通知
すべてクリア

Roadbike Cycling


cincity
(@cincity)
Eminent Member
結合: 2年前
投稿: 45
Topic starter  

Here my latest Roadbike Cycling clip.

What I'm going to improve in the future is

  • add more variations at the last scene
  • usage of ND filters

The shutter speed is too low. The sun was high and even at lowest ISO the quadrocopter reduced the shutter speed which resulted in jerky vide. Not that bad I hope but let me know, please.


引用
トピックタグ
Pierre
(@pierre)
Eminent Member
結合: 4年前
投稿: 24
 
Posted by: @cincity

The shutter speed is too low. The sun was high and even at lowest ISO the quadrocopter reduced the shutter speed which resulted in jerky vide.

Curious, a shorter shutter speed, on the contrary, should favor a more precise image with less lag. However, yes, there is an impression of jerkyness in the aerial tracking of the cyclists and the scrolling of the vegetation in the foreground.

I have the impression that this is a problem of the camera's frame rate which cannot register the high information load at the chosen frame rate given the quantity of new details that each frame contains and according to the chosen quality level.

Yes the defect is apparent, but most viewers probably won't pay too much attention to it.

Otherwise, the editing is very good.


cincity 件のいいね!
返信引用
cincity
(@cincity)
Eminent Member
結合: 2年前
投稿: 45
Topic starter  

I appreciate your reply very much

Though I probably used the wrong terms (and cannot edit the topic anymore) it seems you absolutely have understood what I meant.

I need to make the shutter time longer in the future. Therefore I'm awaiting the ordered ND filters.

At high movement the objects become jerky at crispy short shutter times like 1/250

I'm filming at 30 FPS  and I want to set a fixed shutter speed to 50 or 80.(60 isn't available).

There is a 180° degree rule which explains this matter to record movements at cinemalike framerates of 23,97

 


返信引用
phylsmith2004
(@phylsmith2004)
Reputable Member
結合: 4年前
投稿: 268
 

@cincity

@pierre

Yes the defect is apparent, but most viewers probably won't pay too much attention to it.

That would be people like me -- it is an interesting video just to watch -- and I would not even know there was any defect.  (Just glad it was not a fault of CinGG).


cincity 件のいいね!
返信引用
IgorBeg
(@igorbeg)
Estimable Member
結合: 2年前
投稿: 109
 

I like your "Roadbike Cycling". Unfortunately I have some problems to see the video in your site; maybe it is my problem due to bandwidth. I downloaded your video to local (in my computer). Watching the video there are some jerky points. Do you see that also in your source footage?


cincity 件のいいね!
返信引用
cincity
(@cincity)
Eminent Member
結合: 2年前
投稿: 45
Topic starter  

Do you mean the footage or something Codec related?

I don't see anything jerky except what i said previously about the shutter speed.

At Facebook I saw a huge hang but Facebook re-encoded the uploaded video. But odd though.

 

The video is H264 render output of Cin without any additional re-encoding

The bitrate is 16 mbit

 

Can you check your CPU utilization?

This post was modified 2か月前 6回 by cincity

返信引用
IgorBeg
(@igorbeg)
Estimable Member
結合: 2年前
投稿: 109
 

I am watching your video using VLC on my old Notebook. I can see some hesitation on playback at, around, 0m:30s.
Probably it depends by my slooow cpu. Cpu load from 4% to 20%, it is strange.

May be that are you moving the camera (drone) at a speed greater than shutter speed?


返信引用
cincity
(@cincity)
Eminent Member
結合: 2年前
投稿: 45
Topic starter  

@igorbeg 

I tried to follow what you mean but I'm not sure. Maybe you mean minor frame drops?!

If yes, this is caused by the camera logic of the drone. This is - at the development and price level - a drone I can go wild with but which irregularly makes some minor frame drops.

 

1. Some seconds long drop would be terrible. Facebook made that for my upload. Odd though. Need feedback it anything like that happened. I uploaded it from the Cin H264 Render output

2. Minor irregular frame drops and/or some jelly effects from vibrations - though 3-way mechanical gimbal stabilzation - are within this actual dev to price ratio of the drone - unfortunately.

3. The third thing is the frame to shutter ratio. This can make the image jerky, blurry or cinematic like picture as expected - depending on the movement speed and the used shutter speed.

 

No. 1 would be terrible. So please give me feedback to make the content available to everybody - as it is intended.

No. 2 is as it is. As long I'm using these quadrocopters of this exact type I own and I'm not changing them to a next generation.

No. 3 will just make very quick sideway moving object appear more "as one object". Is the shutter speed too fast, objects of that kind will appear jerky. Because the aperture at the quadrocopter cannot be reduced I need to reduce the amount of light which is allowed to fall into the lens to achieve a proper cinematic effect.

Hope the ND filter will be here by next weekend. The Roadbike Club at  Goettingen is going to make a great event next weekend. We already have spotted some of the best locations.


返信引用
IgorBeg
(@igorbeg)
Estimable Member
結合: 2年前
投稿: 109
 

@cincity
I think that videos by your drone are very good, so what I am saying it's only to understand better if it depends from source video (footage) or by editing in Cinelerra-GG + FFMPEG.

1. I imported your "rennrad-2022hildesheim-rtf.mp4" video in Cinelerra-GG
2. RMB (Right Mouse Button) on the thumbnail (Vicon) of the video in Resource window and Match...->Match_all, so the Project Format parameters are like the loaded video.
3. Insert the video in the timeline using Drag and Drop.
4. In the timeline move the pointer to the 00m30s00f.
5. Using "Numpad_1" (Frame forward) to go forward frame by frame: at 30s:25f I see a drop frame.

May be that what I see in the playback on VLC?
If you load your source video (the original footage) in Cinelerra-GG, is there the same frame drop, in the same position?

 


返信引用
cincity
(@cincity)
Eminent Member
結合: 2年前
投稿: 45
Topic starter  

@igorbeg 

I can see that too.

If you ask me this has to do with the drone source footage.

It appears from time to time.

It is at previous clips too e.g. the clip with the commuter bike pedals at the first scene already.

This post was modified 2か月前 2回 by cincity

返信引用
IgorBeg
(@igorbeg)
Estimable Member
結合: 2年前
投稿: 109
 

Thanks for the confirm and info, @cincity.


返信引用
cincity
(@cincity)
Eminent Member
結合: 2年前
投稿: 45
Topic starter  

I think this has something to do with the drone camera data processing.


返信引用
共有: