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View Full Version : Dropped frames in animation from LW -> Premiere



bobakabob
10-23-2012, 02:19 PM
I've rendered an animation scene from LW 11 to single TIF frames at 30 frames per second. The scene appears to play smoothly in LW Preview.

However My Premiere film project is set to 25 fps (I have to stick to this frame rate). After importing the still images as a sequence into Premiere Pro 5 the rendered sequence looks subtley jittery and on close inspection appears to be dropping a frame every 5 frames or so.

Am I doing something stupid? As the 30 fps sequence took an eternity to render I can't afford to change the LW setting to 25 fps and start over. I can understand why 30 -> 25 fps video conversion might be a problem but find it baffling why a still image sequence should even be affected in this way.

Any enlightenment or workaround would be greatly appreciated :)

nickdigital
10-23-2012, 02:22 PM
Well your changing the fps...you're going from using 30 frames a second to 25. What should happen to the unused frames (30-25=5)?

As for a workaround you might be stuck. You could try to edit your animation by stripping out the frames you don't need but you'll be changing the flow and timing of what you did.

bobakabob
10-23-2012, 02:38 PM
So Premiere is compressing the 30 fps sequence to 25 and 5 frames are dropped as a result. It doesn't 'carry over' these frames? Sorry if this seems so blindingly obvious, maths was never my strongest subject.

If I was to go back to the original LW scene and changed the frame rate from 30 to 25fps and rendered the scene again (I'd rather not) would that resolve the issue or create still more problems? Is there a workaround?

UnCommonGrafx
10-23-2012, 02:50 PM
If 25fps is your normal, you should change that in LW.

There are supposed to be conversion possibilities...

https://www.google.com/search?q=frame+rate+conversion+30fps+to+25+fps&rlz=1C1DVCI_enUS371US371&aq=1&oq=frame+rate+conversion+25&sugexp=chrome,mod=0&sourceid=chrome&ie=UTF-8

nickdigital
10-23-2012, 02:59 PM
So Premiere is compressing the 30 fps sequence to 25 and 5 frames are dropped as a result. It doesn't 'carry over' these frames? Sorry if this seems so blindingly obvious, maths was never my strongest subject.


Well if it carried the frames over then it'd be shifting all your animation down. For example, at 30fps you had something happen at the 2 second mark (frame 60). At 25 it's putting that same mark at frame 50. If Premiere were to 'carry' the frames over then what you expected to happen at the 2 second mark would be happening later.



If I was to go back to the original LW scene and changed the frame rate from 30 to 25fps and rendered the scene again (I'd rather not) would that resolve the issue or create still more problems? Is there a workaround?
I think it should. The upside is that you'll have less frames to render now.

bobakabob
10-23-2012, 03:14 PM
Thanks for the feedback guys. I guess it's just plain common sense to stick to a single frame rate from start to finish. With my current project unfortunately frame rates are mixed.

Starting from scratch what frame rate would you recommend setting LW & Premiere for eventual screening on Vimeo? On the web there doesn't seem to be a consensus, 25 or 30 fps?

nickdigital
10-23-2012, 03:33 PM
Probably depends on your delivery format. 25 is Pal. 30/29.97 is US tv/video. 24 is film. Your framerate will result in very different viewing experiences. When I worked on Troopers we did all the handheld video stuff at 30 to make it look like handicam stuff. But everything else was 24 to make it feel more cinematic.

2create
10-23-2012, 04:59 PM
Interesting to note that I've tested 24, 25 and 30 on a ram preview player from an image sequence and there's definitely some minor jitter on the 24 and 25 fps. I'm wondering in part if this is to do with the number of hertz most computer monitors run at. Presently every machine we have in our studio is set to run at 59 or 60 hertz, a much nicer multiple for 30fps.

mdharman
10-23-2012, 07:43 PM
In the Premiere bin, check your still sequence. Did it import it at 25 fps or another rate? I run into a problem with still sequences that I want at 24 fps. They always come in at 29.97. I have to right click, modify>interpret footage, and then set the frame rate.

jeric_synergy
10-23-2012, 08:12 PM
Rather than re-rendering in LW, you might try something that converts frame rates better than Premiere, if you can find something that DOES do that.

For instance, I'd give AE a whirl, since I've already purchased it.

But yeah: stick to one frame rate.

bobakabob
10-24-2012, 07:32 AM
Many thanks for all the responses. It looks like the issue of mixed frame rates can be fixed to avoid jitter by changing default frame rates for each sequence in Premiere from 29.9 to 25 as mdharman suggested.

Silkrooster
10-26-2012, 12:02 AM
I wonder if that is the default behavior or is the fps in the metadata of the images somewhere? If it is I can't find it. Another solution is to not check the sequence box and select all files and import as stills. Before import you can then set the frame rate per still in the preferences. But its a work around and not as pretty of a solution.

Edit : this post is in response to mdharman's post.