With the camera installed and the drone powered up, turn the aircraft over on its back and watch the gimbal. If the gimbal is bumping, jumping, and does not seem happy, it wasn't designed to deal with those angles and positions. Remove those gimbals for the compass cal. Most camera gimbals are not designed to function inverted and have electronic or physical stop limiters built into them to prevent over rotating.
When I first purchased the H back in March 2017, I didn't know this Forum existed, I didn't have all the info that's provided here, and I never owned a drone before the H!
Being a pilot helped me understand the dynamics of flight, especially rotor crafts.
At the time I didn't know better about taking the camera off, I didn't. On my madin flight I only flew several feet agl for several days.
Kept it close to me for weeks until I was comfortable going higher and farther out.
It's all about being smart of what you have in your possession, knowing both the limitations of yourself and the drone.
Oh, and I calibrated it with the camera attached, just like the video showed that came with the H.
Last post was nearly a year ago, but here's hoping I can piggyback on this thread with my question...
I get a message to calibrate my compass nearly every time I fly (3-4 days per week), and most flights are in the same location. What might that indicate?