X7 Judder/Stutter - HELP!

[Eagle33331]

Folks, I cannot get a smooth pan/drift/follow etc. either by camera movements or drone movements, on my X7. My dealer has been testing it and I've included a link to their test clips. It's unusable and the previous X5S on my Inspire 2 didn't suffer this issue.

They've tested with my camera and theirs, on my I2 and got the same result. The issue appears on both SD and SSD. Which suggests an issue with the image transfer line in my drone? I've asked them to test my camera on their I2.

You can see an example clip here: Stutter Clip Has anyone here suffered similar and do you agree that the stutter is not normal? (The big jumps may be down to poor finger work; it's the many micro stutters and occasional smaller jump that I experience..)

Now is a really bad time to not be able to work so thanks in advance for any support. I'm tearing my hair out.

 

[Donnie Frank]

Folks, I cannot get a smooth pan/drift/follow etc. either by camera movements or drone movements, on my X7. My dealer has been testing it and I've included a link to their test clips. It's unusable and the previous X5S on my Inspire 2 didn't suffer this issue.

They've tested with my camera and theirs, on my I2 and got the same result. The issue appears on both SD and SSD. Which suggests an issue with the image transfer line in my drone? I've asked them to test my camera on their I2.

You can see the clips here (I'll try to work out how to embed them, here, meantime..) Has anyone here suffered similar and do you agree that the stutter is not normal?

Now is a really bad time to not be able to work so thanks in advance for any support. I'm tearing my hair out. Ian

Hard to tell if it's mechanical or digital judder. For further troubleshooting, I suggest 2 things:

1) Yaw the drone as opposed to panning the camera. Do this either manually or in flight. This will either eliminate or put the blame squarely on the gimbal.

2) Do this same test in low light conditions. i.e. At night. Make sure your exposure (E.V.) is in the slight negative. Like -0.3ev, for example. If the judder goes away under these conditions, it's digital.

We have to better understand the problem before we seek out solutions.

D

 

[Donnie Frank]

Never to be heard from again....

 

[AAP]

It’s hard to determine what he is referring to especially because he is doing bench test.
What are your gimbal settings?

 

[Eagle33331]

Sorry folks, my partner's daughter just had emergency brain surgery which required my partner to fly UK to Australia and she's struggling, rather. She's had to set up a Just Giving page to raise funds to cover some of the med x's. As a result I've had to park this until now.

Bench test is best for this issue because it allows total control and removal of some other potential causes e.g. flight vibration.

Donny, can you explain the thinking behind your 2)?

The gimbal movement is totally smooth. It's not a mechanical issue. Also the dealers gimbal/camera gives same result. Filming in a yaw rather than a gimbal pan gives same result. So, per above, this suggests the issue is with the I2's electronics in the digital signal domain*? (It's not the card because same issue occurs on different card and it appears on both SD and SSD). Gimbal settings are normal.

So this issue is either representative of normal X7 recording (which the dealer is suggesting) or above* or I'm missing something. Fps is 25 and shutter 50th. The tester got the aperture wrong - over exposed - but this isn't relevant anyway. If this is 'normal' then it's of no use to me and I wish l'd never sold my X5S.

Do either of you own the X7?

 

[AAP]

Yes I own th x7 for some time. The only time I notice jag is in the live feed sometimes but not in the raw footage. Also, I barely see what you are talking about. Have you tried the cam in The air yet? Also your moving the gimbal pan very slowly. What are your gimbal settings? I ask because you may need to add expo so you can get that buttery smooth operation. To be continued

 

[Eagle33331]

Yes I own th x7 for some time. The only time I notice jag is in the live feed sometimes but not in the raw footage. Also, I barely see what you are talking about. Have you tried the cam in The air yet? Also your moving the gimbal pan very slowly. What are your gimbal settings? I ask because you may need to add expo so you can get that buttery smooth operation. To be continued

That clip was recorded by my dealer - the drone's with them right now. Yes same issue in the air. I'm a professional photographer/videographer and can make a super smooth pan without any mechanical stuttering. The gimbal settings were set for cinematic smoothness including at stop. I'll find another clip that is more clearly illustrative. Many thanks.

 

[psionic001]

I would reinstall the latest firmware on the drone and controller as a minimum. Can you see (or hear) the gimbal micro stuttering? Have you tried the other remote controller or temporarily swapped stick assignment (make the up down do the gimbal pan). That should rule out any radio control issues and focus the issue on electronic failure.
Also reset all software gimbal settings in the Go4 app.
If it were me, my next step would then be to remove the whole flight control (cinecore) module and remove and reinsert all connectors. Takes a bit of careful patience but you can do it yourself if you are that way inclined.
Hope you can track this down.

 

[Eagle33331]

I would reinstall the latest firmware on the drone and controller as a minimum. Can you see (or hear) the gimbal micro stuttering? Have you tried the other remote controller or temporarily swapped stick assignment (make the up down do the gimbal pan). That should rule out any radio control issues and focus the issue on electronic failure.
Also reset all software gimbal settings in the Go4 app.
If it were me, my next step would then be to remove the whole flight control (cinecore) module and remove and reinsert all connectors. Takes a bit of careful patience but you can do it yourself if you are that way inclined.
Hope you can track this down.

Thanks for the comments. Visually, gimbal panning in both planes is completely smooth. I don't believe it's a mechanical/RC issue. The dealer is using my I2/X7 using his own controller, so I don't think it's controller. Re-installing I2 firmware is a good thought as is the Cinecore idea. I'll mention these to dealer. Thanks again - me too.

 

[niki]

The video is shot at 25fps and because of that the best experience is to play it on a screen with 50Hz or 100Hz refresh rate, most desktop computers run on 60hz and such a video will have some stutter playing on them. I can tell that when I change my screen refresh rate to 50Hz your video plays a bit smoother.

What took my attention is looking at the ground just in front of the lens, while panning the ground shakes left to right almost looking like jello effect, but this actually shows that the camera is shaking sideways while panning which in my opinion is the problem. There is some wind that can alco contribute to the shaking as the X7 is bigger profile and more affected by wind so maybe will be best to test in windless conditions. Do the motors run during the test? If they are then it's normal to have that shake which will not be visible in most cases while in the air until you have something extremelly close to the camera like the ground is in this test. If the motors do not run, then there could be a cooling fan in the inspire that causes vibrations or other mechanical or electronic problem inside the gimbal or gimbal dampening system. If possible ask your dealer to test your drone on the same place/framing using X5S camera to compare the results.

 

[Eagle33331]

Thanks Niki. I shoot 25/50/100 fps for Euro' PAL video standard.

There was wind in the test but I get the same stutter even indoors; so it's not a wind issue. Rotors off, solid kitchen table, no fan noise. It's not mechanical that I can ascertain. It happens on both my and the dealer's camera/gimbal. I'm hoping the dealer will test my camera on his I2. That will, hopefully, tell us whether the issue is 'normal behaviour' or not.

I'll post another clip where the stutter is a bit more obvious but am en route to airport just now. So, as soon as I can..

Many thanks.

 

[Eagle33331]

Here's a clip of my X7 shooting on dealer's I2. The stutteryness is still there. The conclusion is that this is normal for the X7:

 

[Eagle33331]

Ok, so I bought an X5S to try - same issue. Refreshed f/ware. No change. But, just discovered footage is almost completely smooth in the NTSC setting. In PAL - needed for UK - it's awful and not what I experienced pre latest s/ware.

I am viewing on a 2018 Macbook Pro which has a 60hz refresh rate. But, the difference is so great I find it hard to believe that can be the issue. It's not frame rates/shutter either - I shot 30fps/60th NTSC and 25fps/50th PAL.

Has anyone got any bright ideas while I wait an eternity for DJI to advise?

Thanks.

 

[Donnie Frank]

Here's a clip of my X7 shooting on dealer's I2. The stutteryness is still there. The conclusion is that this is normal for the X7:

The thing is, I've seen this kind of jutter in Red cameras. I've seen this kind of jutter make it into major motion pictures. My personal experience with it is that is more prevalent in bright, Sunny conditions. The jutter seems to disappear @ night. It doesn't seem to have anything to do with shutter speed. Invoking the 180° rule doesn't fix it. I don't shoot faster than 30FPS, so I don't know if higher frame rates fix it, but I don't think it does.

Every time I see a thread like this I always make the same suggestion; Try the same shot at night. Try the same shot under the same lighting conditions with another camera. Once you see the consistency of this anomaly, you might be able to conclude that there's nothing wrong with your camera.

Note: Different cameras may require slightly different environmental conditions to suffer from the jutter anomaly. But rest assured, there's a "sour spot" where they all have jutter issues.

D

 

[Eagle33331]

Thanks for the thoughts, Donnie. I don't accept that this is par for the course. Both X7 and X5S are behaving in the same way - so it's not the camera. It's not right that it should be ok in NTSC and unusable in PAL.

Check out these links to two clips I've dropped onto YT. One labelled NTSC and one labelled PAL. View in 1080. They make the issue much clearer than above. You'll see the NTSC footage is smooth; the PAL footage is jerky and unusable. Something is plain not right.

https://youtu.be/LoJA7n4iT08 PAL CLIP
https://youtu.be/KQ4KmnsMoPo NTSC CLIP

I'll try a similar test with my Mavic 3 Cine. If it's smooth in PAL, I'd say that's pretty conclusive there's an issue somewhere in the I2.

Cheers.

 

[AAP]

Hi. I’m going to test with mine today. I’ll try to find a processing issue. What frame rates were you using? H264 or h265? I’ve always had a jitter with h265 and Omer computers. I’ll try to repeat and let you know.

 

[Eagle33331]

Hi. I’m going to test with mine today. I’ll try to find a processing issue. What frame rates were you using? H264 or h265? I’ve always had a jitter with h265 and Omer computers. I’ll try to repeat and let you know.

Thanks, AAP. I used H264 to make things easy; frame rates as above - 25 and 30; shutter 180 degrees. If my issue was a common problem, I'd have thought the forums would be awash with it. But let's see..

 

[Donnie Frank]

Sorry folks, my partner's daughter just had emergency brain surgery which required my partner to fly UK to Australia and she's struggling, rather. She's had to set up a Just Giving page to raise funds to cover some of the med x's. As a result I've had to park this until now.

I hope your friend's daughter gets better.

Bench test is best for this issue because it allows total control and removal of some other potential causes e.g. flight vibration.

Yep.

Donny, can you explain the thinking behind your 2)?

Check out my subsequent reply below. As I said, I've seen jutter from Red cameras in full feature production. It's an anomaly that exists and under certain conditions, no amount of adjustment can fix it. If I recall, even a strong ND filter (4 stops) didn't fix it.

The gimbal movement is totally smooth. It's not a mechanical issue. Also the dealers gimbal/camera gives same result.

As I suggested, try shooting at night. Dollars to doughnuts the problem goes away.

Filming in a yaw rather than a gimbal pan gives same result. So, per above, this suggests the issue is with the I2's electronics in the digital signal domain*? (It's not the card because same issue occurs on different card and it appears on both SD and SSD). Gimbal settings are normal.

It's not the card or the SSD.

So this issue is either representative of normal X7 recording (which the dealer is suggesting) or above* or I'm missing something.

I'll take it a step further. This is normal for ALL cameras. As I said, I've seen Red cameras suffer from jutter in full feature production.

I was watching a well-budgeted full feature film a few months ago (can't remember which one). The camera tilted up to show a sky scraper. There was massive jutter in this shot. After years of studying this anomaly, the only "cure" is to pan slower or work in darker conditions (like night time).

Fps is 25 and shutter 50th. The tester got the aperture wrong - over exposed - but this isn't relevant anyway. If this is 'normal' then it's of no use to me and I wish l'd never sold my X5S.

Do either of you own the X7?

I have an X5 and an X3 along with a myriad of drones and cameras. My Canon 70D does the same thing. The tighter the FOV, the worse the jutter becomes.

D

 

[Donnie Frank]

Thanks for the thoughts, Donnie. I don't accept that this is par for the course. Both X7 and X5S are behaving in the same way - so it's not the camera. It's not right that it should be ok in NTSC and unusable in PAL.

Okay...this is the first I've heard that you were shooting in PAL. I thought PAL and NTSC were transmission protocols, with the main difference being the refresh rates. US 60Hz electrical frequency vs. everywhere else 50Hz electrical frequency. Since you're going from your storage media directly to your Mac (and not transmitting), it seems it would be easy to simply slow down the NTSC recording to 24FPS to more closely match the PAL 25FPS.

I checked your original post and subsequent posts. PAL wasn't even brought up until this morning. That said...

I have zero experience with PAL. I would suggest trying your pans @ NTSC 24FPS, which is closer to PAL's frequency. Troubleshooting is all about eliminating the obvious first, and then moving down the line to more esoteric solutions. Looks like you're on the right track by borrowing similar cameras, but based on your posts, I can't tell if the issue is due to PAL specifically or simply because PAL is a slower frame rate.

Check out these links to two clips I've dropped onto YT. One labelled NTSC and one labelled PAL. View in 1080. They make the issue much clearer than above. You'll see the NTSC footage is smooth; the PAL footage is jerky and unusable. Something is plain not right.

https://youtu.be/LoJA7n4iT08 PAL CLIP
https://youtu.be/KQ4KmnsMoPo NTSC CLIP

I'll try a similar test with my Mavic 3 Cine. If it's smooth in PAL, I'd say that's pretty conclusive there's an issue somewhere in the I2.

I know the camera and bird have their own firmware. Unfortunately, DJI release notes are horrid. If you are absolutely convinced that this is an issue with the X7 (and no other contributing factors), I would try rolling back the camera firmware.

Personally, I think this has something to do with the sensor. I would compare MFT sensors to other cameras you own with MFT sensors. The X7 has an odd sensor size that is smaller than the MFT sensor in your X5 and X5S cameras. I'm tempted to blame the smaller sensor.

Sorry I can't be of more help.

Here are your exact symptoms in another camera running NTSC (advance to 00:01:15).

D

 

[Eagle33331]

Thanks for the time, effort and suggestions, Donnie. I think the fact that the issue is the same on both X5S and X7 rules out the camera. I have read that this kind of thing is not uncommon; but it's much worse than it was with my previous X5S pre-f/ware updates. I barely noticed it before; now footage is unusable. I just wouldn't output jittery footage in a pro' environment. I'll try replicating the pan with my Mavic 3 and see if it suffers same.