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Holdesta
12-01-2010, 07:06 PM
Update on the kids science video: Have a new Sony PMW EX3 HD camera, Magix Editor 15 and of course LW

Hello all again...been away making stuff and the animations are coming along really well. But now I am getting to the process of the live fiming and putting the two together. Ok so questions in no particular order:

I'm not even certain I understand how this all works trying to learn all this on my own is a ...bit of a challenge to say the least

1 In order to be able to insert a 3d LW object into my 2d footage I will need a 3rd party program to do the tracking? Yes or No

2 In the case of yes which program is recommended (syntheyes, Voodoo etc)

3 In the case of no how does one go about manually tracking in LW?

4 if someone would be so kind as to clarify this scenario I would love you forever. As I understand it

Scenario: Robot verses Human

Robot is created in LW modeler

Human is filmed with camera reacting to "robot"

Footage is loaded into 3rd party tracking softwear (sythneyes ?) which translates the 2d information into a ground plane that 3d objects can interact with?

Footage is then exported to LW Layout

Robot is exported to LW Layout

Robot is animated into the 2d footage.......how? if there is say a tree in the footage can he go behind the tree? or is the 3d information not that detailed?


Thanks so much guys...this is really what I want to be able to do...special FX and creatures in live footage :)

nickdigital
12-01-2010, 08:53 PM
1. Yes, generating a track with a 3rd party program is best. LW doesn't have a motion tracker natively aside from someone doing it by hand which is incredibly tedious. You would need to match the camera zoom and motion which 3rd party programs are able to extrapolate pretty well.

2. Syntheyes is good. I'm not aware of any good ones. I've heard of one called Icarus. I'm not sure if it's still available or how up to date it is.

3. Load in live action footage as a bg image sequence and animate the camera. You could build proxy objects to use as markers for your 2d footage. This is where having the real wold data helps (how tall someone is, the lens on the camera, how far apart specific items were from each other, etc). Going the 3rd party program route would probably be easier IMHO.

Once you have a camera track exported from the 3rd party program you'll have a LWS file where you could put your robot in. The LW camera will behave like your live action camera so this again is where knowing where your live action stuff is is important.

To get your robot to walk behind a tree you would need to do some rotoscoping in comp package like AfterEffects. You could do it in LW by building that tree and use it as a hold out matte but doing it in comp is better.

nickdigital
12-02-2010, 02:24 PM
This thread might be helpful too.
http://newtek.com/forums/showthread.php?t=94121&highlight=motion+tracking

Holdesta
12-07-2010, 08:49 PM
Thanks so much NickD you always look out for me. PS my dad says thanks too :)

nickdigital
12-07-2010, 09:54 PM
Thanks so much NickD you always look out for me. PS my dad says thanks too :)

LOL
Well say "Hi." to your Dad for me then.