Im new to the forum and fairly new to after effects. I have a kinda tricky question. How would I go about having someone set on fire? I have a green screened video of a person running around as if he was caught on fire. How would I attach the fire elements from action essentials 2 to my actor running around so that the fire is constantly following the actor on his back?
From the incomparable Dave LaRonde
Dave's Stock Answer #2:
There is a reason special effect houses charge hundreds of thousands of dollars. Making realistic special effects takes a lot of time, work and experience.
To get you started, try out some of the tutorials on the COW about motion tracking.
Realize that without the light from the fire on the actor or the fire moving in relation to how the person is moving (wind, etc.) it doesn't matter how good your track is, it's going to look fake.
You can compensate for the light on the person with an adjustment layer between the fire layer and the person. This layer should brighten the person and add a bit of orange color. Use a mask to shape the glow to just the part you want. You could then use the same tracking information you get for the fire to keep that glow right there, or simply parent it to the fire (or the fire's null).
As for the air moving the flames as your actor runs around, this might not be too noticeable, but you can always use AE's distortion filters (or maybe the puppet tool) to reshape the flames.
If your actor turns around or has limbs flailing - as is to be expected from someone set aflame - be prepared to enjoy rotoscoping.
Hope that helps.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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