always calibrating

[Hermz]

Hi Guys

So I am very new to the drone owners world, and I am very much
learning everyday. To most this will seem like an stupid question but I need to know for sure. The thing is I work on a yacht and we travel a lot so what I need to know is do I have to calibrate my drone every time I start it up in a new aria? Some guys say I should and others say I should not. I hope to get a yes definitely do or no do not do it. And why I should or should not. I am asking on this forum cos most of the guys here do not have much experience with drones themselves so I need to hear from people with more knowledge.

Thanx in advance

 

[Top Hat]

ONLY WHEN IT PROMPTED YOU TO CALIBRATE!!!!
I have 1 instance that after I fired up the MP, I got prompted by a WARNING,
"Magnetic Interference/Calibrate Compass or move to different location", I just moved the MP a few feet and the warning was gone and I was off flying.

 

[james_mav]

Hi Guys

So I am very new to the drone owners world, and I am very much
learning everyday. To most this will seem like an stupid question but I need to know for sure. The thing is I work on a yacht and we travel a lot so what I need to know is do I have to calibrate my drone every time I start it up in a new aria? Some guys say I should and others say I should not. I hope to get a yes definitely do or no do not do it. And why I should or should not. I am asking on this forum cos most of the guys here do not have much experience with drones themselves so I need to hear from people with more knowledge.

Thanx in advance

Most of the problems reported on this board due to calibrating are from those doing too much calibrating instead of not often enough. If the drone gives you a warning that it needs calibrating then do so otherwise I'd leave it alone.

 

[Robert Mitchell]

Like the above posters say, it seems the Mavic is designed not to need continual calibrating.

If it needs it, it will tell you, otherwise let it be.

That said, if you see the need, don't hesitate and do it right.

 

[Hermz]

Thanx for the info guys. Will definitely follow the advise you gave me.

 

[PaoloOne]

Even if not required it is a good rule to calibrate every time you move more than 100 km away from where you have previously calibrated, especially if you move perpendicularly across the magnetic declination lines.
Magnetic declination - Wikipedia

 

[PaoloOne]

Like the above posters say, it seems the Mavic is designed not to need continual calibrating.

If it needs it, it will tell you, otherwise let it be.

That said, if you see the need, don't hesitate and do it right.

There is not such thing, the Mavic has no knowledge of the world magnetic field declination based on the location. It can only detect discrepancies in the readings of the two compasses, in that case will warn you but is not able to tell if you have moved in a location with a different declination. For this cases the only reliable instrument you have is your brain and the common sense of recalibrate.

 

[PaoloOne]

This map explains why you need to calibrate, for example if you fly from New York to San Francisco your compass will be off about 20°, the Mavic will not be able to detect that as both the compasses can give good readings yet they will need to be adjusted to the new declination.

 

[Robert Mitchell]

This map explains why you need to calibrate, for example if you fly from New York to San Francisco your compass will be off about 20°, the Mavic will not be able to detect that as both the compasses can give good readings yet they will need to be adjusted to the new declination.
View attachment 18610

So, China has the exact same declination as NC, and every other location within 1000 miles of my home? Because I have never calibrated and it has always been spot on

 

[PaoloOne]

Yes, you can be lucky but sometimes people don't realize that the compass is off until they activate a RTH procedure because in that case the FC is having problems when sets the heading in one direction and the GPS is showing that has moved to another. When you fly manually instead you may not notice a tiny divergent angle. Long story short, if you calibrate only when the Mavic tells you may end up realizing that a calibration was needed when is too late.

 

[PaoloOne]

So, China has the exact same declination as NC, and every other location within 1000 miles of my home? Because I have never calibrated and it has always been spot on

Plus the 1000 miles may be valid with two conditions :
1) you moved parallel to the magnetic field
2) there are no local distortions of the magnetic field

 

[Robert Mitchell]

Plus the 1000 miles may be valid with two conditions :
1) you moved parallel to the magnetic field
2) there are no local distortions of the magnetic field

Ok, I'm not disputing you, but I have experienced no deviation based on the following:

I always do a heading check at a new location. I check my heading against that indicated on the map. Admittedly I would have missed a degree or two, using a quick visual assessment.

I have done RTH checks and they were always successful.

Again, not disputing you but why does DJI not make it clear that calibrations are essential for the Mavic at different locations, if they were? Page 50 in the user manual "calibrating the compass" makes no mention of need to calibrate based on location. Or did I miss that somewhere else in the manual?

Are you sure that the Mavic doesn't use newer technology to automatically compensate, as it does have precise knowledge of your current location?

It would be easy to program automatic compensation for a database of deviations.

If you know all of this to be incorrect, I stand corrected, and am indeed lucky.

All said I still believe excessive calibration causes more problems than it solves in the case of the Mavic.

 

[BigDuke6ixx]

All said I still believe excessive calibration causes more problems than it solves in the case of the Mavic.

Based on what evidence?

 

[benjaminkan]

It could be that every time you calibrate a device, and save the settings, it may deviate from the "true value". I deal with scientific research machines and devices which cost at least 30x the mavic and this is one issue we face with constant calibration. That once "calibrated" it overwrites the previous calibration file. So if the new calibration was done incorrectly, and we save it, now we have deviated from what it's true value is meant to be. The more times this error occurs, the values would already be completely destroyed and would have deviated from what it is meant to be. Haha hope that makes sense

 

[BigDuke6ixx]

It could be that every time you calibrate a device, and save the settings, it may deviate from the "true value". I deal with scientific research machines and devices which cost at least 30x the mavic and this is one issue we face with constant calibration. That once "calibrated" it overwrites the previous calibration file. So if the new calibration was done incorrectly, and we save it, now we have deviated from what it's true value is meant to be. The more times this error occurs, the values would already be completely destroyed and would have deviated from what it is meant to be. Haha hope that makes sense

Yeah, but what about convergence towards the mean?

 

[Robert Mitchell]

Based on what evidence?

Let me rephrase. I believe it has the potential to cause more problems based on DJI s lack of emphasis on the procedure, combined with the multiple testimonies of people who have never, combined with the almost certain negative results of a bad calibration.

 

[benjaminkan]

Yeah, but what about convergence towards the mean?

If there is error calibration and it deviates farther from the true value, your mean value would have definitely drifted away from what the true value would actually be. So is it calibrated? Yes but is the calibration out of whack? Yes. That's why dji should come up with something like a validation sequence which requires you to have maybe 50 calibrations at a go in order to get, as you have mentioned a convergence towards the true mean.

 

[BudWalker]

Even if not required it is a good rule to calibrate every time you move more than 100 km away from where you have previously calibrated, especially if you move perpendicularly across the magnetic declination lines.
Magnetic declination - Wikipedia

The compass calibration does not determine the geomagnetic declination. In fact, it can not determine the geomagnetic declination. If it were determined during the compass calibration then a required step would be to precisely point the AC true north and then tell the AC. In effect, you'd have to tell the AC what the declination is.

The geomagnetic declination is determined from the GPS coordinates.

 

[mikeGR]

This topic has been discussed numerous times before. Why don't you people do some search in the forum and find the answers you need before starting a new thread?

As for the above posters, I'm traveling thousands of miles across the globe frequently and have always flown with no issues, despite never calibrating once and using both manual and RTH or intelligent flight modes. This is enough evidence for me to believe that the Mavic does not need a fresh calibration unless genuinely prompted.

 

[ErikDF]

I have never calibrated my Mavic and have flown it in different places in Canada and Sweden without problems. I allways do deliberate RTH flights.