Nav Man - Digital Mapping Tips

Nav Man Lyle Brotherton, never knowing caught out without knowing his magnetic declination...

Lyle Brotherton is a search and rescue instructor and navigation professional. He trains search and rescue teams and special forces worldwide in the intricacies of finding their way in the wilderness and more. He's passionate about navigation and about helping to keep people safe in the outdoors.

And the good news is that Lyles going to be contributing regular tips to OM to help keep you on your chosen course. Lyle is the author of the new Ultimate Navigation Manual and has his own web site at www.micronavigation.com where you can find out more about him and check out some sample pages from the book.

Digital Mapping Definities

This week, two important pointers when using digital mapping:

Make Sure It's Up To Date...

If you use online digital mapping sites to plan your outings, it's worth remembering that while many mapping sites contain OS 1:50 000 & 1:25 000 mapping, they do so by keeping licensed copies of the data on their own servers, rather than direct links to Ordnance Survey. This means that this data can be perhaps a year or two out of date on these third-party websites.

For the latest definitive mapping data, always go to the national mapping agencies free map websites. In the same way if you are buying digital mapping, check with the supplier how old the data is and download it rather than buy it on a CD, this too could be quite old.

Include The Magnetic Declination...

Always remember to include the local magnetic declination on digital maps you print as well as the grid (meridians) so you can give a grid reference, especially if you need help to be able to get to you if you have a problem!