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Can incorrect cache altitude statistics be corrected?

0 votes
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I notice that the Project-GC stats show incorrect elevations for several local caches.  How can incorrect elevations be reported/corrected? I'm particularly annoyed because two local caches which were/are below sea level are should be shown as being well above sea level.

Two caches which should be shown as below sea level:

Getting the Good Dirt GC28FKD  - This cache is at minus 2 m.  {See this topo map http://wams.org.nz/wams_desktop/index.aspx which shows the area near Dunedin airport below sea level.)   Project-GC wrongly shows the cache as being 4 m.

Urban Macro peer Review GCYD7F - This was hanging from a pontoon 1.5 m below sea level.  Project-GC wrongly shows it as being 4 m

Obviously puzzle icons out at sea are shown as being at 0 m elevation. But these are some puzzle icon elevations which need to be corrected on Project-GC:

Pick a Path GC26C37  which should be a "sea level start icon" but is wrongly shown as being at minus 15 m.

All the puzzle icons on Lake Waihola, eg Knowledge is Precious to Me GC65029 . Lake Waihola is at sea level, 0 m. However, all the puzzle icons are wrongly shown as being minus 1 m.   

The reason for my question - I've been thinking of creating a challenge cache including a "below sea level" requirement.  (Puzzles and multis  would not be included because the start icons don't reflect the cache elevation.) However, this change to requiring a 'challenge checker'  makes an 'altitude challenge' impossible because  the Project-GC stats are incorrect for the two local caches which were or are actually below sea level.
asked Jun 11, 2016 in Bug reports by daywalk (120 points)

2 Answers

–1 vote

There is FAQ explaining the case:

I found a cache with a faulty elevation

[...]

We do not do manual changes in the data. But if you find an entry that seems to be off by a lot more than in other services, feel free to report it so that we can investigate.

I believe, if you would find some reliable (and available) source for elevation data, it could be incorporated in the tool, but otherwise it is not possible to adjust  single caches AFAIK.

answered Jun 11, 2016 by Jakuje (Moderator) (89,360 points)
0 votes
I'm not sure which elevation model is used for NZ in PGC actually, but there is a free 15m elevation of NZ available. It is downloadable from http://www.otago.ac.nz/surveying/research/geospatial/otago040574.html

Due to the nice situation that NZ hasnt any boarders to other countries I think it should be easily to replace this DEM, because you havent to pay attention to other DEM which can maybe overlap the area.

If you need help to convert the data into a specific fileformat, give a me sign.
answered Jun 12, 2016 by smellfooth (3,250 points)
As noted just one FAQ below the linked one, PGC is using SRTM1 and SRTM3, which has measure 30x30 meters in USA and 90x90 elsewhere. Certainly having more accuracy would be good progress. Lets see what ganja will say about that.
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