Incorrect altitude reading

[mph]

Hi, I have noticed this twice now, after flying around for a few mins, I noticed that the altitude was reading incorrectly, it would show it at 0 ft when it was flying at around 10-12ft off the ground in front of me.
I hadn't taken off from a different level.
The first time I noticed it was when I was trying waypoints and flying around and near a tree, when I ran the waypoint operation it would have crashed had I not noticed and stopped the it. I think this time it was about 7ft off.

I guess I need to do a recalibration, but compass calibration seemed fine, and also imu calibration seemed fine. I was running with 19 satellites at the time.
Any ideas ?

 

[rockydog]

The Mavic uses its barometer for height readings...any change in air pressure will affect the readings. It's quite common for the readings to be off by a few feet.

 

[Robbyg]

I assume your talking the height (H) reading and not the V.S reading?

Rob

 

[mph]

Height yes.

 

[maccardiolog]

What would be the difference between the two readings and where in DJI display could we found them? Are there superposabile as values (have to )? Thank you

 

[Kilrah]

Height value is measured through atmospheric pressure, normal to expect up to 30ft or so of variation in a flight.

VS height is at the bottom right in the app and is a precision reading from the sonar sensors, but which only works up to about 30ft above ground.

 

[maccardiolog]

Thank you !