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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.
     
  6. Mogmen

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    Does anyone have a solution for fixing in incorrect altitude data in the exif?

    I tried my i1 with my x3 today and took 300+ images and they we all off by 160'. It consistently showed 280' in the exif when i was at 120' AGL. Is there a fix?

    Is there a program that i can use on my PC to change this data without changing each individual photo.

    Last year on my aircraft i was not having this problem. Does anyone know which FW update caused this issue and is it possible to go back and change the FW. I read where you can but now sure how many versions i can go back to.

    Thank you
    Ed
     
  7. bluelight.support

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    I use EXIF Editor on the mac and batch process my I1 images - just change from below to above sea level and it works fine. If I need anything more accurate, I just add GCP and go from there.