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METADATA ALTITUDE IS TOTALLY OFF HELP!

Discussion in 'Inspire 1 Help' started by bostonkiter, May 1, 2016.

  1. bostonkiter

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    For some reason, our exif files now show bizarre altitude readings. They're now "below sea level". Does anyone know what gives?!

    THANK YOU!


    This is what it looks like...
    metadata.png
     
  2. southerndoug

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    I noticed this when I was using Map Pilot for survey work. The exif data does not use the barometric altitude, but might be using the GPS altitude, which is notoriously bad. The Maps Made Easy guys said DJI was aware of the problem as was going to address it. They probably haven't....
     
  3. The Editor

    The Editor Moderator
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    Not unusual for GPS altitude data to be out by +/-400 feet.
    Depending on the DOP error at the time this can easily average 75 feet in either direction.
    GPS height data should not be relied upon as nearly all manufacturers base their altitude measurements on the elipsoid from centre orbit. Since the Earth is nowhere near round this model is flawed and so you will always get height/altitude errors in the data.
     
  4. bostonkiter

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    Thanks for the response.

    Point taken regarding the GPS vs Alt accuracy with HDOP in mind. However, the metadata was never incorrect until now. It's as if the inspire stopped using the alt to populate the altitude and started using GPS in its place. This is very troublesome as we depend on this for industrial application. Please post if you have any further info.

    THANKS!
     
  5. NickOfLeeds

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    Did you get to the bottom of this by any chance?
    I have just started to realise that this may be causing me a problem.