Just wondering how to measure height of each spot after processing map or do any function to let us measure each spot height from sea level?
You might check these documents out on that on the FAQ page.
Am I right in saying that for example, if there was a wall height that you needed to measure from the map, you would use the measurement tool to draw a straight line at 90• across the wall, and then get the height measurement from the elevation profile? Keeping in mind that ground zero (0m) is the take-off location of the drone.
You use the calibration tool to set the elevation of the whole map according to a point that you know the exact elevation for. You can then use the location pin or the distance measurement to get elevations.
In the past when I have calibrated the map, I have recorded the “take-off” point as “0m” for the height. For the most accurate information, does it matter that the camera is actually 10-20mm off of the ground?
If I use a GCP as my “take-off” point, do I need to take into account the distance from the ground/surface to the centre of the camera, even though it is a few mm?
That should actually be measured from the GPS sensor which is at the top of the Drone. Wherever you take off from and the altitude that you’re flying at is 0. If you have a known Benchmark or something with an elevation on the map you can use the calibrate tool which is in the top header project information to adjust the entire map to that known point.