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Open sandy ground 211

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This page contains content from ISOM2000   This page contains content from Ashby Mapping    Mountain Bike-O symbol  revision 05/00

Specifications

211 Open sandy ground An area of soft sandy ground or gravel with no vegetation and where running is slow. Where an area of sandy ground is open but running is good, it is shown as open land (401/402). Colour: black 10% (24 lines/cm) and yellow 50% (40 lines/cm). Dot diameter 0.18mm, spacing (diagonal) 0.45mm (22 lines/cm) See commentary at bottom of this page for an analysis of this specification.

ISOM 1990 Definition

As ISOM 2000 but dot diamter and black percentage altered

OCAD Methods

Defined as area symbol 211.0, and can be drawn with any drawing tool. Care is needed at joins, overlap only where it is safe (usually if it is the same colour and always if it is the same symbol). If you need to share a common boundary with another symbol, draw along the edge with the control key to follow it exactly. This is a rotatable symbol, the pattern of the fill can be rotated with the direction tool and will rotate with the map if the “include symbols” box is checked when the map is turned. This is not the same as using the rotation tool which turns the whole object, but not the fill pattern.

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Drawing Considerations

See minimum dimensions but specifically - - Smallest area enclosed by a dotted line: 1.5 mm (diameter) with 5 dots. - Smallest area of colour yellow full colour or black dot screen: 0.5mm˛.

Permissible Combination of Screens

The ISOM lays down the permissible combination of screens. There is no mention of this symbol in the combination section of the specifications. The inference is that this screen should remain on its own, no combinations allowed.

   Dotted areas

(IOF 211, 402, 404, 412, & 415) There is a problem with the joining of these areas. Where a large area is made out of two or more overlapping areas, one area knocks out the underlying edge. This appears a clean join on the screen but the filled area covers the dots at the join on the output.

Extract from Help Sheet `OCAD TWO' (for ISOM1990 only)

The specification is not so far out as open land with scattered trees & 404 and may be ignored. For the pedantic, the IOF dimensions give a dot density of just under 6%, as against a 10% norm. This can be corrected by:- An increase of the dot size to 0.23mm (IOF 0.18) A decrease of the spacing to 0.35mm (IOF 0.45mm) or a combination, say, Diameter of 0.20mm and gap of 0.40mm The default OCAD symbol has a spacing of the recommended 0.45mm but against the wrong part of the pattern, this actually gives a better dot cover of nearly 12%. Keeping the same spacing the dot size should be reduced to 0.16mm to give 10% cover or the spacing can be changed to 0.49mm to give the same result.

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International Specification for Orienteering Maps produced by the International Orienteering Federation
OCAD produced by Hans Steinegger Software. © 1988-1999 Hans Steinegger. ® OCAD is a registered trademark of Hans Steinegger
This document has been written and coded by Peter Hornsby of Ashby Mapping
Apologies for any mistakes and errors; please inform details of any problems, thanks.
Produced for the Ashby Mapping internet site on 20 November 1997 and 1 December 1999  ©1997-2000 Ashby Mapping
Revised 28 December 1999, 23 March 2000