Edges of video are jagged in Motion color key

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Level 3

610 points

Edges of video are jagged in Motion color key

I have a quad-core G5 Mac running 10.5.8 and Final Cut Pro 6.0.6, Motion 3.0.2.

I'm learning Motion, and trying to do color keying.

I take video (with a Mini-DV camera) of people in front of a greenscreen, then capture the video from the camera into Final Cut 6, and then export the clip as a short QuickTime movie.

I then drop the QT movie into Motion, and choose Add Filter > Keying > Primatte RT, but the outlines of the people in front of the greenscreen are jagged. I can key out the greenscreen, but the jagged outlines of the people remain as a ragged green outline or halo, and I can't key that out.

Am I doing something wrong?

Any help appreciated.

Tom

Posted on Mar 5, 2015 8:31 PM

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Answer 1

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Meg The Dog

Level 6

13,561 points

Mar 5, 2015 9:13 PM in response to Tom Baker1

If you are working with SD DV then you are probably getting as good a result as you can expect. The artifacts present in DV compression are acerbated by the keying process.

Look in your effects pane and see if there is a filter like a matte choker that you can apply. It may be able to reduce some of the fringing and stair-stepping along the edges of your key.

MtD

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Answer 2

Tom Baker1 Author

Level 3

610 points

Mar 5, 2015 10:25 PM in response to Meg The Dog

Thanks Meg. I guess Motion 3 isn't really capable of keying SD DV, then. I took the same clip over to a Mac Pro that's running Adobe CS 6, and dropped it into After Effects, brought up its keying controls, and the outlines of the people are as smooth as can be, there. Plus there are a heck of a lot more keying controls in After Effects, and I can get rid of any halos or colored outlines without too much trouble.

Motion 3 is from 2007, and After Effects CS6 is from 2012, and I guess a lot of progress was made in keying in those 5 years.

I also compared the keying controls in Final Cut 6 with those in Adobe Premiere, and it's the same situation: I can't get rid of the green outlines in Final Cut, but I can do it in Premiere CS6.

I really want to keep using Final Cut 6 and Motion 3 on my G5 Mac, because I understand how to use them better, plus I like the round-tripping ability between Final Cut and Motion, and Adobe CS 6 is not something I know how to use very well. Also things like the fact that I can open many projects in Final Cut, but only one project at a time in Premiere CS 6, and things like that. But as much as I love the Apple Suite, I guess there are places like keying where it shows its age.

I suppose I'll have to do my green-screen work in Premiere or After Effects, then, and then carry the result over to Final Cut 6 as a QT movie.

Thanks again for the help,

Tom

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