[chromvis]

Need help.
1.  For two days I am struggling with external Mag/GPS calibration. Finally got everything OK. Both mags are green, board level calibrated, accels calibrated, RC inputs calibrated (trims - 0), but Quad flies tilted forward and right for about 15 - 20 degrees. (Pics 1 and 2). (Nighthawk200 with revo and DJI GPS/mag) What is wrong?

2. Second quad (NH-280 clone with revo and Ublox GPS/mag) Mag calibration is OK (actually, first pic is for this quad), but model view does what is shown on next video (.avi file attached). I did not dare to fly it. All calibrations were done several times. I check all possible parameters. What is wrong here too?

[f5soh]

The two Mags (onBoard / AuxMag) are not sync, look at the 2 bars that do not show 0 (centered slider)
Same with scope, the blue / light blue and green/light green traces are not sync.

Seems your Yaw orientation is not fine because X and Y axis show a misalignment.
Try -90, 0 or 90° for Yaw, assuming the GPS arrow is not oriented randomly.

Video that show a inverted PFD can have the same cause.

[chromvis]

Thank you. I, kind off suspected that. The best what I could get is synchronized but shifted responses on scope not identical as in your video. Is there any trick to get them practically in overlay?

Also, If I one uses AuxMag (Aux only set) why do we need account for onboard mag at all? Since it is the most vulnerable for errors, it should be logical if I select Aux only setup, on-board mag should not have any influence, but it does, it seems like a bug or rather systemic error, isn't it?

[f5soh]

The onboard Mag is only used as reference for AuxMag orientation, onboard Mag works perfectly since you don't start motors.
Of course for flight you may use the AuxMag only.

If Mags are not sync, that a AuxMag orientation error.

To double check, switch Fusion algorithm to INSIndoor:
1 - Check if compass value in PFD matches the know North using Auxmag usage set to OnBoardOnly 
2 - Do the same with Auxmag usage set to AuxOnly

Anyways, according the the scope you posted, X / Y axis error seems close to a 90° error.
Simply try -90 or 90° for Yaw.

[TheOtherCliff]

There was a bug in the old GCS it did not remove the aux mag board rotation before calibration.
The new GCS temporarily removes aux mag board rotation during calibration.
I think the issue is that you can't use the scope to compare aux vs. onboard mags during calibration anymore.
You should be able to do that after it is calibrated though.

Another minor issue is that the aux mag can be mounted a few degrees different than the Revo.  The best way to adjust for that is to use Basic with Attitude mode, and adjust Rotate Virtual for motionless hover (no wind).  Then use INS13 with Attitude mode and adjust Aux Mag board rotation for motionless hover (no wind).