Os Maps...

[+timotab]

Just curious - as an expat Brit living in the US, I decided to look up a few caches near my parents.

 

I went to "map it" and found there was no map!

 

I uploaded the waypoint to my eTrex, changed the co-ordinate system to "British Grid" and it gave me a two letter + 10 digit OS reference (accurate to 1 metre). I went to the OS website: http://www.ordnancesurvey.co.uk/oswebsite/getamap/

and typed in the reference, and there it was, just as described in the Waypoint info.

 

Do Brits use the OS maps like this? Do you tend to convert hddd:mm.mmm' style to Ordance Survey style? Or what do you do?

 

Timothy

[+Naefearjustbeer]

As far as I know the OS grid uses a different map datum to from the Lat & Long quoted on a cache page WGS84. For caching purposes I tend to leave my gps set to wgs84(datum) and hddd mm.mmm. (position format)

When I am going off of the beaten track using OS maps I will select my etrex to British Grid(position format) and ord srvy gb(datum) and switch back when caching.

This is the recognised system that the mountain rescue etc all use and they would locate someone using this format. I believe there can be quite a difference in position between the 2 datums.

 

I send all my waypoints to my gps when set to wgs84 and hddd mm.mmm for caching and once they are stored in your gps your gps will do the correct conversions between the datums and keep you pointing at the right place. If you change to the british grid system

[+Chris n Maria]

The easiest way to find where a cache is on an Os map is to go to http://www.geocacheuk.com click on stats then caches and do a search.

In the list that comes back Grid Ref is a link to streetmap that will show you an os map. Clicking on the cache name shows the cache details and any lat/longs have the os reference shown next to them as a link to streetmap

 

For mass conversion take a look at Waypoint Workbench which will take loads of different file formats & generate os coords & links to streetmap & multimap.

 

Quite a few people use memory map to plot waypoints and route on to os maps.

 

Chris

[+timotab]

Thanks, that's interesting.

 

I forgot about the different data

 

I will have to remember all that when I next come to England and want to do a few caches.

 

Timothy

[+choccymandm]

As we're not the most techy cachers in the world (eMap and thats it!) we've become big users of getamap. Streetmap is ok for urban caches but as most tend to be out in the country the OS's getamap is much better - contour lines, footpaths, tracks, terrain info, etc

 

We tend to stick with gc.com when looking for caches as it has all the info we need OS grid reference, Lat/long then have getamap running as well to see exactley where it is where going! Out on the road - GPS set to WGS84 and a mini OS map print courtesy of getamap! (sure does beat the days when we would "cache blind" ie. follow the arrow with no real clue where we were going!!!)

[+Mr & Mrs Hedgehog]

emapsite.com is good. Bit tricky to use it, but it has the OS maps, contoured etc