allows you to proof RGB (Red, Green, Blue) files directly to the Rainbow™ system so you can predict how an RGB image will be reproduced in the printing process, before traveling through that process. The Rainbow™ software v4.0 proofs RGB files by internally converting them to CMYK (cyan, magenta, yellow, black); and the resulting Rainbow™ proof will show you how an RGB image will look when printed in the CMYK mode.

How Can this Help?

For Designers...
In many instances an RGB file may turn out radically different when converted to CMYK. (This occurs more often with a digital photographic application.) For designers who prefer to perform color corrections in RGB files, the capability of proofing an RGB file directly to the Rainbow™ system will enable them to see how the image will look after the CMYK conversion while still allowing them to make color corrections in the RGB file.

For Graphic Arts Vendors...
For customers who only wish to supply vendors with RGB files, the vendor can directly proof the RGB file and show the customer how their job will look when printed as a CMYK image.

Rainbow™ System RGB to CMYK Conversion Table
The Rainbow™ software default RGB to CMYK conversion table is set up to approximate the RGB to CMYK conversion table used in Adobe™ Photoshop™. If not using Photoshop's default conversion table, the user can change the Rainbow™ system default table to better approximate the RGB to CMYK conversion system they use (for example, to simulate conversion calculations used by a high end system such as Scitex.)

Customizing the Rainbow™ System RGB to CMYK Conversion Table
Imation supplies an RGB to CMYK TIFF image that can be used to change conversion calculations to best simulate the user's system. This RGB TIFF image is read by the user's system, converted to CMYK, then written back as a conversion table for the Rainbow™ system. This table must be saved with the same name as the Rainbow™ system's default table. During RGB to CMYK conversion, the Rainbow™ software will read this table and use it exactly as if the conversion were being done with the user's system.