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Elevation Values

My online map shows ground elevations in the 330' range. My photos are tagged with 170ish altitude (I assume meters so 560ish'.) I flew at 200' AGL so that difference makes sense. My actual ground elevation should be in the 750' range. Should I expect such big differences without using GCPs? Will using the ground image picture make this much better? I was deleting them until today when I found something about them while researching this problem. 

Joel DiTullio

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Also data collection page states: 

  • Cruising Altitude Images Only - Only images taken at the cruising altitude should be uploaded into the system. Do not upload images from different altitudes like those taken during ascent and descent.

So perhaps the directions should be amended to mention the inclusion of the ground shot?

Joel DiTullio 0 suara
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Yes, GPS derived elevation tags can be off by hundreds of meters. The Ground Reference image would fix this by using the takeoff location's elevation from a 3rd party source and then using the barometric altimeter numbers with the offset. 

Zane 1 suara
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