Mapping and Drawing Maps
An informative article 'The Use of New Technologies in Making Orienteering Maps' by L Zentai, appears in Scientific Journal of Orienteering, Volume 17, 2009, pages 56 -64, link here
Base maps that may be suitable for an orienteering map include:
- Previous orienteering map
- Aerial photographs
- Topographic maps, with or without cadastral or property boundaries
- Georeferenced aerial photographs
- Photogrammetric plot produced from aerial photographs (film) and using an analogue machine (stero plotter using diapositive films)
- Digital photogrammetric plot produced from digital photographs and digital computer analysis
- LiDAR (Light Detection and Ranging)
- Google Earth
In recent years it has become increasingly difficult to obtain diapositives for use with stero plotters as this method of producing digital elevation models ie contour lines, has been largely superseded by the rapid development and use of digital photogrammetry. This has come about through the development of highly sophisticated digital cameras and the ability of computer software programs to process enormous volumes of data to create contour base maps to a high standard of accuracy.
Digital photogrammetry and aerial photographs can be imported into the latest versions of OCAD. Base maps with a georeferenced grid can then be printed through OCAD at a suitable scale for fieldwork.
It is recommended that orienteering maps, particularly those used for competition, be georeferenced to the regional grid system ie to Geocentric Datum of Australia 1994 (GDA94) in Australia. Not only does this permit the use of GPS, handheld computers and other devices for fieldwork, it will improve map accuracy. GDA 94 is for most practical purposes virtually the same as WGS84 (World Geocentric System) used by GPS units.
There are several methods, depending on the source of data, that can be used by OCAD to georeference an orienteering map and these are described on the OCAD web page under HowTos. A method using Google Earth to georeference an OCAD10 map is described here.
It is now possible to convert an OCAD map for use on a Garmin handheld GPS unit. Details of the procedure are described in World of O: International Orienteering News, 'HowTo: Convert any Orienteering map to a Garmin Map', Jan Kocbach, 11 October 2009, link here.
There is increasing interest and use of LiDAR which can produce highly accurate and detailed contour lines particularly in areas with dense tree cover. A paper published in 2005 discussing the use of LiDAR for creating orienteering base maps by G Lennon, a member of the IOF Map Commission, is presented here.
'LiDAR Links for Orienteering Basemaps' is available at this web_site. An Australian experience by N Barr using LiDAR for two of the Easter 2013 maps is available here.
Several presentations on the experiences of various countries using laser scanning for preparing orienteering base maps may be found here: 14th International Conference of Orienteering Mapping, August 2010, Norway, link. A summary of this conference was presented by A Uppill at the Mapping Technology Workshop, Adelaide, September 2010, presentation here.
Mapping using OCAD
The vast majority of orienteering maps are now drawn using OCAD. OCAD is a commercially available software program for drawing maps, including orienteering maps. Information about OCAD and product details is available at the OCAD home page. Some orienteering symbol sets in accordance to IOF mapping specifications are available at the OCAD home page. Also, when using OCAD9, service updates will automatically update the symbol sets.
An ISOM 2000 in OCAD format has been prepared by Alex Tarr, and includes explanations of all symbols, both ISOM 2000 compliant, and some non-ISOM symbols used in Australia. This file can be downloaded here: ISOM2000_OCAD9_AlexTarr.ocd However it is recommended that the OCAD orienteering symbol sets be used as the default IOF maps symbol sets for maps used in Australia, and with deviations from this to be approved by the OA Mapping Officer.
Also see OA Map Symbols for Orienteering Maps Jan 2004.pdf. This edition is now out of date in respect to symbols used for Mountain Bike and Sprint orienteering. Please note this sheet may be updated once the revision of ISOM2000 is completed.
Applying the mapping specifications
Policy 2.9 of the OA Operational Manual Mapping of Rock Feature provides an explanation for mapping rock features in Australia.
A Danish mapper, Kell Soenniksen, has a site giving practical examples on the use of ISSOM 2007 for sprint orienteering maps.