Image Access WideTEK CIS scanner Contex large format scanners

EXPLANATION:

Large format scanner accuracy and calibration

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Colour accuracy

All devices in a system (e.g. scanners, printers, screens) handle colour in a different way. They may use different colour spaces (for example RGB, sRGB or CMYK) or support wider or narrower ranges of colours.

In order to match colours across a system so that the colours you print are the same as the colours on the original scanned document, you need to create a description of the way each device handles colours. This description is called a "device profile". Device profiles are also known as "ICC profiles" (Mac) and "ICM profiles" (Windows). ICC and ICM profiles are the same but the profile files have different extensions.

IT8 Target
IT8 target

To create a device profile for a scanner a chart of known colours called an IT8 target is scanned. The scanned colours are compared to the known colours on the target and the relationship between the scanned colours and the known colours is calculated.

The scanner's device profile can then be used in conjunction with a printer's device profile to match colours in a scan to print system. Alternatively, the scanner's device profile can be embedded in a scanned file so that colours can be matched in any program that supports colour matching, such as Photoshop.

Some scanners are automatically supplied with an IT8 target and software that allows a device profile to be created (Contex). With other scanners, this is an optional extra - to profile a Colortrac scanner you will need Colortrac's optional CopySmart software. Image Access scanners are supplied with a ready-made device profile. At present this profile cannot be fine-tuned, however in spring 2008 Image Access will be launching an online calibration service that will allow users to create new device profiles as often as necessary. At present, Graphtec scanners have no software available for creating a device profile.

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