Hi, is this possible to do in combustion?

#1

Hi, i’m using combustion3. I have shot filmed outside. there is a character in that shot. The camera zooms in the character.
What i wanted to do, was to select(make a selection or mask or whatever that is called) around that character, tracker it’s motion(as the camera zooms in) and then make a copy of the selected character(the selection should scale and adaptate as the camera zooms in acordingly). Then i would put fire on the entire background(using combustion particles), and then put the selected character film IN front of the flames, to give the idea he is in front of the flames as the camera zooms in. Is this possible to do without bluescreen? i really wanted to avoid bluescreen because i wanted to film in several live action locations.

please tell me if it’s possible, and if it is, how u think i can do it.

cheers.

#2

If you have a lot of time, and a lot of patience, anything can be done without using a blue screen. It’s just a matter of drawing a poly mask around your subject, and then either hoping you get lucky with the tracking (I think it’d be extremely hard to track against a moving person, without them having placed any sort of tracking points on themselves or anything), or manually keying the mask frame-by-frame.
It depends on the shot, though. In some cases (depending on what quality you’re going for), you might be able to get away with just clever use of layers and layering modes. It really depends on how the lighting and colors of your character varies from the rest of the shot, though.

#3

The person in the shot isnt moving at all(from the same place), its more the camera moving in into a close up of the character. i made a poly selection and i was semi-able to get the result i wanted, but, i wonder why my poly selection doesnt allow Scale and Rotation in the “TRACK” stuff(EDIT: i was now able to enable this, but still the mask wont update its form&size to the animation). this way the mask doesnt update manualy :frowning:
any suggestions?(i’m using paiting operator to do the mask)

#4

Tracking with scale set requires you to track two points; make sure you position and have both of them analyze forward; you won’t see any scaling until you do. (also make sure that you have the right thing selected when you do the tracking; sometimes it’s hard to tell for sure in combustion that you do) Also…Combustion has a nasty little habit of hiding the object you’re applying the tracking to by default when you first setup the tracking points. Make sure you turn the visibility back on yourself.

#5

the success of the tracker also depends on what you are telling it to track. if there is no distinct feature to track and/or enough contrast, no tracker will be able to do it. (this is no fault of combustion or any tracker for that matter, but the ‘fault’ of the person who shot the footage)

//gD

#6

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