Regularly Spaced Bands Appear on LS-8000 Scans The LS-8000 generates bands which could be characterized as periodic strips running at right angles to the direction of the scan. Ordinarily these bands are not visible as in this raw scan of a monochromatic source: The bands become visible on the monitor only after a substantial increase in contrast: Banding is more likely to be noticed on scans of negatives because they undergo substantial contrast enhancement as the black-white points are applied. In addition, I would note, that the banding phenomenon is more likely to be noticed on prints made from these scans, especially in highly saturated areas such as blue skies. If most of the material that you scan is transparencies, it's unlikely that banding will be noticed. This is probably why the problem wasn't evident to me, even after having an LS-8000 for several months. Cause: Some experts have attributed the problem to miscalibration of the CCD sensor strips, seemingly a software problem, yet the LS-9000 does not have the banding problem. Remedy: Scan with the SuperFine option. Comment: Banding is otherwise most frequently caused by dirt on the CCD sensors, and will appear along the scan motion. In this case, if it's a single band, the appearance is singular or, if more than one, they are spaced irregularly. |
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