Shake background

[tom k]

how would i shake the background. I want my subject to remain unchanged but just have the background look like there was an earth quake

 

[Spartacus]

I used a plugin in Combustion for that a couple of years ago, called earthquake or tremor (not sure...)
I suppose your BG also is on a separate plate?

 

[tom k]

so i would have to shoot the background on a tripod, then add in the actors to that shot and then take just my background timeline and shake it...i am confused

 

[FiddlerMD]

that sounds fairly simple - or you can chromakey the actors onto the shaking background

 

[Spartacus]

so i would have to shoot the background on a tripod, then add in the actors to that shot and then take just my background timeline and shake it...i am confused

Well, there is this other option where you´d need a hoovercraft and a H-Bomb...
if you want to treat FG and BG differently you have two options: rotoscoping and keying.
Keying should do the job in your situation, search here or on the web there´s a lot of info on this...

 

[tom k]

ok let me check it out

 

[tom k]

sweet man i got it/. I chroma keyed one layer then shook the other freaking cool. i have to check more into the rotoscoping looks cool though.

 

[oneinfiniteloop]

Rotoscoping is the pain in the @ss version of keying.