Pull Matte On A Shot With And Without Character

[user_deleted]

Hi
I would like to pull a matte in Shake, of a character over a background. I have the original background WITHOUT the character and the scene shot WITH the character.
I used a ISubA and other tricks (see image)

But is there another better way?
Or does Keylight or Primatte support this feature?
thx

Valerio

[user_deleted]

the idea is right, problem is that if the image is noisy you need to do a lot of filtering to get rid of artifacts (which is not good).

some things i would try:
- average several frames of the clean plate to reduce noise
- make a clean hard matte and a noisy soft matte. expand the hard matte by a few pixels and do an inside with the soft matte , shrink the hard matte a few pixels and max it with the result. this should give you a solid matte with not too harsh edges.
- try a median filter to reduce the noise.

others will probably have better ideas here
but it's a start.
++ c.