ND FILTERS & Micro-jitters

[crossroad]

Yesterday 11.01 on a sunny beautiful day, with winds at about 3km, I fly with Freewell ND FILTER 32 (SS 1/200, ISO 100, 4k, 24p).
VERY BEAUTIFUL VIDEOS !!!

Today 12.01. In the same place, again on a sunny day, but with winds of 15km, I do the same flights (= ND Filter 32, etc.)
BUT in all the videos I have micro-jitters and something like pixelation or jaggies !!! It's not smooth movement and jitter especially when the camera shows lines or letters.

Does the problem come from the filter in combination with higher winds or is there a problem with the gimbal?

The filter is installed after booting, as gimbal due to known problems does not start if the filter is pre-installed.

 

[Gipsz Jakab]

Yesterday 11.01 on a sunny beautiful day, with winds at about 3km, I fly with Freewell ND FILTER 32 (SS 1/200, ISO 100, 4k, 24p).
VERY BEAUTIFUL VIDEOS !!!

Today 12.01. In the same place, again on a sunny day, but with winds of 15km, I do the same flights (= ND Filter 32, etc.)
BUT in all the videos I have micro-jitters and something like pixelation or jaggies !!! It's not smooth movement and jitter especially when the camera shows lines or letters.

Does the problem come from the filter in combination with higher winds or is there a problem with the gimbal?

The filter is installed after booting, as gimbal due to known problems does not start if the filter is pre-installed.

Can we see a video of this?

 

[Gipsz Jakab]

Yesterday 11.01 on a sunny beautiful day, with winds at about 3km, I fly with Freewell ND FILTER 32 (SS 1/200, ISO 100, 4k, 24p).
VERY BEAUTIFUL VIDEOS !!!

Today 12.01. In the same place, again on a sunny day, but with winds of 15km, I do the same flights (= ND Filter 32, etc.)
BUT in all the videos I have micro-jitters and something like pixelation or jaggies !!! It's not smooth movement and jitter especially when the camera shows lines or letters.

Does the problem come from the filter in combination with higher winds or is there a problem with the gimbal?

The filter is installed after booting, as gimbal due to known problems does not start if the filter is pre-installed.

Since he didn't post a video, I can only guess what he thinks when he says micro jitter.
I think this is the same phenomenon that we have already discussed on another thread: Because of 2-axis gimbal (this is the case with DJI Spark as well), it is more precisely the result of electronic YAW stabilization.
When the drone rotates slightly, the image also moves on the sensor. Electronic stabilization follows the moving image and stabilizes it by shifting the reading area of the sensor.
So, micro jitter is the phenomenon where the image vndorls from one pixel to another while seemingly standing still.
This phenomenon is particularly noticeable at dusk and is also due to the artificial darkness of the ND filter ...

 

[crossroad]

I made a sort video :

I repeat it again.
Just the day before with exactly the same conditions (same filter etc) except for the wind, the videos from the same locations are no problem

 

[Gipsz Jakab]

I made a sort video :

I repeat it again.
Just the day before with exactly the same conditions (same filter etc) except for the wind, the videos from the same locations are no problem

Yes, I hit it! I thought about this phenomenon. This is the combined effect of gimbal electronic stabilization, wind, and little light.
If you believe him, check out the same on the DJI Spark (also 2 axis gimbal) forum:

Video jittering

Hi, I havnt flown my Spark for quite a while. So I took it out of the box, run all the updates and went out for a hike to film the nearest mountain peak. Seeing the footage at home I am quite shocked to see that strong jittering. I havnt experienced something like that before, whats going on...

forum.dji.com

 

[crossroad]

Yes, I hit it! I thought about this phenomenon. This is the combined effect of gimbal electronic stabilization, wind, and little light.
If you believe him, check out the same on the DJI Spark (also 2 axis gimbal) forum:

Video jittering

Hi, I havnt flown my Spark for quite a while. So I took it out of the box, run all the updates and went out for a hike to film the nearest mountain peak. Seeing the footage at home I am quite shocked to see that strong jittering. I havnt experienced something like that before, whats going on...

forum.dji.com

Now I'm in great confusion.
About the little light :
It was a beautiful very bright day.
With ND32 the shutter speeds were from 1/60 to 1/200 (ISO 100)
I think I was in auto mode.
About the wind :
The last flight operated by RTH for the first time deviated from the exact point 1.5 meter! Probably because of the wind.

And what is the conclusion?
Use ND filter or not?
Do I use it only in very good weather and not in wind?

 

[Gipsz Jakab]

Now I'm in great confusion.
About the little light :
It was a beautiful very bright day.
With ND32 the shutter speeds were from 1/60 to 1/200 (ISO 100)
I think I was in auto mode.
About the wind :
The last flight operated by RTH for the first time deviated from the exact point 1.5 meter! Probably because of the wind.

And what is the conclusion?
Use ND filter or not?
Do I use it only in very good weather and not in wind?

Yes this is the seed solution. Unfortunately, the real solution would be a 3-axis gimbal but this is not possible here.
Now that we know the reason, we need to experiment when this phenomenon does not occur.

 

[crossroad]

I have been involved in photography since 1987.
I'm still thinking in terms of photography, about using ND but the ones that apply to photography don't apply to drones.

I canceled my order for ND 64.

 

[Jagerbomb52]

Funny I have a full set of Freewell ND filters including the ND 1000 that they do not make anymore and I have never had this problem described by Gipsz Jakab. I use them a lot, mostly the ND 4 stays on most times. I am one of the lucky ones with my two Anafi's that I can start them with the filters on and the camera will calibrate just fine at start up. I just think that some camera servo motors are better then others.

Have you tried to recreate the problem? Could these glitches in your video have been cause from your video editor or perhaps a bad SD card? Just trying to look at all possibilities

 

[Gipsz Jakab]

Funny I have a full set of Freewell ND filters including the ND 1000 that they do not make anymore and I have never had this problem described by Gipsz Jakab. I use them a lot, mostly the ND 4 stays on most times. I am one of the lucky ones with my two Anafi's that I can start them with the filters on and the camera will calibrate just fine at start up. I just think that some camera servo motors are better then others.

Have you tried to recreate the problem? Could these glitches in your video have been cause from your video editor or perhaps a bad SD card? Just trying to look at all possibilities

This phenomenon is not always noticeable. I suspect that a combination of shutter speed, frame number and strong wind (sudden shots) can be noticed, especially if the lines on the subject are vertical. It's worth trying the 180 degree rule: 30fps to 60 shutter speeds, 24fps to 50 shutter speeds, and so on.
I also experienced micro jitters on my Spark, but they weren't distracting in good light (only seen when I was flying in the wind or suddenly in sport mode when braking)
If the time is right (now there is fog for days) then I will try Anafi with these times.

 

[crossroad]

Funny I have a full set of Freewell ND filters including the ND 1000 that they do not make anymore and I have never had this problem described by Gipsz Jakab. I use them a lot, mostly the ND 4 stays on most times. I am one of the lucky ones with my two Anafi's that I can start them with the filters on and the camera will calibrate just fine at start up. I just think that some camera servo motors are better then others.

Have you tried to recreate the problem? Could these glitches in your video have been cause from your video editor or perhaps a bad SD card? Just trying to look at all possibilities

I'm using Premiere 2020 (with the latest update) for video editing on a "beast" PC, so I don't think that's where the problem is.
The SD card is the SANDISK EXTREME PLUS 128GB.
Gipsz Jakab gives the most likely explanation to date. (wind + ND filter + 2 axis gimbal). That needs further investigation.

I prefer to think so, rather than assuming I have a gimbal malfunction.
I am not satisfied with the overall quality of the anafi. (more on this in another post)

 

[Jagerbomb52]

Keep us informed. It would be good to see if you can duplicate what happened. So I guess you will be busy testing instead of enjoying the Anafi. Hope you find a solution.

 

[Jagerbomb52]

Also you might want to look into the many Bug Report issues for Speed Issues in Premiere 2020

 

[crossroad]

Also you might want to look into the many Bug Report issues for Speed Issues in Premiere 2020

Thank you Agustine.
i have no problem with speed from Premiere 2020.
I have a very fast processor and I always use proxies for editing 4K videos.

I am worried because there is a problem with all the videos from that day. The most serious of the jitter is the focus problem if you notice it carefully

 

[Jagerbomb52]

Thank you Agustine.


I am worried because there is a problem with all the videos from that day. The most serious of the jitter is the focus problem if you notice it carefully

Oh I know I have seen your video and agree there is a problem. If we do not cover all the probably causes we could miss the obvious solution. I for one have never had this problem and I have had my Anafi's for two years come July of this year. I have noticed a blur in my video because of the 2 axis gimbal but not a jitter that you have. A blur is common with 2 axis gimbals but jitters is not or we would have many more posts about it and we do not.

 

[crossroad]

Keep us informed. It would be good to see if you can duplicate what happened. So I guess you will be busy testing instead of enjoying the Anafi. Hope you find a solution.

I enjoy the fun, not the endless exploration and moaning.
But there is a problem here and I hope this is due to my own mistakes and not to a manufacturing problem