data reliablity

after driving the same road 4 times “2 one way and 2 back” my data looks almost exact with some very minor fluctuations
then when i overlayed them on google theres a big difference my data seems to be drifted northwest of there data
so i guess my question is is google perfectly correct and somehow my GPS Data is flawed

my data is dead on with Garmin topo v4

Google isn’t perfect. The satellite images might be shifted a few or several hundred meters and even the geometry might not be perfect. In this example satellite with labels you can see this just by comparing the Google satellite image with the overlayed Google labels. Nowadays there’s a difference of a few metres. A few years ago there were older satellite images of the same place showing a difference of more than hundred meters.

i had stopped work on osm till i could varify my data was good and the google maps had me troubled

anyway thanks for clearing that up

to verify how exact your recordes GPS tracks are you can also load them into and display them on different layers like GoogleMaps, OSM etc.

Maybe you can see already differences between them.

Don’t use Google for reference purposes as their imagery isn’t precisely orthorectified. Maybe you can find some aerial orthophotos of your area of interest, even outdated?

i found some local benchmarks and tested my unit its fine

google maps are nasty, out as much as 300 meters here