VSE question - Rendering frames to an animation with varying FPS

So I have an animation that I have made between two files - The first is of a piece of paper being blown out of a window from inside of a house, the second is the paper blowing through the air outside of the house (The scene would have been way too poly heavy to do in one file) 

The animation is seamless so the switch works at the point when the camera goes through the window glass. 

The problem I have is that the way I have made the paper blow with the camera following it is quite complex , with various constraints and any slight change to anything messes up the whole shot. 

Now both shots need to be made into one animation in the VSE. The issue is that shot one looks fine at 24FPS , whereas shot 2 really needs to run at 16FPS or it looks odd. Usually I would just extend the keyframes of shot 2 to suit but as mentioned earlier , it messes up hours of work and I would be better starting again.... 

Is there a way to have the VSE (or any other way) make this animation with the first section at one frame rate and the second at another?

I suppose I could just make them as seperate animations and join them together in the VSE but I am not sure how that would affect quality? 

Thanks in advance. 

  • Matthew Fricker(frikkr) replied

    EDIT* 

    I tried rendering out each shot at its respective frame rate into movie files , and then importing those movie files into a new VSE file and rendering them out into one movie - but as you still have to set a frame rate  even when using pre-made movies , it just gives you the same result.....

  • spikeyxxx replied

    Hi Matthew, I am not sure if this will work and don't have time to test it, but this sounds like a job for the lesser known 'Time Remapping' feature to me:

    Render the 16FPS part out as a video at 24FPS with the time remapping as above and then 16 frames of the original should last 24 frames in the newly created video, so you should (theoretically, if I didn't make any mistakes) be able to combine that with the 24FPS part.

    Again, I didn't test it and I do not guarantee success, but it might work...(I hope it does!)

  • Matthew Fricker(frikkr) replied

    Ok brilliant , I will have a play about with that and see if it works. I've never heard of that feature before. Maybe @waylow has used it before? 

    Thanks again spikeyxxx!

  • Wayne Dixon replied

    Yeah I have never used the time remapping.

    But I don't think any video player will be able to handle a variable frame rate as part of the same video.  So to combine them, you will need them to run at the correct animation speed for the video output.

    What does that mean?

    Even though you want it to look like 16fps, you actually need it to be 24fps (if the is the final output frame rate you want)


    I would actually try the NLA for this type of thing because it will sample the animation data rather than just changing the speed of the video playback.  I think you want to have the animation running at 24fps but the speed is at "16fps" if you know what I mean. eek - now my brain hurts.


    Time mapping might do the same thing - but I have no idea how it works.


    Also check out this video by Looch.

    https://www.youtube.com/watch?v=Nce7SVJD330

    This might also be an option, to have finer control over things. (you can always render the image plane.



  • Matthew Fricker(frikkr) replied

    Thanks @Waylow , appreciate the input. I will have a play around now that I have gathered advice and got a better understanding of it all.