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How to avoid loss of quality in slow motion videos? (See examples)

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Steve here again, I'm still very new to videopad, and relatively new to video editing in general?

 

Is there an inherent loss in quality, when a clip is slowed down?

 

For example, see these clips (about 30 seconds each)--

 

Full speed:

2/3 speed:

 

I used Videopad to cut these clips out of the raw footage, and to slow down the one clip to 2/3 speed.

 

Both on vimeo, and in the actual clips (as seen on VLC video player), the 2/3 speed clip is blurrier than the full-speed clip. In particular, if you randomly hit freeze-frame as you play back the 2/3 speed clip, you'll often land on a frame where some of the features are rather blurry, or where there is a fainter "ghost" second image offset from the main image. This is particularly obvious if you look at the long white straps that extend forward in the frame. On the full-speed version, no matter where you freeze the playback, the picture is usually sharper, and never contains a second "ghost" image.

 

Does anyone have suggestions to avoid this loss of quality?

 

The original footage was from a Go-Pro camera, 1280x960 pixels, 29.97 fps. Those are also the settings I entered into Videopad, both for the full-speed version and for the 2/3 speed version.

 

I'd appreciate any suggestions. Hoping to get better results with slow-motion video, was one of the reasons I abandoned the editing software I was using previously.

 

Steve

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Not sure why the clips are not showing up--

 

Full speed clip is vimeo dot com /150807459

2/3 speed clip is vimeo dot com /150807458

 

thanks

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PS I don't care if the slow-motion footage looks a bit "jerky", just want to avoid blurriness and the "ghosted" double images.

 

Steve

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Hi Steve,

 

When a clip is slowed down. There are missing frames in between the original frames. For example slowing down a 30fps clip by 50% (15fps) and export to another 30fps clip, you'll have a missing frame in between every original frames.

 

Currently VideoPad generates the missing frames by cross-fading the original frames. That's why you see the "ghost" image in some frames.

 

We are aware of the problem and knew the corss-fading might good for some videos but not for the others. We are working on providing other options to generates missing frames.

 

Best Regards,

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Hi

 

I think a lot depends on the original speed of movement in the frame. Fast subjects or using big speed reductions will result in bigger movements between the missing frames and so the action will appear jerky and the crossfade in these cases will not help things either. See the references to still ghost images between normal clip-clip crossfades. It's a bit of a catch 22 situation as often its the fast motion clips that you might want to slow down. With slower subjects with smooth motion (particularly if panned) e.g. sailing dinghys, VP gives excellent results.

 

Nat

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Thanks for the notes. I have noticed that video from a helmet cam inevitably has a lot of high-speed "panning" and that's when the problem is most pronounced-- cams mounted rigidly to the vehicle give better results-- all makes sense with replies above, thanks much for the replies.

 

A question-- what If I simply slow down the frame rate I select for the final video? If the original is 29.97 and I slow it by 50% and also select a 50% slower frame rate, would that eliminate the "ghosting"/ cross-fade issue? I don't mind if the video looks slightly "jerky" as a result. I just want the frames to be as sharp as possible

 

If this is likely to help, should I specify my desired frame rate a "fixed" frame rate or as a "maximum" frame rate?

 

Thanks

 

Steve

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