Bad / Good compass calibration

[Dima]

Hi,
I've seen many posts here mentioning "bad" or "good" compass calibration. What exactly bad and good means? My anderstanding is that the green lights should flash on successfull calibration. If they didn't - that's a failure and you need to recalibrate again. Or maybe there is more to it I don't know about? Thank you.

 

[Wingfan04]

Compass Calibration, A Complete Primer | DJI Phantom Forum

 

[Wingfan04]

Pretty much All you need to know is in that post

 

[Meta4]

A good calibration is one done in a good area well clear of large iron or steel items including buried pipes or steel reinforcing.
A bad calibration is one done somewhere the normal magnetic field of the earth is distorted by iron or steel somewhere nearby.
Adjust your compass so it thinks it's correct in a distorted field, and when you fly away from the distortion ... your compass is still trying to correct for something that's not there any more ... bingo .. flight problems.

 

[mknmd]

Only bad one I ever had was taking off from a concrete patio, suspect there was iron rebar or mesh in the concrete

 

[msinger]

suspect there was iron rebar or mesh in the concrete

Yep. You should not calibrate the compass near concrete and/or take off from concrete.