Erroneous speed data in track record graph
In the first part of the graph that shows my speed during my walking tour, the graph shows 8 km/h speed, which is excessive, and I know for sure that I didn’t walk so fast.
After a given point, the graph shows real values for speed.
I’m not sure what the cause of this problem is, but I have a guess.
I’ve selected the command: “Fill elevation”, because I have downloaded all the .HGT elevation data beforehand, maybe 6-8 months ago. (On a side note, this is necessary, because GPS-based calculation of uphill/downhill is largely excessive, so I don’t understand why Locus doesn’t have an option to automatically extract elevation data from .HGT files in case those files are present for the relevant area.)
So my first guess would be that there could be a difference in resolution in the .HGT file between parts of the track. (Anyway, I haven’t had a look at the chart before choosing “Fill elevation” so I can’t confirm that this is the cause of the problem occurring.)
I’ve used the paid Locus vector map about Hungary, it that matters. Could be there differences in resolution in that vector map, i.e. e.g. 1:15.000 resolution in built-in areas of Budapest and e.g. 1:30.000 resolution in rural areas? (I’ve started track recording within Budapest, then have left it during the tour.)
If you want me to upload the track file, please let me know exactly where I can find the file on my Android 4.3 phone.
Do you want me to also send you a screenshot of the graph displaying the false data?
All the best,