Author Topic: Base map on Etrex  (Read 1409 times)

alfapete

  • Oh dear
Base map on Etrex
« on: June 01, 2014, 04:46:59 pm »
I've got a new Etrex 30, have read these pages, and aukadia (thanks Francis!) and am very grateful for all the guidance - goodness knows how you manage without all this.

I've managed to upload and download tracks and am learning my way around things, even completing the Silk Run 100 yesterday with no problems following the pink line (and even used Proximity alarms for info controls!). However, the Garmin Basemap (currently have no other maps loaded) are about 300m out of place which does not cause a problem, but it can be distracting. Is this something I've done, something I've NOT done, or something I should expect?
alfapete - that's the Pete that drives the Alfa

Kim

  • Timelord
Re: Base map on Etrex
« Reply #1 on: June 01, 2014, 06:03:46 pm »
Maps out of place is usually a symptom of a datum mismatch.

That said, having switched to the basemap on my E30 and tried likely datums, it does look like it could be off by that much (hard to tell without going out and trying to follow one of the roads on the map).

I suppose the basemap could just be that bad (it is trying to cover the whole world in one map).  I highly recommend uploading an OSM map or something instead.  They're much more useful.
To ride the Windcheetah, first, you must embrace the cantilever...

Phil W

Re: Base map on Etrex
« Reply #2 on: June 01, 2014, 06:23:09 pm »
300m sounds like the difference between OSGB datum and WGS84 datum. Is it the base map in Base camp that has issue or on device.

alfapete

  • Oh dear
Re: Base map on Etrex
« Reply #3 on: June 01, 2014, 06:28:26 pm »
300m sounds like the difference between OSGB datum and WGS84 datum. Is it the base map in Base camp that has issue or on device.

Can't say I understand the jargon in your question Phil, but it's the map on the device that is the problem
alfapete - that's the Pete that drives the Alfa

Feanor

  • It's mostly downhill from here.
Re: Base map on Etrex
« Reply #4 on: June 01, 2014, 06:56:52 pm »
The 'Base Map' may safely be discounted as being 'No Map'.

You need to install 'proper' maps.




Phil W

Re: Base map on Etrex
« Reply #6 on: June 01, 2014, 07:31:01 pm »
You'll want to install OSM or Garmin city navigator maps to,get some decent mapping. Base map needs to be zoomed quite far out, if beyond its resolution is doesn't align.

alfapete

  • Oh dear
alfapete - that's the Pete that drives the Alfa

Re: Base map on Etrex
« Reply #8 on: June 02, 2014, 08:02:42 am »
The Basemaps only give you a rough idea of where you are in relation to surrounding towns and cities.
To get a better idea of where you are, ride along the road and look at a junction signpost, and get the OS map out of your saddlebag.

Installing a decent map like OSM will give better clarifiction of your position. Using the 'snap-to-road' facility will confirm you are not riding in the hedgerow.


frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Base map on Etrex
« Reply #9 on: June 02, 2014, 08:41:55 am »
And once you have a better map installed, I would turn off the terrain shading (actually the default setting is OK as it switches shading off anyway at 'sensible' zoom levels).

I think this is the default datum setting, and I leave it on this.  If you want the comfort zone of Grid Refs then I think it does automatically change the other two settings as well.  Personally I think the sooner we all wean ourselves off Grid Refs or even worse, Postcodes, as a means of defining location, and standardise on lat/longitude, and specifically the Gmaps implementation (degrees and decimal degrees, no minutes or seconds) - the better.

I stayed in a hotel in central France the other night, which was plumb on the French meridian (the Paris version, about 2.3 degrees to the east of the Greenwich one) there was a sad, neglected little obelisk in a nearby park to mark it.
"This is a complex subject, with a need for more than one highlighter pen."

alfapete

  • Oh dear
Re: Base map on Etrex
« Reply #10 on: June 02, 2014, 07:11:30 pm »
Thanks to everyone for their help with this - all clear now.
alfapete - that's the Pete that drives the Alfa

Martin

  • Give me bas relief
    • WWW
Re: Base map on Etrex
« Reply #11 on: June 07, 2014, 07:31:31 am »
I'll put it here too as it seems to be the issue;

something I've noticed is that the City Navigator map on my device does not line up with the basmap that (presumably) comes with BaseCamp as I'm sure they don't hand out anything free, so any routes I create don't line up with the roads on my device 

does this mean I need to get hold of an OSM of the UK or something? the basemap works but is pretty useless for planning rides

is CN 2008 what I originally used with Mapsource (ie the DVD)? on my device (to which I copied the map way back on a micro SD card) it says it's 2009  ???

Re: Base map on Etrex
« Reply #12 on: June 07, 2014, 07:48:08 am »
The Garmin basemap comes on everything.
Its so you can take it straight out of the box, go sailing, lose sight of land and be able to zoom out to see where nearest land is.
Or get dropped in the wilderness, zoom out to see how far Newport Pagnell is.

fuaran

  • rothair gasta
Re: Base map on Etrex
« Reply #13 on: June 12, 2014, 11:29:32 am »
I'll put it here too as it seems to be the issue;

something I've noticed is that the City Navigator map on my device does not line up with the basmap that (presumably) comes with BaseCamp as I'm sure they don't hand out anything free, so any routes I create don't line up with the roads on my device 

does this mean I need to get hold of an OSM of the UK or something? the basemap works but is pretty useless for planning rides

is CN 2008 what I originally used with Mapsource (ie the DVD)? on my device (to which I copied the map way back on a micro SD card) it says it's 2009  ???
Yes, the "Global Map" included with BaseCamp is pretty rubbish.
BaseCamp should read any maps you have on the device, while the device is attached. Though these means you need the device plugged in and switched on to use the maps, and this may be slow. So usually better to install some maps on your PC instead.
BaseCamp uses the same maps as MapSource. So if your City Nav DVD installs the maps into MapSource, they will also be available in BaseCamp.
Or there's a variety of OSM maps with installers for BaseCamp.