How accurate will my tracks be if I create them with Google Earth?

[+Macon69]

I have paper maps of Sweden, GPS Utility, and an eTrex H (so no inbuilt maps).

 

So... I could use GPS Utility to digitise my paper maps, and then create tracks which I upload to my eTrex (thus giving me an extremely accurate virtual map)

 

Or I could just compare what I see in Google Earth with I have on the paper maps, and draw tracks / waypoints there, which I then export as KML, convert to GPX, and then copy to the eTrex. (Id be entering the geocache coordinates separately: I certainly wouldnt use the Google Earth overlay for that part).

 

The second approach is going to be easier, and quicker. Its also going to give me tracks which are less accurate. But do you think it would be good enough?

Edited May 7, 2013 by Macon69

[AZcachemeister]

Hard to say.

I would create a 'test track' in a safe area where I wouldn't really need it, and then go out and see how accurate it is.

Google Earth can be amazingly precise, or disappointingly inaccurate depending on the 'registration' in your area.

[+Macon69]

Thanks, AZcachemeister.

[GPS-Hermit]

Any map you use can be off so don't get your self in trouble. Always have a back up plan. When not sure, consult several maps and see if any is really different. Maps can be correct in one part and off in another.

[+Don_J]

I have paper maps of Sweden, GPS Utility, and an eTrex H (so no inbuilt maps).

 

So... I could use GPS Utility to digitise my paper maps, and then create tracks which I upload to my eTrex (thus giving me an extremely accurate virtual map)

 

Or – I could just compare what I see in Google Earth with I have on the paper maps, and draw tracks / waypoints there, which I then export as KML, convert to GPX, and then copy to the eTrex. (I’d be entering the geocache coordinates separately: I certainly wouldn’t use the Google Earth overlay for that part).

 

The second approach is going to be easier, and quicker. It’s also going to give me tracks which are less accurate. But do you think it would be good enough?

 

I draw Google Earth "Paths", save as kml, run them through gpsbabel to convert to GPX and then use Mapsource to upload to my 60CS as tracks. I do this almost weekly for hiking trails in our local mountains and they are spot on. My only limitation is that with this GPS unit, a single saved track can only hold 500 points and it can only hold 20 tracks. Does the eTrex H have a micro SD? I think that greatly increases the capacity.

[+Macon69]

Thanks, all.

 

I'm also limited to 20 tracks with 500 waypoints (I think) per track. However, that doesn't tend to be such a problem: I only store what I need on the GPS for one day's walking: my main repository for my libary of routes is Google Earth.

 

On returning to base, I upload whatever is on my GPS, then wipe it clean again for the next day.