Mavic Air - drifting about!

Hi all.
Yesterday I went to try and get a burst of shots to try out a stacking technique in Affinity Photo. Put the MA up in the woods, about 20 feet over a river, to do some shots of a weir. To my surprise, it started drifting about, maybe a foot or two side to side, and backwards. Usually it is nailed to the sky and rock solid. I was hoping to get 49 burst shots (7 x 7) but it just wasn’t steady enough and I didn’t dare take my eyes off it for too long because of overhanging branches. I tried turning the obstacle avoidance off in case it was the water fooling the downward sensors but no change. I haven’t tried again today as its been pouring with rain all day. Any advice?
Here’s the picture, which sort of smoothed the water with 7 shots, but 49 would be much better.

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My guess would be “wet trees”. These can have quite an impact on GPS accuracy.
The ones needed for most accurate positioning are the lower satellites, not the overhead ones so much and, judging from that pic, these would be “behind” the trees.

Did you check how many satellites were locked when it was wandering?

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Nice pic tho! Like how the stack accentuates the static waves in the water tumbling over the weirs.

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Oh dear, I never thought to do that. I will go and do it again in the next day or two and check satellites. Thanks for that.

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If you have a GPS app on your phone that shows the number and location of available satellites, that can be useful info.

Also - fly your MA above the trees and see how many satellites, and compare with when in position for the photo and see how many have been lost. These will all be low ones.

Thanks. The stacking works really well. Unfortunately, although the MA does a burst of 7 really quickly, it takes a few seconds to write them to the card. I will also have to check if its quicker storing in internal memory, probably is. You really need about 50 shots to get that creamy water effect you get with a long exposure. The beauty is you can use a high shutter speed to do it.

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Won’t they be high ones, because you can only see the sky directly above?

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You can check the overall distribution of satellites on the phone when you’re in more open space and compare.

Sorry, I misunderstood, you mean that the lost ones will all be low. Yes, that makes a lot of sense and the angles mean that a lateral fix is more difficult.

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I’ve been trekking in wet woodland and my phone GPS was as useful as a chocolate teapot. LOL

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Hi I’m new to this but I have been listening to a lot of you tube videos. Apparently the Mavic Air was struggling with hovering and drifting. The result was a firm ware upgrade whic adjusted the PID control of the drone. I learnt this of a you tuber called 51 Drones.

Thanks Rich. I will check that out, although I thought I was running the latest firmware on Air and controller.

I’d suggest that if this only happened while you were over the water it could simply be the downward VPS was unable to get a decent lock?

I don’t know what the angle / field of vision is on the Air VPS system but at that low a height over water, it might just be that mate :slight_smile:

Thanks Spike, I will try and isolate the cause next time I’m out. It was a bit unnerving though!
Cheers

The reason I suggested that as a possible cause is because I’ve got some of that artificial grass malarky in my garden.

On the rare occasion I take off from my garden (which I can probably count on one hand), the Mavic Pro bobs and sways around in the air like there’s a 50mph wind going on!

First thoughts when seeing it do this?!

“Oh shit! What’s wrong!??!!”

Second thought?

“Ah, it can’t lock on to my weird grass pattern :blush:

You never know… :+1:

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That makes sense actually.

A combination of poor GPS signal as @OzoneVibe pointed out, combined with VPS having nothing to lock on to definitely wouldn’t provide a stable hover.