Contex IQ 2400 Series, Technical Service Manual

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Service Guide IQ / IQ Quattro
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Black Level
The Black Level is a setting in scan programs used to change dark graytone colors to true black. For example, if one is copying a brochure with a mixture of text and
pictures, the text will often be digitized to a color that we may see as black but really is a dark graytone. When the printer digests this graytone data, it will print the
original’s text with a halftone pattern, meaning scattered dots instead of solid black. By increasing the Black Level value, one can get the text to be copied in real
black and it will therefore appear clearer.
Black Point Adjustment
An adjustment made that will determine the amount of shadow detail in an image. It is considered proper to set the black point so that the darkest part of an image
will only just have zero detail.
Blueprint
A process of photographic printing used mainly for copying architectural and mechanical drawings; produces blue lines on a white/bluish background.
Blur
The averaging of pixel elements.
Brightness Adjustment
An adjustment on a scanner that allows the user to compensate for a light or dark original.
Calibration
Adjusting a device so that it performs in accordance with an established standard. Scanner calibration is minimizing color deviation between scanned ANSI IT8
reference color patches and the known color reference values. Generally, Calibration is the process of setting a device to known color conditions - stabilizing the
device to a known and quantifiable state. Calibration is commonly done with devices that change color frequently, such as monitors (phosphors lose brightness over
time), scanners (light changes) and printers (proofers and other digital printing devices can change output when colorant or paper stock is changed).
CALS
Computer-aided Acquisition and Logistics Support (CALS) standard, a U.S. Defense Department and industry initiative that addresses the design, manufacture, and
support issues of generation, access, management, and use of technical data in digital form.
CCD
Charge Coupled Device, CCD is the image sensor in the scanner that converts light to voltages. These voltages are converted by the scanner into the image.
CCITT Group3
Standard run-length compression format used with FAX transmission. It utilizes modified Huffman coding to further compress the runlength numbers. Most scanner
file formats are dialects of this format.
CCITT Group4
Two-dimensional compression format, giving very compact image files. Standardized by CALS (MIL 28002) and ISO-ODA for Drawing Archival and Interchange.
CIE LAB
A device-independent color space specified by CIE, used in modern color management software to facilitate conversion of data from a scanner to a display, or from
a display to an output device.