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c. The Kelsh Plotter, Model K-5, is capable of handling two, three, or
four projectors. Use of virtually distortion-free photography has resulted in
maximum rigidity in the projectors and the projection lens mounting; use of
wedge plate holders make it possible to utilize convergent photography without
disturbing the projection lens in its mount. Full-size projectors are used for
photography taken with cameras of varied focal lengths, and still providing four-
or five-diameter enlargement. Super wide-angle projects may be used as well.
KEUFFEL AND ESSER COMPANY.
The Keuffel and Esser (K&E) Company, Photogrammetric Systems Divi
sion, USA, has produced the K&E Stereoplotter, an anaglyphic, projection-type
instrument capable of carrying up to five projectors; capable of performing map
plotting and control extension functions; and capable of accepting digitizing and
computer attachments. Other characteristics are as follows: quartz halogen
projection lamps are long lasting and provide lumination sufficient for operation
under brighter ambient light; utilization of standard wide-angle photography;
5X magnification; and variable sizes of black granite working surfaces.
PGM INSTRUMENT COMPANY.
The OGM Instrument Company, Baltimore, Maryland, USA, has produced
the OGM Hotter which is a projection-type plotter utilizing either the Anaglyph
or Stereo Image Alternator (SLA.) principle of projection. Its characteristics
are as follows: 5X enlargement projectors (up to four projectors per bar); wide-
angle image format; range setting of principle distance; working surface con
sisting of a granite slab} minimum resolving power of lens is 16 lines/mm; and
minimum light transmission is 5. 0 footcandles.
INTERNATIONAL BUSINESS MACHINES CORPORATION.
The International Business Machines (IBM) Corporation, Kingston, New
York, USA, has produced several allied equipment items and image processing
systems utilizing digital computers.
a. IBM Special Cartographic Scanner. Equipment and programs to assist
in computerized resource mapping have been prepared for the Agricultural Re
habilitation and Development Administration (ARDA), in Canada. Basically, the
equipment consists of an optical drum scanner, capable of scanning a wider range
of resource map materials and line widths. Scanning is accomplished with eight
spots, set in parallel, capable of covering a relatively large area in one incre
mental scan. About 10 minutes are required to scan an entire map sheet. During
that period, millions of bits of data are scanned and recorded on a reel of mag
netic tape. Drum rotating speed during scanning operations is maintained at a
constant level. System accuracy is determined by rescanning and recomputing
distances between the centers-of-gravity of any two random line closures. Closure
distances are limited to one spot width.
b. Image Processing System (IPS). IBM and Link/General Precision
Corporation have collaborated in the development of an Image Processing System
