keying interlaced...

[capitanred]

i have some interlaced footage where i should key out the foreground.

now i did, but it didn't work well. especially around the edges. there was a blue outline, and when the foreground moved,the outline was wiggeling. I did first deinterlace, merge fields, or remove fields with the fildskit node.
now it was told me that i should first key the separate fields, and then deinterlace.
but how can i isolate this fields, and then get them back together?

[alkali]

Any comp app should be able to strip one field and leave you with the other. What are you using?

[capitanred]

I'm using nuke 4.7v5

I know that I can remove lower or upper field an having the half resolution(height). but how do i get them later back together?
or don't i need to do it this way? what would be the workflow for this?

[Gentle Fury]

I've never had a problem comping interlaced footage. As long as your key is done right u won't have a problem. Are you using IBK?

[capitanred]

no, i used primatte. but i don't think tat this s the point.
when i zoom into my image, i can see a dark boarder arround the person. it's nearly black.
and this is happening in any case of deinterlaced, interlaced, removed or merged fields...
so i think it is the bluescreen or the camera that are to bad for a goog key

i'll see if i can improve them first