View Full Version : How did they do this?


Scott Nelson
November 6th, 2009, 09:14 PM
Ok, So, My first though was After effects, but then again I am sure I could pull this off in Premiere.

So, That's why I am in HD Editing solutions cause I don't know where I should put this.

Please take a look at this video. I have been asked to make a effect similar to the "Stopping in mid air" effect on this video.

YouTube - Knife Show Volume 1 (http://www.youtube.com/watch?v=tlT5pUXiW7E)

My first though was that they just exported the frame, sent it to PS, made the background transparent and then motion tracked it back in. Is there an easier way to do this effect?

Also, There is a part in it where the guy is flying through the air and the back ground is replaced with black video and a name/logo. Would I be correct in thinking this is just a garbage matte around him?

Thank you!

Shaun Roemich
November 6th, 2009, 11:19 PM
My first though was that they just exported the frame, sent it to PS, made the background transparent and then motion tracked it back in.

Pretty much, yup.

Easier? That's probably the easiest way to do it, but I'm far more proficient in PS than AE...

Giroud Francois
November 7th, 2009, 07:04 AM
Mokey allows to track an object on screen and extract him from the background.
then you can have object alone, background alone, and masks.

Tripp Woelfel
November 7th, 2009, 09:05 AM
I think you're right on both counts. You could do the motion tracking in PP or use Dynamic Link to AE. I think PP would be simpler because there's not much to the motion.

Scott Nelson
November 7th, 2009, 07:13 PM
well, I figure if I did it I would set it up on a tripod and just film it wide, then go in and record on a new camera in AE zoomed in a little and add some motion.

Well, Thanks for you hlep! I figured that that was about it but was just making sure of it..

Shaun Roemich
November 7th, 2009, 07:43 PM
But then how would you create the matte?

Since the action stops in the clip, it's just a cutout, which is then animated. No need for motion tracking because the still is larger than the image it is cut from so as long as the cutout covers the original, the effect is "believable".

Scott Nelson
November 8th, 2009, 10:26 AM
Ok, I just got lost there... Elaborate alittle for me.

Daniel Bates
November 8th, 2009, 12:26 PM
The still image doesn't need to be tracked because it is scaled large enough to cover the original image in the background plate.

Shaun Roemich
November 8th, 2009, 03:29 PM
Thanks Daniel - yes, that was my point. Motion tracking would be used to PRECISELY follow another motion path. What you are talking about is simply a motion path, which is FAR less difficult and requires far less processing power.

Tripp Woelfel
November 8th, 2009, 08:17 PM
Shaun's correct. The background doesn't need to be tracked. I used incorrect nomenclature. PP doesn't have motion tracking. Just motion.

My bad.

Shaun Roemich
November 8th, 2009, 11:55 PM
then go in and record on a new camera in AE zoomed in a little and add some motion.

To further elaborate, this would create a "zoomed in" version of the person centred on but would still have the background. You would still need to create a matte to separate the foreground (ie. PERSON) from the background plate (ie. the entire video that the person was cut from)

Dean Sensui
November 9th, 2009, 12:37 AM
I was gonna say that they way they do this is practice, practice, practice! :-)

Looks like a mix of rotoscoping and mattes.

Shaun Roemich
November 10th, 2009, 09:16 PM
Ok, so here's where I admit I only watched the first 20 seconds or so.

The stuff that follows (the jump off the snow ramp) certainly DOES include motion tracking and mattes and stills.

I was going by the very first "cut out" over the pool.

I apologize for the inconvenience and any confusion I may have caused.