Today, I was on a hill, which was about 100 feet higher than the surrounding area. I wanted to track a sailboat which was on the water below me. I decended down to about 35 feet above the water and initiated the ActiveTrack mode. I drew a box around the sailboat and pressed Go. The DJI Go app told me the altitude was too low. The altitude display read something like -65 feet. So, I gather from this, that you cannot use ActiveTrack when something is below your take off altitude? That seems like a pretty severe limitation. Are there any ways around this?

unfortunately active track is a bit stupid with certain things.  they really need to update it and fix some issues.    its sluggish to pick up speed and is easily confused moment it breaks visual.. the inspire series of active tracking is smarter and uses logic like following around corner and regaining lock and following.. mavic just gives up

The altitude which displays on the app is the relative altitude to the takeoff point, and one of the requirements for activating Active Track is to keep the drone at least 2 meters above, so you can't initiate it when the relative altitude is lower than 2 meters. If you want to use this function, you can first land the drone at that lower point if possible, stop the propellers, and then take off again, the relative altitude will count positively. But I suggest using it very carefully, because it is not easy to predict the environment at that time, especially when it is beyond visual range.

DJI Thor Posted at 2017-9-4 18:25
The altitude which displays on the app is the relative altitude to the takeoff point, and one of the requirements for activating Active Track is to keep the drone at least 2 meters above, so you can't initiate it when the relative altitude is lower than 2 meters. If you want to use this function, you can first land the drone at that lower point if possible, stop the propellers, and then take off again, the relative altitude will count positively. But I suggest using it very carefully, because it is not easy to predict the environment at that time, especially when it is beyond visual range.

I think it makes more sense for your engineers to overcome this silly obstacle.

DJI Thor Posted at 2017-9-4 18:25
The altitude which displays on the app is the relative altitude to the takeoff point, and one of the requirements for activating Active Track is to keep the drone at least 2 meters above, so you can't initiate it when the relative altitude is lower than 2 meters. If you want to use this function, you can first land the drone at that lower point if possible, stop the propellers, and then take off again, the relative altitude will count positively. But I suggest using it very carefully, because it is not easy to predict the environment at that time, especially when it is beyond visual range.

so if we are on top a large hill, we should land on the water then take off again when chasing a boat in active track mode?

ImHereToCrash Posted at 2017-9-4 20:44
so if we are on top a large hill, we should land on the water then take off again when chasing a boat in active track mode?

That was going to be my exact comment! LOL. Hardly practical at all!.
Why not use the Mavic Pro's *true* altitude, not its relative altitude form the takeoff point?
Why not let the user decide if it's ok to fly at the altitude selected for ActiveTrack?

There are so many ways to solve this limitation... but landing in the water is not one of them!

Jyunte Posted at 2017-9-4 21:09
That was going to be my exact comment! LOL. Hardly practical at all!.
Why not use the Mavic Pro's *true* altitude, not its relative altitude form the takeoff point?
Why not let the user decide if it's ok to fly at the altitude selected for ActiveTrack?

i agree..  the thing bothers me is the mavic is labeled as a pro device.  a pro device should allow more user intervention and manual take over..    i understand the logic maybe the mavic pro doesnt know where ground is in realtion to where it is once off the hill and hovering over the water because its out of range of ultrasonic and vps, but again we should be able to set custom height if we know its clear..

the thing is, i understand DJi is being cautious but i and many others dont need Dji to be a overly strict nanny about things either.  i would really like it if certain features could be overridden in some ways without totally breaking the features.  active track doe not need to know where ground is, in my experience active track is very blind to where the ground is once its activated... at my farm i had ti following my atv and it nearly crashed into the hill i climbed.. so i dont understand the logic  used why it cant hover at a custom high from a different take off point..  specially if dji isnt utilizing data of where the ground is... they advertise it like it does but in reality, i always had to jump in and save it because it would have just flown into the hill not climb it.. where ios the middle ground DJI.. why do you make us fly 2 meters up from take off location but then proceed to ignore active distance from the ground there after? wat is the logic?

ImHereToCrash Posted at 2017-9-4 20:44
so if we are on top a large hill, we should land on the water then take off again when chasing a boat in active track mode?

I just thought that I had added a phrase "if possible", and was just a "solution" at the moment, anyway. So if the drone is above the water then it is impossible.

Jyunte Posted at 2017-9-4 21:09
That was going to be my exact comment! LOL. Hardly practical at all!.
Why not use the Mavic Pro's *true* altitude, not its relative altitude form the takeoff point?
Why not let the user decide if it's ok to fly at the altitude selected for ActiveTrack?

I will forward this need to our engineers. Hope we can support it, appreciate your feedback.

DJI Thor Posted at 2017-9-5 02:31
I just thought that I had added a phrase "if possible", and was just a "solution" at the moment, anyway. So if the drone is above the water then it is impossible.

This is the first time I sense sarcasm in one of your responses.  Congratulations, you are human.  Keep it up.  

DJI Thor Posted at 2017-9-5 02:32
I will forward this need to our engineers. Hope we can support it, appreciate your feedback.

That would be great. All it really needs to do, in this situation, is display a pop-up with an OK and CANCEL option, stating that the current flight altitude is lower than the takeoff altitude, and that the Mavic will be unable to accurately report its correct altitude. Maybe it should also suggest carefully monitoring the visual sensors to make sure you don't fly it into the ground/water! Then it's up to the pilot to choose what to do next.