User's Manual

23 Troubleshooting scan-quality issues
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Random vertical lines
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Wrinkles or folds
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Line discontinuities
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Grain in area fills when scanning plain paper
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Small color differences between adjacent CIS modules
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Vertical light lines at the intersection between CIS modules
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Variable line thickness or missing lines
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Inaccurately reproduced colors
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Color fringing
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Clipping in dark or light areas
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Flare in the image when scanning glossy originals
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Vertical red and green bands over white or black background
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The stop-start effect
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Vibration
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Horizontal periodical banding
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Defocus, blurring and fading colors
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Incorrect paper advance, skew during scanning, or horizontal wrinkles
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Vertical black band 20 cm wide
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The scanner damages some originals
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Completely wrong colors
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Vertical distortion
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Object replication (ghosting)
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Clipping or incorrect scale factor when down-scaling in copies and prints
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Incorrect edge detection, mostly when scanning tracing paper
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A copied or scanned image is very skewed
In this chapter the most common defects and failure modes are shown, sorted by relevance and frequency of
appearance. A defect is a common image artifact that usually appears when using any CIS scanner. These are
ENWW 201