I calibrate it once when new. After that it isn't needed unless you travel a long distance. In Norway 100 km East/West or 50 km North/South.Sorry about my mistake, but how often do I need to calibrate the compass?
To put it simple you calibrate the compass so the drone knows where it is bye reading it's position off the GPS satellites, calibration, I do that only if I travel 150 to 200 miles from my original calibration point, fly your drone if everything's alright then don't worry if your drone starts to drift re-calibrate enjoy the droneThere is no GPS calibration. The compass (aka magnetometer) does get calibrated. GPS only gets information from the satellites.