Large-format Scanners25/01/2006 |
| This product survey focuses on high-resolution, large-format scanners with colour depth of up to 48 bits for transferring large-format hardcopy images and maps to digital format. The resulting raster data is meant for use in a GIS environment, either as backdrop or for conversion to vector format, for example by head-up digitisation. Accordingly, the survey does not include photogrammetric scanners. |
| Mathias Lemmens, editor and Jacques Sipkes, contributing editor GIM International |
|
Most scanners are of sheet-feed-through type. This enables scanning of really large format hardcopies, the length of which may be virtually endless whilst the width may vary from 63.5mm (25 inches) to 137.2mm (54 inches), depending on scanner type. The depth of each of the colour bands may vary between 8 and 16 bits; more bits do not, however, necessarily mean higher quality, because the required number of bits depends largely on noise level and dynamic range of the original document. All the listed scanners are capable of basic input manipulation operations including pre-scanning, cropping, scaling, zooming, angle correction and conversion from colour to B/W. Nearly all digital image processing software delivered with the scanners is capable of standard image processing operations including enhancement, sharpening, softening, contrast manipulation and (adaptive) thresholding.
|
|
| Archive |
| Archive > August 2005, Volume 19, Issue 8 > Large-format Scanners |
