Offline maps in 'Alpine Quest' & 'All-in-one Offline Maps +'

[Longjohn]

Dear Sir,

I have the full versions of both apps and have some saved maps for All-in-one OM+ that I would like to use for AQ. The map I use most of all is the Swiss map which provides excellent coverage of the footpaths in Switzerland and has all the height contour information that you could wish for.

I saved the whole of the Swiss map just after I bought OM+, and I used this regularly and it was very reliable. I then wanted tracking, so I then acquired the full version of AQ. I thought it would be easy to use my saved version of Swiss for AQ, and I thought I had three options:

1) Use the same map storage directory for both apps. Unfortunately, try as I might, I could not change the directory file paths for one app to be the same as that of the other. In fact, I could not alter it at all.

2) Copy the Swiss map (450 MB!) from the OM+ directory into the default AQ directory. However, AQ is not able to detect the stored map. I don't like doing this, because the two copies of this map now take up 900MB of space!

3) Go through same download and storage process for AQ that I had originally followed for OM+. This seems rather wasteful if I already have a copy stored for OM+. I tried this, but got too many errors.

Please tell what I am doing wrong. The two apps are so similar, it must surely be possible to share map storage directories.

Another issue I have is that when I track, the resulting Elevation vs. Distance profile does not show elevation, even though this parameter is quite clearly being displayed when I walk.

Look forward to any advice you can give.

Kind regards,

Long John

[Psyberia-Support]

Hi and thanks a lot for your support.
The only way I see is to move the cached data from OM to AQ. You can copy them like you try to do, but yes it will consume useless memory. Since all features of OM are included in AQ, maybe you should use this one.
To do so, try this:
- add the topo map in AQ;
- move both 'COM.9.AQX.CH_OUT.IDX' and 'COM.9.AQX.CH_OUT.DAT' files from OM (folder 'OfflineMaps/cache/custom-maps/') to AQ (folder 'alpinequest/cache/custom-maps/'). Replace the files if they already exist.

Concerning the missing elevation, in the Location Tracker panel, try to click on the graph to get more stats, then click on the 'Fullscreen' button under the graph, and finally click on the left of the screen to change the axis and choose 'Elevation'.

Let me know if you have any issue.

Best regards

[Guest]

Dear Alpine Quest,

You will not believe this, but when I click on the vertical axis of the tracking profile, I can not select 'elevation' from the list.

The item above two places above 'Profile' is called 'Elevation (Geoid)'. Underneath this title, it states 'Total: no elevation data...'.

I know that the height was available along with the other GPS location data throughout my walk, so why was it seemingly not recorded? It does not seem to be present on the saved track either.

Is there a bug in your software?

Thanks for you prompt response and best regards,

LJ

[Psyberia-Support]

Hi again,
Since you get this message yes it seems that the elevation hasn't been recorded.
I have too few information right now to tell you why, maybe you should make another try. Be sure to clear the Tracker data to remove the track without elevation first. Then, after few locations recorded you should see if the elevation is here.
Be sure to have your GPS turned on. You can also change the Tracker settings to force the app to only use the GPS (default is auto), so it don't use network locations that don't have elevations (maybe it's what happened). Here is the online help: http://www.alpinequest.net/en/help/1.4/tracker.

Did you managed to get your maps in AQ?

Let me know
Best regards

[Longjohn]

Thanks very much. I will try as your suggest, and see if I can get the elevation to show.

One point I did not mention is that when it was refusing to display the elevation data, the Y axis name 'elevation' was in red.

I note that once I displayed another vertical axis (e.g., pressure), it was not then possible to re-select 'elevation' as the axis parameter from the Y axis selection list. 'Elevation' was simply not shown.

Yes, I did manage to get my offline map to display in AQ. I had only copied the *.dat file and in any case had put it in the wrong directory!

Look forward to any response,

Regards,

John

[Psyberia-Support]

Hi again,
The red if the display color for the elevation on graphics, so it's OK.
Let me know concerning you new tracking.

[Longjohn]

Dear Sir,

I followed your advice and managed to record the elevation during a walk by having the GPS as the only location method.

Another strange thing: I knew very well what the elevations were on the route I was following and was impressed when I noted that the instantaneous value recorded on the Alpine Quest map view was very close to that given on the map.

When I looked at the tracking profile at the end of the walk, it appeared that about 50 metres had been added to the height.

Is some correction being applied according to the theoretical shape of the Earth's geoid? Why not just use the direct GPS values without correction?

I'm not convinced by your claim that barometric pressure could be a more accurate way of measuring elevation than the GPS. If you were engaged in a long hike, then the Sea Level pressure could be changing dramatically in the space of a few hours.

How does this feature work and how do you apply corrections for diurnal pressure changes? Or do you assume that because most walks are usually short, you can record the pressure at one known height and then record elevation changes relative to this value?

Kind regards,

Long John

[Psyberia-Support]

Hi again and sorry for the delay.
Yes all elevations given by the GPS are corrected (they need to be). As you seems to know, the GPS elevation is the altitude over the WGS84 ellipsoid, not over the Earth. AlpineQuest uses the EGM96 model to correct elevations.
Here is the online help about his subject: http://www.alpinequest.net/en/help/1.4/geolocation

Note that all elevations are corrected, the instant ones and the one recorded by the Location Tracker.
Also, note that the Location Tracker just takes the instant locations and stores them. They are all the same locations, nothing more or less is done in the Location Tracker, so you should not have any differences between instant locations and the one recorded by the Location Tracker.

Concerning the barometric elevations, it's based on the fact that:
- GPS elevations are not precise locally, but will remain stable in time;
- Barometric data is precise locally, but will derivate slowly with time.

The application uses both data to extract a precise and stable elevation. In practice, a sea level equivalent pressure is extracted from the GPS data every quarters, which is used to calibrate the barometric data. Note that you can change the Y axis of graphics to display the raw pressure as given by the barometer, but also the extracted sea level pressure.

Let me know if you have any question