Hello, I have a question about the mavic and boat and compass. I ll go on cruise boat diving.I planned to take my mavic on this cruise. My question is how is going the calibration compass on the boat ( made of metal). Will I be able to use it confidently , or will it make the mavic unstable. I didn't really want to see the bottom of the water in the first takeoff. Thank you for your answers. Fred

I would suggest you just don't calibrate it. I don't think I've ever been asked to calibrate my compass, even with dozens of flights and in two different countries (Australia and Philippines). But to be safe, I would suggest trying out the Mavic on dry land in the same region as where you'll be cruising. If it asks you to calibrate, do it. If not, just test out the flight characteristics. Make sure it hovers and moves exactly as it should, indicating that the compass calibration is fine.

I've had it on a few instances where i get compass errors on the ground due to metal but then as soon as it's in the air it's ok. Just hover and make sure you get full gps lock etc. I saw it first when i was on concrete which must have had alot of steel reinfocement.

I concur with both comments here. I've not calibrated a thing in a month of ownership (except the gimbal).

Every time I switch the drone on indoors (to play with settings) I get a compass error. I take it outside and no error. On a sea wall (iron shuttering) I get an error. 10meters from sea wall,  no error.

Oh yeah, as Will and Peter have suggested, I was about to come back and add that if the boat is metal, or has a lot of metal, you might get a compass error on deck, but once you take off and move the aircraft away from the metal structures, the compass errors should go away. DJI-Ken made this recommendation in another thread with regard to launching from rooftop locations.

When you have first turned on your controller and loaded up the Go 4 app, then when you power on your Mavic and the 2 devices have connected the blue "Go Fly" button appears bottom right on the app.

When you select go fly there is initially an information screen overlaid over the camera view showing you the status of various parameters of your Mavic. The top one informing you if you are on the latest firmware.

Just underneath the is an entry for Compass state, it usually says "Good" and there is a DETAILS button next to it. If you press this DETAILS button before every flight it will open the "Sensors State" view as shown in the link below. It shows the state of both Accelerometers (IMU's), Gyroscopes & compasses in a graphical manor with coloured horizontal slider bars. In the screen grab I have attached I didn't have my Mavic connected and the length of the green bars is actually a lot longer than I normally get before take off in a perfect area with everything all calibrated and no interference. There is a little blue dot next to the Accelerometer, Gyro or compass that your Mavis is actually using (usually 1)

If you are getting any interference or put the craft near a metal object the length of the slider bars increase and also change colour through yellow to red in severe cases.

Sensors state

This is a very useful visual check you can do of your sensors before each flight. I have read on these forums so many times of folks doing many calibrations, when in reality if you just check this screen you can see if you need to or not and if your compass is experiencing any interference.  It only takes a few seconds to check and is quicker than actually doing a compass calibration.

thanks for your answers :-)