twin compositing

TeeJay wrote on 10/18/2004, 6:04 AM
O.K, everyone has probably seen a show where an actor plays the part of his/her own twin and appear in the same scene interacting.

Now, obviously the scene is shot twice, but how are both images composited together to look seamless. Is Vegas capable of doing this type of editing?

I'd love to hear if anyone has done this with any degree of success.

Cheers,

TeeJay

Comments

PigsDad wrote on 10/18/2004, 6:12 AM
The easiest way to do this is to keep the "virtual" actor each on their own side of the frame, and shoot it twice (with a tripod and the camera in the same position, of course). Then in vegas, simply use pan and crop (or track motion - not sure which would work better) to use the correct half of the frame from each event, and put them together.

I believe I saw a really good example of this on Cheinworks site -- it was a short video of a guy's daughter who had a "hidden" twin (really cute).

Now, if you want the two actors to cross each other, or interact, that is a whole different ball game.

Edit: Just found the link for the example:

http://www.vegasusers.com/vidshare/textdisp?paulholmes-kaitlinstwin

It is now archived, but sometimes you can contact the site to get access to it.
apit34356 wrote on 10/18/2004, 6:33 AM
One of the easiest ways is to shoot the "double" against a green backdrop, then merge together the different footage. you will need to have a layout, markers, positions for the actors know where to move in the scene, this is usually the most differcult part of the shoot. merging the footage in vegas is simple compare to the laying out the scene.
[r]Evolution wrote on 10/18/2004, 12:27 PM
PigsDad has the easiest way.

Set up your camera & Tripod exactly where you want it. (Do NOT move the Cam/Tripod!)

Shoot your talent facing one way doing his lines. You can have a 'stand in' on the other side delivering lines. (Do NOT move the Cam/Tripod!)

Reverse the two. Now have your talent & stand in switch sides & script lines. (Do NOT move the Cam/Tripod!)

In post apply a Cookie Cutter to both clips cutting out the side with the Stand In.

Wholla! You now have the same person talking and interacting with himself without having to fuss with a green screen or chroma keying. This technique is quick, easy, and will yield the most realistic look. Try to get a Stand In that is as close to the talents height as possible. This way the Eye Line will look realistic and they will actually look like they are talking when you composite the two.
Former user wrote on 10/18/2004, 12:48 PM
Also, be aware of shadows. IF the light changes or shadows are cast, these can cause for matching problems.

Dave T2
blacksheep699 wrote on 10/18/2004, 3:16 PM
well..there is another way besides green screens and shooting the scene will splitting it in half down the middle....if you watch the Greenday music video American Idiot..you will notice that one guy moves mega fast..one normal and one reallly slow...the way you could composite that together is either matching the camera movement for each of them...then stack them all together on top of each other..and on the certain parts where the characters cross each other...use the Beizer tool and cut around the shapes frame by frame...its the most labor process but it brings out really good results if you act out and time everything together properly.
Hope this helped you out a little bit.

blacksheep


TeeJay wrote on 10/18/2004, 6:15 PM
Thanks to everyone for your ideas, I'll be sure to try some of them out.

Actually, Blacksheep699, your post reminds me of an old Paul McCartney video clip for his song "coming up" (early 80s perhaps), which was set in a studio and he plays the part of about 10 different band members. I actually had a bit of a play at doing a similar version with myself playing drums, guitar and vocals, using the pan crop tool, but I just couldn't make the overlaps believable. I'll experiment with keyframing some masks.

Cheers,

TeeJay
johnmeyer wrote on 10/18/2004, 9:21 PM
If you want to do something even more complicated, including having actors switch positions during the scene, check out this tutorial from one of the Vegas developers. While it is a simple clip, the results are pretty amazing.

Cat Demo

In this demo clip, there appear to be two cats (actually a third cat just sits at the edge of the frame doing nothing). The two siamese cats are actually the same cat. During the clip, one cat leaps in front of the other, goes to the top of the couch, and then walks behind the other cat.

The tutorial at the site above is excellent, and if you can understand what is going on, you will "go to the next level" with Vegas.