Accuracy of a trace
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Accuracy of a trace
On a short hike yesterday, the precision is sometimes excellent and other times a difference of 3 to 4m, this distance seems normal, but why the differences on a circuit yet without trees or houses, completely clear and beautiful sky.
GPSMAP66sr, GPSMAP67, GPSII+, Twonav Cross.
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Re: Accuracy of a trace
I also notice that the deviation is considerable, but the line is straight and the distance is even. The track does not move like a snake. Unless that's how I move.
GPSMAP 67, GPSMAP 66sr
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Re: Accuracy of a trace
I notice this inaccuracy by staying in the middle of the road or the path, sometimes an offset of 3 to 4m measured on the Google Earth map which I think is precise, likewise on the IGN satellite map of France.
But the precision tolerance for a good GPS is around 3m in the case of the 66sr in multi-band.
On the other hand, if I ride a bike, with any GPS like my old Edge 705, the track is perfect, is it due to the speed, certainly.
But the precision tolerance for a good GPS is around 3m in the case of the 66sr in multi-band.
On the other hand, if I ride a bike, with any GPS like my old Edge 705, the track is perfect, is it due to the speed, certainly.
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Re: Accuracy of a trace
I think so too.
You should not compare yourself to the map, but to previous hikes.
Spoiler
I also showed the distance most deviating from the "norm".
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Re: Accuracy of a trace
The IGN France maps are very precise, they are used to create IGN maps at 1/25,000, this is the reference and I have exactly the same offset as on Google Earth.
There is a geodesic system in France precise to the cm, we can access the terminals and markers, their positions and their precision.
There is a geodesic system in France precise to the cm, we can access the terminals and markers, their positions and their precision.
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Re: Accuracy of a trace
I have been creating my own maps for more than a decade, frequently comparing my data to Google Earth satellite imagery, and have found their satellite imagery to shift inconsistently in random directions by several meters from one release to the next.mimichris wrote: ↑Thu Apr 06, 2023 9:09 am The IGN France maps are very precise, they are used to create IGN maps at 1/25,000, this is the reference and I have exactly the same offset as on Google Earth.
There is a geodesic system in France precise to the cm, we can access the terminals and markers, their positions and their precision.
Any map that is aligned precisely with Google Earth satellite imagery today will not be aligned precisely when compared to future or past Google Earth satellite imagery releases.
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Re: Accuracy of a trace
IGN satellite :
*** Hotlinked image removed ***
Google Earth :
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Google Earth :
*** Hotlinked image removed ***
GPSMAP66sr, GPSMAP67, GPSII+, Twonav Cross.
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Re: Accuracy of a trace
I did not understand how to load images, although I make you delete them, how to do please!
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