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Altitude Offset

Discussion in 'DJI Ground Station' started by RickD, May 22, 2014.

  1. RickD

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    Amongst other issues I'm trying to get my head around with the PC GS is the altitude offset. In the Syst Setup menu, there is the alt offset options. After reading and rereading the manual, I'm still in the dark. What exactly does " offset" mean? There is a height and elevation option. Height is altitude at ground level (AGL) and elevation is altitude from mean sea level ( Msl), right? If so, then what do you do with the recommended offset? Add that number to the altitude for each waypoint for the mission in the Editor? I'm flummoxed.
     
  2. Ozzyguy

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    Location:
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    First of all let me say I don't have or use the Gs feature. I will have a guess though and get the conversation moving(Others feel free to correct me if wrong).
    Say you set your height at 400 feet but your route takes you over a 400 foot hill. But you want to maintain 400 feet above ground height. set the offset to 400 feet for this area perhaps so your phantom doesn't smack into this feature?
     
  3. RickD

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    Thanks Ozzy, I wish it were that obvious. The DJI GS manual does address this and I wish it was so clear and obvious. But the Chinese to English translation makes no sense to me. A normal recommended offset for my area is 297 meters when set to altitude. That is almost 1000 feet AGL. But if set to height it is only 3 meters. I may have a 100 ft obstacle in my mission plan but that's it. So I would be busting the FAA's 400 ft rule to fly a mission using the recommended altitude offset in an area that it is not needed. Or I would be in the trees if using the height recommendations. Or I'm a complete idiot and just don't understand DJI's straightforward user manual.
     
  4. Tahoe Ed

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    If you look at the example, think of taking off from a building. The offset is the difference between your takeoff height and ground level. AGL and MSL are not part of the equation. Ground level is ground level but you may not be taking off from ground level, therefore you need the offset.