Why are 25/30p videos vibrating on all my playback devices?

[Bencuri]

When I watch a progressive 25/30p FullHD video on my HDTV or any of my 3 laptops, the videos are always vibrating when something is moving on the video, or when there is panning. 60/50 "p" and "i" videos doesn't do this, only the 25/30p videos. These videos are also vibrating during recording and when you play back on the camcorder. I have 3 different camcorders that can record in Full HD 25/30p, it happens with all. One is a Samsung HMX-S10. I also had a Canon HF M406, the 25p video that it recorded does the same, and did the same as well during recording.

I get the same effect when I convert a 60/50p video to 30/25p.

I thought this is a general thing, until we tested the new HDTV of my friend. On that TV the 25/30p videos play very fine and smoothly. What causes this? What is different on that TV?

My TV is a: Philips 32PFL5604H/12

My friend's TV is a: Samsung UE40EH6030

[jagabo]

That's the nature of low frame rates like 25p. Watch the video linked to in this post:

https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30-...=1#post1888926

Watch it full screen. Your friends TV was probably using motion interpolation to generate in-between frames for smoother motion.

[Bencuri]

That's the nature of low frame rates like 25p. Watch the video linked to in this post:

https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30-...=1#post1888926

Watch it full screen. Your friends TV was probably using motion interpolation to generate in-between frames for smoother motion.

So if my HDTV does not support 60/50p playback, it is better to convert videos to 50/60i, right? If yes, what converters can do that? All the video converters I found support only p as saving format. Is there a good converter that can do that job well?

I am stunned anyway that 24p recording is so ppopular, despite the vibrations.

The linked file is just vibrating like my TV. It is exactly the same effect that I see here at home.

[_Al_]

24p, 25p, 30p you have to record in manual mode, with longer shutter speed, 24p (1/24,1/48), 25p (1/25, 1/50), 30p (1/30, 1/60). You cannot use auto modes, camcorders will use very short shutter speed (1/100 or much shorter if you record during sunny day) and your video will be "strobe effect" like.
On that sunny day, or just during daylight mostly, you have to use neutral density filter to get right exposure with long shutter speed, so it is no point and shoot business and still you cannot pan with camcorder as you'd like, any hand shake or jerk will introduce blurriness in video ...

[jagabo]

Long exposures (motion blur), DOF blur, and low contrast help. But 24p to 30p fps is always jerky and flickery. If you have 60p and a device that can't play it convert to 30i. Leave 30i as 30i, and 25i as 25i.

[Bencuri]

Long exposures (motion blur), DOF blur, and low contrast help. But 24p to 30p fps is always jerky and flickery. If you have 60p and a device that can't play it convert to 30i. Leave 30i as 30i, and 25i as 25i.

You mean real 30i as 15 full frames halved, or you refer to 60i? Some of you was describing these 'i' namings, but I am still uncertain about these definitions.

[jagabo]

60i is just another name for 30i. Invented by a marketing droid. 30 frames per second with two fields in each frame, intended to be viewed separately and sequentially at 60 fields per second.

[Bencuri]

Well, finally I see what you mean.

By the way, if there was a media player that can do that interpolation what my friend's TV does, that would even be a better solution to save time. That interpolated video looked really great, and then I just need to load the files to the player and can project it on my TV right away. Does any media player with that feature exist? I mean those small player boxes, like WD TV Live, etc...

[jagabo]

I don't know of any standalone media player that has motion interpolation. There are a few software players under Windows that have it. For example: http://www.svp-team.com/

[Bencuri]

If you have this scene, can it be made non flickery, or it is above the tolerated contrast level in 30p? I mean the butterly on these videos:

link

The settings are:

1.file: 400 ISO, 1/60, 2.0 aperture
2.: 400 ISO, 1/30, 2.0 aperture
3.: 400 ISO, 1/30, 2.4 aperture

I can set Aperture, Shutter and ISO on my camcorder, I don't have that separate EV setting.

[jagabo]

I think SANY4012.MP4 is about as smooth as you will ever get a shot like that at 30p. Here it is motion interpolated to 60p (video only, h.264, mkv).

[_Al_]

.... and still you cannot pan with camcorder as you'd like...

1.file: 400 ISO, 1/60, 2.0 aperture
2.: 400 ISO, 1/30, 2.0 aperture
3.: 400 ISO, 1/30, 2.4 aperture

You cannot produce something better with 30p, those settings with 1/30 or bit worse 1/60 will help it as oppose settings with much shorter shutter speeds but no pans like that. This is what you are going to get ...

[jagabo]

That's why TV runs at 50 or 60 fields/frames per second. Movies (24p) are always jerky. Just pretend you are a film aficionado and love that jerkiness for the sense of surrealism it creates!

[Bencuri]

I am just stunned that I asked many people who use 24 or 25p whether the vibration disturb them or not. They always comment they cannot see vibration on their videos. I have just contacted a guy like that, I sent him this test about those running black rings in 24/30/60p. He says he can see the vibration on that test, but apart from that he doesn't see them on his own videos or his preferred videos from others. This is quite annoying. I would like to sit in front of their computer now and check what they see exactly.

[jagabo]

He says he can see the vibration on that test, but apart from that he doesn't see them on his own videos or his preferred videos from others.

He just never noticed before because nobody pointed it out. Once you start seeing this type of flicker/jerkiness you start to notice it all the time.

See the video in this post (a shot from 2001 A Space Odyssey):
https://forum.videohelp.com/threads/305001-Current-HD-standard-is-a-FAIL?p=1872228&view...=1#post1872228

And the same shot motion interpolated to 60 fps (downscaled):
https://forum.videohelp.com/threads/305001-Current-HD-standard-is-a-FAIL?p=1872955&view...=1#post1872955

[_Al_]

30p - you follow moving object, as much as you can. Simply do not pan as much as you can, keep an object in the frame, watch what you do with camcorder, or slowly without any zoom, cut panning out while editing.
Get a wide angle - a must if camcorder doesn't have at least 30mm. It is part of this whole problem a bit too, you have everything on wide, and you need detail you get closer. Not panning and zooming the scene ...

[Bencuri]

First I didn't notice the vibrating when I watched the 30p version (I started with that), but setting the playback to loop I noticed them in the background. First I was concentration on the man walking, and that took my attention away. But indeed the charis and other things are vibrating.

I just don't understand then that if you have to take care about panning, how did they record travel documentaries in the 70's for example? There you cannot always plan every moment. Yet there are several panning scenes in such documentaries? Or they considered that when the movie will be watched on TV, there is interlacing?


P.S: I would be so glad if my camcorder videos would play as smooth on my computer as this one. It is a very good conversion.

[_Al_]

documentaries do not have such a fast pans, things are not so close to camera, you pan eventualy, why not, not that fast, keeping distance or whatever is in relative movement should be out of focus, film cameras have shallow debt of field, 35mm frame or 16mm, you do that easier, our camcorders focus everything , sensors 1/4" almost everything, 1/2" is much better ...

[Bencuri]

documentaries do not have such a fast pans, things are not so close to camera, you pan eventualy, why not, not that fast, keeping distance or whatever is in relative movement should be out of focus, film cameras have shallow debt of field, 35mm frame or 16mm, you do that easier, our camcorders focus everything , sensors 1/4" almost everything, 1/2" is much better ...

So you mean that in case I change the focus type, that can also help to make motions more smooth in 30p? You know in that menu where you can select whether the camcorder should separate the image to a particular amount of fields and observe those, or use point focus, etc.

[jagabo]

I just don't understand then that if you have to take care about panning, how did they record travel documentaries in the 70's for example? There you cannot always plan every moment. Yet there are several panning scenes in such documentaries? Or they considered that when the movie will be watched on TV, there is interlacing?

3:2 pulldown when film is telecined to TV makes the problem worse, not better. In addition to the inherent jerkiness of 24 fps film you get 3:2 judder.

All 24 fps film (99.99 percent of movies) has this problem. Film makers understand it an minimize it as best they can with the techniques that have been described.

[_Al_]

So you mean that in case I change the focus type, that can also help to make motions more smooth in 30p? You know in that menu where you can select whether the camcorder should separate the image to a particular amount of fields and observe those, or use point focus, etc.

Your sensor and optics in consumer your camera is a given, you cannot change depth of field much (you might work with focal length - zoom - to get shallower depth of field but you loose space somehow, it looks flat), that what you are talking is to fix focus, but in a sense it still has the same depth of field, you just fix it somehow in the menu to some distance or object. But it is huge in the first place.

The clip you did, even 35 mm camera cannot make it look somehow all right, it is a fast pan , close to object, not enough frames per second for that, it will introduce strobe effect even with long shutter speed. There is nowhere to focus even with shallow depth of field, everything is a mess.

[Bencuri]

In the thread where the Odyssey videos were linked, so here, that guy brought up the idea that due to the sharper nature HD, the vibrations comes alive unlike in the old, lower resolution of PAL or NTSC. So if I select SD shooting mode on the camcorder, that could also help a lot to minimaze the vibration, or that guy was not right? Actually there are several occasions when I record a video when the emphasis is not on the resolution but just to document something, and a smaller window for playback is enough. Like for a Youtube video. In that case Sd would do. Many people doesn't even have enough bandwidth to play Youtube videos in HD. So in these cases selecting SD mode can help further?

[jagabo]

So if I select SD shooting mode on the camcorder, that could also help a lot to minimaze the vibration, or that guy was not right?

Not really. Only a tiny bit. You could get the same thing by defocusing the HD shot.

[_Al_]

SD NTSC or PAL records 60 or 50 "half" frames per second, temporal resolution is fine here, it is interlaced, everything is smooth.

Posting this footage on internet you have to go in some point through deinterlace to 30 or 25p and you are at the beginning of the problem, even much worse, either some blend deinterlace makes this smoother but blurred, blended, or you get strobe effect anyway to keep everything sharp (possibly throwing one field away) and showing footage with even shorter shutter speed than if you shoot 30p right away.

This goes hand in hand with alowing Youtube 50p or 60p (even same bitrate , wouldn't make much a big difference mind you - this is another topic) , they should allow higher fps, from business point I guess why would they bother, of course. Not only because interlace footage but there are 50p/60p camcorders at large nowadays. For yourself, setting up jwplayer and similar you can post 50p/60p .

[Bencuri]

Damn, when I purchased the Canon camcorder that is 25p/50i, in the advertisement the cinema style shoot seemed so easy, you just switch the button to cinema mode, and it seemed all done. Who would wonder after this that such problems may arise

When I first noticed these vibrations, I made the that video with my Sanyo HD1000 camcorder, I thought the camcorder is faulty, because of the strobing. I almost sold it to get rid of the faulty camcorder...