[closed] Elevation display on AQ

[pinkyperk]

I am a bit puzzled about the elevation levels shown on a imported route, which seem to be at variance with the true level (as shown on the map) and the levels in the gpx file. As an example - I create a route / track using memory map. I later add elevation data using a pc program and then import to AQ. I can display the map correctly. On the example shown below, I am displaying the OS map showing the mountain peak Wetherlam which is 762 m on the map. Looking in my gpx file with text editor, the elevation is shown as 752 m at this point (Waypoint 77), and this is approximately correct. On AQ using Dynamic profile at this particular point (which is the highest point of the track), it shows the elevation as 577 m and computes the highest point 627 m about 100 m South West. But this figure is still 130 m lower than the actual elevation. If I click on the map at the same point in AQ - on the pop up it shows Location 77 +701.

screen shot AQ.jpg

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This is not an isolated situation, though the differences in elevation between the displayed elevation and the elevation shown in the gpx file vary according to which track I am using. I use the dynamic profile quite a lot. It is handy to see what climbing or descending is coming up, but at present the figures are somewhat confusing. I would be grateful for your help with this. I use AQ a lot and welcome the updated AQ2

[Psyberia-Support]

Hi,
It seems to be the same "problem" we already discussed about here.
It would be better if you could put your track in a KML file, which contains "real" elevations and not GPS elevations.
Let me know if you think there is something else.

Edit: I'll try to include some options when importing a GPX file so the use can specify the type of elevations withing the file, so you won't have this problem with GPX files too.

[pinkyperk]

Thanks for your reply. I have now tried to look at same situation by converting the file to KML. See results in table below where I have compared the data when the file is displayed after importing as an gpx file or kml file with the same elevation data contained within each - and also comparing with the actual elevation figure contained within the file based on the DEM lookup.

Screenshot_table.png

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Although the KML gives more accurate elevation levels when clicking on a waypoint (i.e. popup on screen), there is still a discrepancy when displayed in the dynamic profile. Here the elevations levels are shown as being significantly lower and there is a shift such that the highest point is not shown in the correct position.

It would still be good if gpx tracks and routes could show accurate elevation data in AQ as these are commonly used types of files in other applications. Thanks.

[Psyberia-Support]

Ok so now you've something coherent when you click on the map (the elevation is just rounded on the meter).

Concerning the elevation profile, there's something else going on, even if I found the difference a bit high.
Before displaying profiles (and statistics), the application smooths the data to remove spikes and noises. That's why you don't fine an exact match between the profile and the track displayed on the map.
You've two options if you want to get better results:
- Disable the smoothing: set the "Noise reduction" setting to "None" in the "Statistics settings". The dynamic profile should then give much closer values, but you may still found little differences because the app sometimes groups locations which are very close the ones to the others);
- Instead of "Dynamic profile", select "Edit profile". In this case the application displays the profile of the raw track values so users can delete particular and exact locations. You'll then find the exact matching values (it seems to be what you want).

Let me know it's coherent with what you find.
And sorry for the troubles, all this is quite tricky...

[pinkyperk]

Thanks for sorting this out. I had assumed that the smoothing was just for recorded tracks. Turning it off gives me accurate elevation figures with the track imported as KML, though with GPX the elevations shown in AQ are still approx 60 m less than the actual elevation. Is it not possible to have them all equal as the same elevation data is contained within both the KML and GPX versions of the same route?
Anyway, I also look forward to the planned feature of adding elevation to routes created in AQ, this will be really useful. I appreciate all the work put into making this a superb aid to walkers

[Psyberia-Support]

Hi again,
Right now it's not possible, the application handles elevations in GPX files as "GPS elevations" and elevation in KML files as "mean see level elevations". You can get more details here.
But I'll try to add a setting in future versions.