frankymusik Posted at 2020-2-4 08:45
... it is exactly like that.

It's just the relative altitude, as the difference to the altitude from the starting point.

Is there, and what a way to determine actual distance from the ground? I am new to this and don't want to plow into a creek somewhere

snh07 Posted at 1-9 22:34
Hi all , I am new to drones and have a doubt, I have a Mavic  mini 2  and as per local government guidelines can’t be flown above 15 meters altitude and at 15 meters we get a warning that maximum altitude reached and can’t go beyond that. If I fly the drone from a hill upto 15 meters and at same altitude move it into the valley will the altitude is taken as above permissible altitude and what will happen to the drone? Will it plunge downwards into the valley to maintain the altitude? Thank you in advance and hoping for a reply

You aircraft does not maintain a given altitude over any range, in the scenario you mention, the aircraft will not do anything, it will stay at the current altitude unless you command it to go down or up.

creekkeeper Posted at 5-1 18:40
Is there, and what a way to determine actual distance from the ground? I am new to this and don't want to plow into a creek somewhere[view_image]

You aircraft has no idea where ground is, and no, there is no way to determine the distance from the ground unless you took of from there.

Labroides Posted at 2020-2-25 15:30
The relative height comes from the barometric sensor in all DJI drones.
DJI do use GPS for the Absolute height , but only for the Mavic 2 using recent firmware.
For all others, DJI still use barometer data converted to a nominal ASL height assuming standard atmospheric conditions.

Good info, captain. I'm wondering if, when you say 'DJI still use barometer data converted to a nominal ASL height' that you might mean 'converted to an 'AGL height' as my understanding is that the initial barometric reference point is the ground level from which the drone initially departs. I'm a newbie just studying to write my licence exam, so am the first to admit my knowledge is probably not as advanced as yours on this topic. Thanx in advance for any response for clarification.

djiuser_q0aPIJivn2ld Posted at 2-17 12:24
Good info, captain. I'm wondering if, when you say 'DJI still use barometer data converted to a nominal ASL height' that you might mean 'converted to an 'AGL height' as my understanding is that the initial barometric reference point is the ground level from which the drone initially departs. I'm a newbie just studying to write my licence exam, so am the first to admit my knowledge is probably not as advanced as yours on this topic. Thanx in advance for any response for clarification.

I'm wondering if, when you say 'DJI still use barometer data converted to a nominal ASL height' that you might mean 'converted to an 'AGL height'
No .. I said ASL because I meant ASL.

I was talking about one of the two different heights that is shown in image metadata.
One is Relative Height - the same height you see on the screen when flying and the other is labelled GPS Height (or Absolute Height).
It does not come from GPS, but is derived from barometer height and a calculation based an an assumed standard air pressure.
This number is often quite inaccurate.

The height you see on the screen is height above the level of the launch point.

Here is an example of the two different heights shown in image metadata.
The launch point was about 5 metres above sea level.

Mavik mini has been great but now getting all of the charging lights
Blinking three times while in the charger. Is there an error that is signified by three flashes then paused while in the charger?
When I take it off the charger, and push the on button, no lights come on.
I can’t figure out what to do next.  

djiuser_LJfNZdmOdpjz Posted at 2-17 17:43
Mavik mini has been great but now getting all of the charging lights
Blinking three times while in the charger. Is there an error that is signified by three flashes then paused while in the charger?
When I take it off the charger, and push the on button, no lights come on.

Please don't post a completely different subject in an existing thread.  Start a new topic.

Name Calling someone who is offering valid Education is not Trolling.
It is not even close to Trolling.
Plus their post was helpful to me - directly related to the original question.

OTOH your Name Calling is against most forum rules.

Hypocrisy is not an inaccurate term for your name calliing

hallmark007 - perhaps you should take a break and go have a nice fly
until you can interact reasonably.

I have to say despite the minor nastiness between trolls and leprechauns I found this thread to be very educating.  I have learned there is a very big difference between triangulation and trilateration.
I don;'t think this info is beyond anyone's understanding if they are willing to do the research. Here is a great article explaining the difference between  triangulation, trilateration nad true-range multilateration:

Triangulation vs Trilateration vs True-range multilateration

By understanding these methodologies including the the benefits and weaknesses of each will make you a better pilot and a better navigator.