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Lake 301

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


301 Lake

Large areas of water are shown with a dot screen. Small areas of water should be shown with full colour. A black bank line indicates that the feature cannot be crossed.

Colour: blue 50% (60 lines/cm), black.

Bank line width 0.18mm

ISOM 1990 Definition

Large areas of water are shown with full colour or a dot screen of at least 50%. Small areas of water should be shown with full colour. A black bank line indicates that the feature cannot be crossed.

OCAD Methods

The default OCAD file uses 301.1 as a bank line (0.18mm black) and 301.0 as the infill blue colour. This blue is a 50% tone. If full colour blue is needed then use 302.0, the pond symbol as the fill.

The default blue fill may be drawn with any drawing tool, but the bézier tool is the most efficient. As the defined colour will overprint all others, but will not knock it out there is a need to cut out an underlying symbol. This is particularly the case with yellow and green, but also applies to other symbols.

Remember to draw the bank line around any islands. (Holes in areas can be independently selected and the bank symbol added with the outline/fill tool).

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.

Drawing Considerations

A black line round a water feature indicates that the feature cannot be crossed under normal weather conditions. The line is broken where the water may be crossed see 304.

See minimum dimensions but specifically -

- Smallest area of colour

Blue full colour: 0.5mm˛

Blue dot screen: 1.0mm˛.

Pictorial Descriptions

- BOF Rules, Appendix One

A significant area of water, normally uncrossable.

The problem with colour clashes is that the screen and composite (local printer) output does not necessarily reflect the separated output.

If you digitise your map in the same way as you would draw it, that is, you cut out all underlying objects beneath the blue, then there is no colour problem (greening of the lakes).

There are alternatives, the most common method is to make the blue colours automatically knockout the lower colours. To do this, you have to change the colour table. Put zeros ( “-1”'s for OCADv5) in the blue row in each colour column that you want to knockout. Only the colours lower down the colour table are affected. So there will be no effect on symbols using black and street colours.

There are more details in the Main Help File or in the Colour Help file.

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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