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Scott212
03-12-2005, 12:07 AM
This seems to be a common result I'm getting from our green screen stage here at school. Why does this look so nasty, is it a spill issue? There is also some nasty aliasing goin on with this footage. I'm not sure where it came from.

Tommi
03-12-2005, 10:00 AM
Maybe this link helps: http://www.pcquest.com/content/multimedia/2004/104070101.asp

There's been a similar post here recently. The artifacts come from the reflected light from the green screen which color the face of the actor. This can be avoided by separate lighting of both the green screen and the actor. Also the distance between screen and actor should be increased. But AE has got some good plugins to get rid of these artifacts

XanderFX
03-22-2005, 12:47 AM
Tha aliasing may have something to do with your field dominace being reversed try switching to odd from even or vice versa or you can ignore fields all together. you can do this by right clicking on the file in the project window and selecting interpret footage>Main and then changing the separate fields option

artisanfx
03-22-2005, 10:14 AM
it seems that you was shooting this video with a dv cam thats the most problem by dv cam shoots there left some shadow arround the edge when you try to key it

there was some site that was explain about this problem with dv cam shoots but i can't remember the url now sorry :(

I got the same problem like you have somethimes before most keyers didn work good enought but there is one you can use and get also good results with it its the primatte keyer
if you use this key you will god a good results what i think will be sold your problem nearly

Luis J.
03-23-2005, 06:56 AM
What keying filter(s) are you using? What version of AE are you using?

artisanfx
03-23-2005, 08:12 AM
I am used after effect 5.5 and for the key primatte keyer 1.5

also see this at http://www.adobe.com/products/plugins/aftereffects/main.html under the primatte


there is also ultimatte http://www.ultimatte.com (http://www.ultimatte.com/) that will give you also nice results

Scott212
03-23-2005, 03:39 PM
Thanks for all of your replys guys! I have found that the problem is a combination of two things. It is one part too much spill from being too close to the wall and not using spill supressent gels on the lights, and part two capturing to mini dv tape (mostly the latter). The 4:1:1 compression scheme used on minidv tapes lacks enough color information to reproduce the reds and blues coming from the object and gets over powered by the green spill. There also is not enough color data captured and you get very chunky edges because of lack of gradation between levels of color. The ring around it is a premultiplying errror on my part and can be adjusted in most keyers such as keylight.

Most excellent tip: Import your footage into Final Cut Pro and run a filter on it called 4:1:1 Color Smoothing. It can be found under Video Filters>Keying>4:1:1 Color Smoothing. It will smooth the chunks out and lots of times it will restore information around the edges of your subject. What a life saver!!

Thanks all,
Scott Willman

morimitsu
09-04-2005, 12:31 AM
¨Most excellent tip: Import your footage into Final Cut Pro and run a filter on it called 4:1:1 Color Smoothing. It can be found under Video Filters>Keying>4:1:1 Color Smoothing. It will smooth the chunks out and lots of times it will restore information around the edges of your subject. What a life saver!¨



Is there a similar filter in Premiere Pro or After Effects?

Thanks in advance.

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