Mini 2 - what’s going on?

Its not that bad ;o)


I’d agree. You need to look closely … and don’t forget this is just one of many you’d use for a pano.

The shutter speed of 1/200th would generally be good but was this the same flight where you got the wobbly video? If so I guess it was windy? Looking closely across the frame I’d suspect camera shake being the probable cause of the softness?

fantastic; learn something every day at GADC!
here’s the link, I hope it works; oh, and thanks for taking the time to look at it, and the offer any advice.

that’s good to know; I’m new to this!

yes, it was the same flight as the wobbly video; it was windyish, but I think more so was the gusts that came through.
As I said, I was using an ND8CPL, (having lost my CPL) and so the shutter speed of 1/200, together with a drone fighting the gusts!
I’ve been out today trying a test to see if the ND8CPL is effective or not and found that with the filter the shutter speed was 1/125, whereas with no filter the sutter speed was 1/2000, which would obviously, give a sharper image from a hovering drone being buffeted by the wind!

1 Like

I’d do a test on a still day, or maybe even on the kitchen table.

The video looks all wrong even for a windy day .

1 Like

As you know ND8 is 3 stops (I’m assuming the PL is accounted for in the ND8 rating) which would equate to 1/1000th sec so on that basis the ND8 would appear to be closer to ND16 or 4 stops?

But I think you’re right - the gusty wind was introducing camera shake which has been exacerbated by losing 3, possibly 4, stops of light.

I noticed an issue at the beginning of the flight, pre take off, with some erratic movements from the camera, so I switched the drone off, and back on again, thinking that would sort it.
I have been looking through the files recorded on the SD card and not sure why, but the camera jitter got recorded? Here’s the clip?

That video 220512 (7).MP4, at the beginning and at the end, the jello effect doesn’t seem to exist and reaches it’s worst mid rotation… My guess would be vibration in the drone, maybe an imbalance in the props, exacerbated by the wind, dependant on the orientation of the drone… What mode were you in by the way… Strange how the jello isn’t there, before you start rotating the drone, gets worse mid rotation and the fades off as you come to a stop at the end… I’d be thoroughly checking al the props, making sure none are damaged in any way, making sure all the screws are tight. Maybe even replacing the lot, just remember the props come in balanced sets, for each corner… They must be replaced as pairs and you must never reuse the original screws… As I say, with the jello effect not present for a couple of seconds at the beginning of the rotation, it just seems obvious to me that it’s some sort of imbalance.

Anyway hope you solve it

1 Like

Thanks for your comments; the drone is nearly new, I was fortunate to get a replacement in April after a flyaway!
However, I will check all the props and screws.
I have had a few flights since and the issue seems to have gone, although not in as much wind!
Maybe a combination of factors?

Given the location, perhaps a wee bit of sand in one of the motors could cause that problem

I suspect that perhaps the still was taken while the drone was in motion.

It’s rather nice with a bit of processing!

Indeed, while many flyers will happily take their drone out in winds that are above the stated limits of the mini 2 and come back saying it appeared to handle them just fine. I would suggest that at he height you wee flying and being over water with no obstacles, like trees etc. The wind (especially the gusts) were far higher than you imagined. The fact that the replacement drone is new (or newer) than the one you lost, is no guarantee. Many of the so called NEW drones are in fact refurnished drones. Could easily have been in a particular orientation, the wind was just a bit too strong for the drone to handle, and the jello was a result of it fighting to hold position, while rotating… although I would have expected a strong wind warning. Now if you were getting such a warning, then I would say that was the major factor, IF NOT however, then it just seems more likely to be an imbalance or as others have said, possibly a sticky gimbal.

If you have flown since and not had the problem, then it’ll be very hard to diagnose

1 Like

This looks like rolling shutter to me. Have you got a good high speed memory card to record on? A slow memory card can cause / enhance the jello effect as the data can’t be written quick enough. This is probabily why the start is smooth and it gets worst as the card gets bogged down. A U3 or V30 card will be more than adequate for a drone. A good way to test this is to film the same footage in 1080p and see if the effect is still there. If its gone then your card isn’t writing quick enough to cope with 4k.

A general rule of thumb for shutter speed is to set your shutter speed at twice your frame rate, so 4k footage @ 30FPS should have a shutter speed of 1/60. ND filters should then be used to bring the exposure in line. Shutter speed is also a big contributor to rolling shutter, especially when motion is involved.

I hope these help and i’ve not doubled up on anyone elses advice.

Yes, all helps as I’m learning whether it is the issue or not :ok_hand:
I use a SanDisk Extreme Pro 128gb so that should be fine, got it from Amazon too, as I’ve been had with knockoffs before!
Yes, the whole thing of ND filters is a subject; I’ve got the Freewell filters, but as I like to do images and video, I find that the filters slow the shutter speed on the images so much that a hovering drone in the wind blurs the image!
I’ve tested it again today and the wobbly video hasn’t appeared :thinking: so hopefully, it was a combination of things and a one-off :crossed_fingers:

Have you added any after market accessories to your MINI-2?

No, only had a Freewell ND filter on, that’s all.

would be an aftermarket accessory…

and might not of been fitted correctly and interfering with the gimbal movement meaning it was stuck and couldn’t do its job efficiently. that would definitely give you jello as the gimbal being stuck it would pick up all the vibrations from the motors :+1:t2:

1 Like

Does your Mini always produce this effect or only in that place? The last thing I am is a technician but it looks hot there which might well affect the electronics and hovering won’t produce much of an cooling airflow over the circuit boards. The other possibility (I think) could be magnetic interferance - I’m fascinated to know where that was taken but military bases spring to mind and the powerful antennas they use.
If you get to the bottom of it I would be interested to know. Good luck!

Obviously, I can’t say for definite it was, or wasn’t, but I had done some lower level clips with the first battery and all was fine?

Generally the footage is perfect, I had no previous experience of this; it was fairly warm but even hovering there was a good breeze, so not sure if overheating is the cause.
I have used the drone since with no such issues?
It’s in the Canary Islands and there’s nothing I can think of that would give interference; you can hardly get a phone signal there!
I feel that there was either, a temporary software glitch that caused the jitter on take off and when hovering; or, the effect of the wind? But for me the issue is within the video clip rather than the camera.
Anyway, I’ve flown quite a few times since and had no issues, so hopefully, all is fine now :crossed_fingers:
But thanks for your consideration and suggestions; if someone can learn from it then it’s worth sharing the experience :+1:

1 Like