Accuracy of a trace
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Re: Accuracy of a trace
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Re: Accuracy of a trace
GPX file link :
Last edited by mimichris on Mon Apr 10, 2023 9:42 am, edited 1 time in total.
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Re: Accuracy of a trace
The satellite photos do not come from the same source, the IGN has its satellites and its planes for the photos.
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Re: Accuracy of a trace
Have you studied the trace I sent in the affirmative, have you seen an anomaly.
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Re: Accuracy of a trace
Yes, we did view your track in Google Earth Pro, and moved the 'time slider' to view the track superimposed over many dates back to 2014, and we can see the imagery shift as much as 6 meters.
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Re: Accuracy of a trace
position of the terminal surrounded by the blue line point a of the IGN document below :
Point in Earth:
Point in IGN :
You can see that the geodetic marker is at the correct coordinates on both Google and IGN satellite maps.
map of the IGN document terminal:
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map of the IGN document terminal:
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Re: Accuracy of a trace
I did not specify, the satellite photos are from Mobac which accurately records the orthos from Google Earth and IGN, there is no offset, if I place the coordinates directly on Google Earth, there is no no lag either.
Spoiler
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Re: Accuracy of a trace
I think you may be missing the point.
It does not matter that your choice of satellite imagery matches perfectly with Google Earth satellite imagery because, as mentioned previously, Google Earth satellite imagery does not always agree with Google Earth satellite imagery. Google Earth satellite imagery can shift several meters from one release to the next. So when your data matches Google Earth satellite imagery precisely, it only does so for that release, and will not match other versions of Google Earth satellite imagery that are shifted one way or another.
Please examine these Google Earth Satellite Imagery examples from JAN 2022 and AUG 2022 for the NIZAS II reference point coordinates:
NIZAS II Google Earth Shift
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Re: Accuracy of a trace
I don't agree with you, if you put the mouse arrow on a point (pebbles) of your animation, the pebble is always under the arrow from frame to frame but that's just the change definition that gives this effect, experience it.
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