Help Using Timewarp effect with a Matte
by Scott Bush
on
Jul 4, 2009 at 1:48:16 am
Hi all,
I have a short 15-frame stop motion clip that I would like to slow down and smooth out using optical flow. I know the timewarp effect in After Effects uses this technology, and can make use of a matte layer to help smooth artifacts, but I am having a hard time getting it to work properly, and the AE documentation is a bit sparse as far as this goes.
I figured I could duplicate the stop-motion layer, and draw some masks to roto the foreground elements - to give timewarp something to work with. But when I tell the plugin to look at that layer's alpha, I see no difference in the results - certain items in the frame are getting distorted still as they pass one another.
Do I need to slow down my matte layer as well to match the new duration of the timewarp'd layer? Am I right in using the alpha of the masked layer?
Re: Help Using Timewarp effect with a Matte by Todd Kopriva on Jul 5, 2009 at 1:34:47 pm
Did you precompose the layer with its masks? Often, when an effect seems to be ignoring the masks on an input layer, this is the solution. Precompose, and use the precomposition layer the matte layer.
I'm not in front of After Effects right now. If this doesn't work, I'll see if I can help out when I can play along in After Effects.
BTW, the After Effects documentation is deliberately sparse on a lot of the details in Timewarp, since the folks at the Foundry have already documented it (as Kronos). That's why one of the first paragraphs of the "Timewarp effect" section points to the Kronos documentation. Of course, if this isn't adequate, I'd like to know so that I can fix any deficiencies or defects.
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Todd Kopriva, Adobe Systems Incorporated
putting the 'T' back in 'RTFM' : After Effects Help on the Web ---------------------------------------------------------------------------------------------------------
Re: Help Using Timewarp effect with a Matte by Scott Bush on Jul 5, 2009 at 2:58:05 pm
Thanks for the reply, Todd.
I'm not in front of AE now either but wanted to note that I did follow that link - but because it gave me a FCP Fronos manual, it made no mention of pre-composing to use masks... I will try that though, probably should have thought of it :)
