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Bad wobble in active track chasing a boat

Gbower

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I'm trying to use active track on my Air 2s to follow some boats and I'm getting a serious wobble from left to right so I stop the active track as it just feels like it's going unstable. I did a refresh DJI Assistant and no change. Everything is up to date. I'm using the RC Pro controller. I tried tracking me and a car and no problem so far. The boats were all moving when I locked on them and it recognizes them as a boat. I haven't used active track to follow boats before but thought it would be worth trying. WRONG. I can live with just tracking them manually which isn't a problem but it's supposed to work. Any help would be appreciated. I'll try to do up a short video of it going side to side.
 
The boat is a small object in the frame and likely it’s struggling to keep it tracked. Have you tried getting much closer?
This. It's a much smaller object relative to the frame size, so it's harder to track. In the case of this particular video if you wish to keep that frame it may be more beneficial to track the boat+wake instead of just the boat, as the wake will generally be somewhat consistent as the boat keeps steady and would be a larger subject to track.

If it was a different kind of framing, such as knowing the boat was going to pass a dock or lighthouse, you could set a POI or track a stationary object that the boat would be going past as you circled around. It would create the illusion of tracking the boat seamlessly but you're actually just staying fixed on a landmark it passes by.
 
Tested again this morning and wasn't very far from a sailboat and as soon as I started active track it started going back and forth so immediately aborted and then tried POI which worked perfectly. Here's a screen capture of part of the flight. I also removed the ND filter as someone suggested and was a lot closer than my previous flight.
 
Still seems like a very small sample area you're selecting, Should grab a bigger box that includes the mast.
I was further away when I did the POI and had no problem so I don't think that is the problem. I was only 70' above the water and about 100' away from the sailboat. It easily identified it as a boat.
 
I was further away when I did the POI and had no problem so I don't think that is the problem. I was only 70' above the water and about 100' away from the sailboat. It easily identified it as a boat.
Only other thing I can think of is that POI is usually set in buildings and structures. Active track is usually expecting a person.
 
Only other thing I can think of is that POI is usually set in buildings and structures. Active track is usually expecting a person.
The active track is designed to track either a person, a car or a boat. It identifies what it is tracking. POI or Spotlight can pick up just an object.
 
It’s hard to say what characteristics DJI use in their algorithm to identify an object such as a boat but a rear shot from a distance and height does not make recognition easy. Sideways on would be far easier. Potentially the wake behind the boat would assist and give a direction to follow but the boat itself would just appear as a small rectangle.

POI can use contrast, sharpness, colour and brightness to identify the point of interest and quite easily allow a circular orbit around the object. It is, however, expecting a static object. In your case the slow speed of the boat must be within its limits to track as a POI.
 
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It’s hard to say what characteristics DJI use in their algorithm to identify and object as a boat but a rear shot from a distance and height does not make recognition easy. Sideways on would be far easier. Potentially the wake behind the boat would assist and give a direction to follow but the boat itself would just appear as a small rectangle.

POI can use contrast, sharpness, colour and brightness to identify the point of interest and quite easily allow a circular orbit around the object. It is, however, expecting a static object. In your case the slow spread of the boat must be within its limits to track as a POI.
Later in the week if I get a chance I'm going to catch someone launching and try tracking them from a standstill and really close if they'll let me do it. There's a boat launch where I launch so should be possible. The good thing is all of my tracking in the past has been manual but just wanted to try this and now want to find out why it won't follow properly. It's easy to track them manually and a lot of fun. Thanks for your comments.
 
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I recalibrated the gimbal and everything I could and tried the active track again this afternoon on a couple of power boats and it seemed to work perfect. Still need to test again with a sailboat. The sailboat under motor power is still much slower than the second boat I caught today and the ones I've done were much closer too. Here's a short video of today's flight.
 
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I recalibrated the gimbal and everything I could and tried the active track again this afternoon on a couple of power boats and it seemed to work perfect. Still need to test again with a sailboat. The sailboat under motor power is still much slower than the second boat I caught today and the ones I've done were much closer too. Here's a short video of today's flight.
Yes, much better and the boat shape is more defined from the start and very bright against the background so good contrast to aid tracking.
 
Been doing a bit more testing and thought I was rid of the wobble but it's still there. For a while I thought it was only on sailboats but have now had it wobble on power boats too. I had one where I started out with the boat stopped and followed him for about 3000' and up to 25mph and rock solid and left him and tried tracking a sailboat with wild wobble. While following the sailboat I stopped active track trace and went to parallel and also POI and both of those were solid. I've since done a number of spotlight and parallel tracking with no problems so when I get a chance I'm going to try getting in really close to a sailboat and try again. I'm actually quite happy with either parallel following or POI as they both look pretty neat and better than being behind the boats.
 
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